The should have been...

As people now know I am experimenting, (quite successfully I think), with Gauge 3 and this will be the third loco for this that I have built. It was designed by Sir Vincent Raven of the N.E.R. and is a typical looking mid wars period electric loco running on the UK std (of the time) 1,500 Volts DC.

There however the "normality" of the loco ends...

It is a 2-C0-2 design and uses Steam Era design technique to operate. The loco has 6 feet 8 inch driving wheels with what is a perfectly logical high speed spoke design -which is unique to this loco. The loco used a Quill drive and has 6 radial spokes, which then split into 3 and hit the wheel rim at 18 equidistant points, the split giving a central spoke with 2 forks at 45 degree angles. The reason is to produce a non resonant wheel at high revs -something an express loco would need. The short fat spokes made a for a high resonance point -far above what would be encountered in normal running and it made the fitting of the Quill drive to the wheel far easier. This forms a 6 arm "spider" to the spokes from the large gear wheel.

Given the type of locomotives that I normally build the question has arisen -what would terrify me to build? The answer is this loco... It is not actually going to be a hard locomotive to model, it is very slab sided, (although each end does curve in slightly to take account of York platforms -a place it never got to visit).

I fell in love with this loco as a 10 year old from a postage stamp in my collection.

This is a locomotive that really should have been... It had the number 13 and despite this was actually a very nice loco and survived (almost) to preservation -I personally consider it a great loss that this was not done. It was designed for a project that never was realised and thus it was doomed to be a one off. There are several pictures of that I know of -but all of them are either photo grey shots, or of it sat in idle decay in Darlington paint store, I have never found a photo of it actually running under its own power. I do have a photo of it with an EF-1 awaiting the cutting torch, and finally one of it being towed to the cutters torch in Rotherham.

I consider this to be one of the saddest photos that I have in my collection.

Here is my provisional working drawing of the articulation needed for this locomotive. The front and rear bogies will be held in place with two parallel arms and the bogie pivot at their ends. I have chosen the Bissel bogie technique over the Adams bogie, as it means that I can easily remove the bogies for servicing -if and when required. The three driving wheels will pivot in the manner of a Clemens truck thus giving the loco a degree of flexibility that it would not have with a totally rigid wheelbase. Only the two outer driving wheels (axles 3 and 5) will be powered. This simplifies the motor arrangements, each of the powered axles can simply have a transversely mounted motor with a spur gear.

See Picture 1

Well a few weeks have passed since the last entry and I have completed the current loco -so I suppose that it is time to start this one... The first problem that I have run across is (sur prise) the wheels. After several weeks of failed drawings I have arrived at a drawing, which although not correct, is the best possible "wrong" that it is easy to make. I am going to make a simple plate wheel with 6 holes in it to take the "spider" from the "bull gear" and then applique the spokes onto the wheel. This is a definite cheat and I am embarrassed to say that I think this could be the only way that I can do it. The spokes will be cast in resin from a "positive" made from 5mm sq pine, some balsa sheet, and Isopon P38. I have tried two model engineering firms with my wrong drawing and so far I have met with polite (but firm) refusals.

The only option that is on the horizon is for me to buy a Lathe and a Milling Machine and (gulp) try to do it myself....

Although it is not mentioned by name I have come across references to how the locomotive would have operated in the following (facsimile re-print) book "Railway Electric Traction (1922)" by FW Carter. This is quite a fascinating book -but on a personal note I would love to string up the person who did the original copying/scanning of the pages for the facsimile re-print. All of the illustrations are in either black or white i.e. black shapes on a white background... The text is good -but some care could have been taken with the size of the enlargement!!! The relevant chapter (number 3) deals with the types of locomotive and the "British Patent 163185" design. This design is a 2-C0-2 with Quill drives with 2 motors per driving axle, and bogies with front and rear Bissel bogies. The book can be found on-line and down loaded if you like -I bought a copy from Kessinger Publishing. I have my scanned drawing from the NER record Volume 3 -suitably enlarged to "full model size" at 13.5mm to the foot and actually I think I am about ready to begin!

FAMOUS LAST WORDS....

Some initial trials with the first design of wheel produced some severe problems with getting it balanced so I have had to go back to square minus one and try again!!!

After being suitably robbed by friends at the "plans exchange" I have copies of the original drawings and they are scary. What is beneath that slab sided casing is simply wild. I expected the electric steam boiler for carriage heating, the resistors in their air cooled top hat were well known. But what came as a complete surprise was the switching. I expected air blast switches or sealed bath type. What they used were liquid mercury and oil insulator with plunge carbon contacts. Needless to say I will not be using this system...

Well as I have always said "the English do business at the Pub".... Yesterday evening at the Beer Festival five people sat down with half pints of various brews and looked over my drawings for the EE-1, and by the end of the second set from the band on stage -we had worked out a means of building the wheel. So far 4 polite enquiries to local model engineers had resulted in 3 polite -but definite refusals and 1; "You must be mad!"

The new method of making the wheels will only require some turning of the final flanges but entails me producing a jig to make the spokes from. These are lengths of 5mm square bar with the "fork" legs welded at 45 degrees to them. The fork legs will have an M3 tap hole to contain the Quill Drive spring cups -thus giving the "garland" of 12 springs. The completed tridents will then be welded to the central boss, and then the rim and flange array, (simply a 8mm "washer slice" of 8mm plate), silver soldered to it. This will give a more correct wheel and require very little lathe work.

A few days have passed and I have been very busy in the domestic field... But, on a typical Summers Sunday Afternoon I have started work on some "test" constructions for my wheel. The following shot shows the "best wrong drawing" and the experimental tridents placed on it. These are simply pieces of 5mm sq pine from the bits box.

See Picture 2

What follows is probably going to reduce "The Professional Engineers" to a laughing heap on the floor -but as a poor newbie to metal working -I cannot see any other way to do it...

At the moment I have a small 2 1/4 inch lathe and a small 10mm milling machine on order. Allied to this, I have ordered a 75mm rotating table and compound table for the mill, a face plate and 10mm drill chuck for the lathe. Both of these are rather small for model engineering work at 150Watts each -but they will be my first, (and probably only), mill and lathe(!)

The Plan

1: Construct the jig to make the trident out of 3mm plate and 4mm bolts. Tridents are made from 35mm lengths of 5mm sq plus 25 mm lengths cut with a 45 degree angle. Start of trident is 15mm from the end. Weld tridents.

2: Construct the jig to make the wheel out of 3mm plate (120mmx120mm) and 4mm bolts -use the pre-bored 3mm holes in the tridents to hold the spokes to the plate. Weld spokes to 20mm AF hex bar at centre

3: Construct a circular plywood sandwich with the spokes in the middle and bolt this to the rotary table. The plywood is used to damp down the vibration. Mill off the excess to produce a 93mm diameter .

4: Make the wheel rim. Find the centre of a 100mm plate of 8mm steel. Place the plate on the rotary table. Mill the excess off to leave a disc of steel 99mm in diameter. Next mill a section out of the rim 2.3mm wide by 6.4mm deep -thus giving me my flange. Decrease the radius of the cutter to produce a 4mm thick ring. Mill out the ring.

5: Place the spoke assembly in the freezer and heat the rim on the Wok Burner. Place the heated rim over the frozen spoke assembly and (hopefully) the spokes have contracted and the rim expanded and the gap is more than 0.3mm -thus I have a fit!!!

6: Weld rim to spoke assembly.

7: "True" and centre completed wheel on face plate of lathe.

(I will let you know how I get on)....

Well after several evenings of "flat thumb" due to track laying. I have returned to the problems inherent with building this loco. Having worked out how to build the wretched "snowflake" wheel I was left with the problem -how did I get power to it???? I had heard of Muffett Gears from a forum and I downloaded their catalogue, and poured over it.

Modern gears are quoted as MOD -short for modulus so if a 1 MOD gear has 20 teeth -it is 20mm wide.

I initially started with the 1 MOD gears (I am a lazy mathematician) and could not find one that worked with the shafts and ratios that I liked. I eventually found what I was looking for in the 0.7 MOD gears... There was the "Bull" gear I needed and a length of 22mm bore copper water pipe would make the tube axle for the quill drive. However, I still had to "climb over the edge" and connect it to a motor. The smallest 0.7 MOD gear I could find had a 4 mm shaft -I could connect this to the drive shaft from the motor. None of the motors I had, or could easily source would fit -most of them have (of course) 2, 3 or 3.2mm shafts.

What I wanted was a motor that was no more than; 50mm long, 40mm wide, a 4mm shaft, a torque rating of at least 200 grammes per cm, and would work between 6Volts to 12Volts.

After two days -I found it in a site devoted to "Robot Wars"...

The method of connection of the motor to the "Bull" gear is, (I am ashamed to admit), something of dog's dinner. The motor drives a nylon MOD 1 gear 20 tooth to a nylon 40 tooth MOD 1 gear this then sits centrally on the common 4mm shaft with two Hostaform 16 tooth 0.7 MOD gears these then drive the "Bull" gear a 100 tooth 0.7 Mod also made of Hostaform. All this plastic gearing does have several advantages -cost is a dividend but that is not the main one! The "Bull" gear will have to be drilled at 6 intervals to take the 3mm drive pins for the Quill drive springs. The main problem I now seem to have is one of cosmetics... The Hostaform gear wheel is of course brilliant white -I have yet to find a primer that will stick to it. Although it doesn't really matter in the great scheme of things I would like to have my gear wheel a nice matte black -so the wheel in front of it shows up better.

The centre of the 100 tooth gear is bored to take a 10mm shaft the axles which the wheels will be fastened to will be 6mm...This allows a slight amount of vertical play. The pins from the "Bull" gear form the 6 arm spider to the garland of 12 springs (6 per wheel) that connect to the 45 degree spokes on the main wheels. The copper pipe actually fits over the boss of the "Bull" gear and will be bolted into it -thus transferring the torque through a fairly meaty part of the gear rather than the centre. (The boss is actually 12mm wide by 21mm thick!!!)

The nice people at Muffett gears sent me one of the 16 tooth and 100 tooth gears to play with -as they could not answer the questions that I asked them(!) The primer that I need to stick to the Hostaform gears is a "red oxide" 2 part epoxy one used for metallic paints. I had experimented with:

Conventional automotive grey spray can primer -which dripped off...

Finnegans "No 1" which stuck -but it rubbed off...

I tried thin superglue brushed over part of the surface, (the primer stuck to that) -but the superglue cracked and fell off...

I am now in the process of getting the correct rating of spring for the garland for each wheel. If the spring is too strong, then I might just as well rigidly fix the gear wheel to the axle. If it is too weak, then the springs will crush and the same thing happens. The trick is going to be finding the spring that is the correct width (5mm) and the right compression rate (about 150 grammes per mm) with a very low number of turns. This means that the spring can compress quite a way before it binds. There are going to have to be 6 springs winding clockwise and 6 springs winding anticlockwise. Thus the springs take the torque regardless of the direction of rotation and the deceleration forces are absorbed by the springs.

The next shot shows what I call a "thought model" for this -the spokes are 5mm wood, the hub is a stack of washers, the gear is an actual grey test sprayed gear and the springs are wrapped around 3mm bolts. The whole thing is held together with bits of Blu-Tac! The distances are roughly right and the size of the wheel is correct at 90mm with the 70mm "BullGear" behind it. This sort of mock up is how I get the "best wrong solution" for the problem!!! But on the other hand it does test; how things will look, how easy it will be to produce and what the likely problems are going to be...

See Picture 4

Thanks to the thought model I have decided how I am going to do it... There will be spring cups soldered to the spokes and there will be a 3mm bolt projecting out of the spoke. This will act as a shaft to a length of brass tube with a spring cup at the other end, this retains the spring throughout all motions, (hopefully!). The spider arm from the bull gear, (another 3mm bolt), passes through a hole on the other spring cup and thus passes the torque to the rim of the wheel.

viz:

Well despite that I cannot see straight due to the "bug" that has infected me -I have continued to build the jigs for the wheels. The next shot shows the assembly jig for the trident and a test piece made from it (in 5mm pine).

See Picture 6

The next jig is the one that holds all the tridents in place while I hit them with the welding gun. The tridents in the jig are made from the jig in Picture 6. I admit it was with some trepidation that I slipped the M20 washer into the centre and found that -IT ACTUALLY FITTED!!!

See Picture 7

With every new type of locomotive that appears there was always some patent or other attached to it, the Webb compound is one of the more (in)famous ones. I had, through my reading, been made aware of a patent for this locomotive and sheer curiosity made me fork out my £3.57p for a copy of the patent from H.M.P.O.

After having studied it for three days I am of the opinion that Sir Vincent Raven was either totally barking mad -or a certifiable genius.

One of the problems you get with a symmetrical locomotive is the fact that the front bogie acts as a guide -but the rear bogie tends to flop around all over the track... What this patent describes is a method of turning a symmetrical loco into a non-symmetrical loco, depending on which way it is going!!!

The EE-1 used a std (for the time) front and rear bogie connected by radial arms from the position just in front of the central driving wheels. There is a central pivot in each of the bogies.

When the loco is moving forwards a pneumatic piston moves an rod pushing a fork against the rear bogie pivot arms -thus stopping it from moving. At high speeds the same thing happens to the front pivot. Thus the loco becomes more rigid at higher speeds. The only thing I have ever seen like it is the Citroen SM in which the steering became progressively heavier at higher speeds to stop the driver doing "silly things" at the wheel.

This so very wild and wonderful -that I am going to have to figure out some way of getting to work in the model. At the moment I am debating whether to admit defeat and start looking into PICAXE programming to control everything. There is going to have to be three sets of ESC's to run this thing as it is...

viz:

In one of my previous jobs I used to be the chief programmer... So having sat down with the manual for my milling machine and lathe I have produced for myself a series of instructions. My father always used to wonder at what was on the tapes for the "NC" machines at Derby Works -so out of respect for the people who laboured so hard with primitive machine languages here is my "NON NC" program!!!

FIND CENTRE OF 100MM BLOCK

DRILL 3MM HOLE, BORE TO 7MM

DRILL TWO 3MM HOLES FOR CARRIER BOLTS

LOCATE AND CENTRE BLOCK ON ROTARY

CENTRE MILL HEAD ON ROTARY

TRAVERSE PLUS X TWENTY SIX TURNS

FIT 3MM CUTTER TO MILL HEAD

TRAVERSE PLUS X SIXTY DIVISIONS

SET GEAR BOX TO HIGH SPEED

WIND DOWN HEAD TO SURFACE OF BLOCK

ENGAGE FINE FEED AND FULL SPEED

WIND DOWN MILL HEAD TO CUT THROUGH TO MDF

ROTATE 360 DEGREES

WIND UP MILL HEAD

POWER OFF

TRAVERSE MINUS X EIGHTY DIVISIONS

WIND DOWN HEAD TO SURFACE OF BLOCK

ENGAGE FINE FEED AND FULL SPEED

TRAVERSE MINUS Z ONE HUNDRED AND TWENTY EIGHT DIVISIONS

ROTATE 360 DEGREES

POWER OFF

TRAVERSE PLUS X TWO TURNS

INCLINE ROTARY PLUS TWO DEGREES

FULL SPEED

TRAVERSE MINUS X TWO TURNS

ROTATE 360 DEGREES

POWER OFF

INCLINE ROTARY MINUS TWO DEGREES

WIND UP MILL HEAD

TRAVERSE MINUS X TWO HUNDRED AND EIGHTY DIVISIONS

WIND DOWN MILL HEAD TO SURFACE OF BLOCK

ENGAGE FINE FEED AND FULL SPEED

TRAVERSE MINUS Z ONE HUNDRED DIVISIONS

ROTATE 360 DEGREES

TRAVERSE MINUS X ONE HUNDRED AND TWENTY DIVISIONS

WIND DOWN MILL HEAD TO CUT THROUGH TO MDF

ROTATE 360 DEGREES

POWER OFF

Well hopefully at the end of this I should have; a circular "tyre" with a 2mm flange, a 2 degree cone angle, the rim which should be 4mm thick, and there is then a 3mm thick inner flange to locate the spokes onto...

Well a couple of more weeks have passed and after several hundred pounds of investment -am I any closer to starting work???

NO!!!

But I now feel that the bulk of the design work has been done. The steel for the wheels is on order and I am now in a position to start experimenting with off cuts of wood to get my technique as good as I can before start for "real". The chassis design for this loco is in two very distinct and totally different parts. The first is for the driving wheels -which will have to swivel to take the corners and the second part which is the bogies which will steer and then lock, (depending on conditions). All of this will have to contained within a scale size plate frame chassis -which will have to look as if it is the sole method of containment, whereas in fact it is more "decorative" than functional. In reality only the front and rear bogies and the central driver will connect to the chassis the outer driving axles will transmit their thrust to it via central spine hinges. This means that the axle boxes are going to be wider than required -and the hole in them will actually be a slot for the outer axles.

See Picture 9.

The steel has finally been delivered and "fun and games" begins!!! My first trial and assay, to see what I actually had, simply involved placing the pieces of steel where they would be in the model, and surprisingly, despite the "cubist" look of it -it all seems to be "right"!!!

See Picture 10.

The next step was to make the hubs for the wheels -this involved drilling an 8mm hole through the centre of each piece of 20mm dia bar. This being the first time I had ever done anything like this since grammar school (and I never used a lathe in metal work either!) -I took it slowly. On average it took me 30 minutes to bore the hole all the way through. I did remove the drill and brush it out every now and then... I still have no coolant pump -so I improvised a drip system. I doubt that Motil 1 was ever envisaged as a cutting oil -but it seems to have done the job well.... The next shot was taken at about 10 pm -so the light is pretty bad -as were my eyes at the time!!!

See Picture 11.

The problem with this wheel is the fact that it has: 6 spokes, each spoke has 2 forks, and there are 6 wheels to make. I have just collapsed in my chair after having sawn 36 spokes out of 6mm sq bar and 12 forks. YES the first wheel is now in pieces!!! My wrist is absolutely "killing" me and I have gone through 3 Junior hacksaw blades -but here is the first steel snowflake...

See Picture 12

The hub is going to have to be lathed to the correct shape -it will have to be reduced in diameter at the top and tapered at the bottom.

That is the actual size of the tridents et al.

Time passes and I have now finished FOUR snowflake wheels -these are the four outer driver wheels that will pivot, hence they have shorter length hubs -to give them more lateral play. These have been daubed with red marker the other two have been daubed with blue marker. The red shows up black through the green goggles that I wear for soldering -the blue shows up as blue(!) I have had to call a halt to the soldering at the moment as I am out of the correct grade of silver solder -but then so is the supplier...

See Picture 19.

They have been nailed to the sacrificial jigs despite extreme care with their position -the jig is simply there to hold them in place while I solder the hub joints. I doubt there will be anything left of the centre of the jig by the time I have finished!!!

Now that I have the time to play with other things I have been "practicing" my skills with the milling machine and the NON-NC program. Well initial experiments went well -but it did prove that my choice of practice material was very wrong!!! I began with a scrap square of MDF, centred it and began cutting. By the time I had got 5cm I knew that I had made a mistake... Due to the position of the coolant fan for the motor and the position of the shelf above -I was working in a sandstorm of brown wood dust!!! Nil Desperandumn I continued and at the end of about 5 minutes I had cut a washer with a flange and covered everywhere in my work shop bench with a thin layer of brown dust. It was of course one of those days when you get up in the morning an put on a nice white polo shirt. It has gone through the machine twice -but you can still see....

Having had nothing to do but rack my brains on how I will do things... The problem of how to detect when the loco is cornering, (so that I can lock and unlock the trailing bogie), has been one that has been troubling me for some time!!!

It had to be sensitive enough to actually tell when the front bogie had hit a curve but not to be so "twitchy" that it flicked in and out as the bogie rattled along the track work. I had discounted the use of a magnet and reed relay for doing this as it would not be sensitive enough and similarly an LED/Photodiode system with a slot would be too twitchy to work well. I had almost worked out a system using a potentiometer when I took my ruler in my hands and it bent...

And that is when it hit me.

What I wanted, was a substance whose electrical resistance -changed as it was bent. There exist several substances that fulfill these qualities but none of them are "shop shelf" items. Quantum Tunnelling Composite [QTC] can be described as a sponge with tiny carbon grains in it. The more you squeeze it, the more grains touch -the more it conducts.

So, at the end of a mad half hour of flipping through pages, I have the design in front of you.

viz:

The bogie arm rotates an eccentric squeezing the QTC until the voltage is enough to trigger the reed relay, (and hence the power relay), this triggers the solenoid that unlocks the rear bogie. A reed switch and magnet array on both bogies tells the system when both bogies are straight and this then locks the rear bogie.

All of this weekend I have been playing with plywood(!) I want a grade that is flexible enough for me to have the nice gentle curves at the front and rear of the loco -but strong enough to act as the former for the plastic sheeting that will be laminated onto it. Eventually I found a length that fit my criteria at the local model shop and went home with it to begin marking it out and sawing it to size... What has surprised me once I cut out the side panels was how cramped it is going to be inside the model. There is barely enough room for a 6 Volt battery at either end and if I am lucky I will be able to squeeze in some relays too!

The 3mm marine birch ply that I am using is not the "nicest" of ply to cut -I have extracted more than few large splinters... However it is strong and flexible and I have re-enforced the straight edges with 5mm sq pine strip. The centre section which will house the fixed axle is strengthened with "vanity blocks" and a some off cuts of MDR and pine strip. It may look messy -but it is rather strong!!! This will be the first loco in which the bodywork is simply a "cosmetic"shell -as all the torque and torsional forces will be carried through the side frames of the loco.

See Picture 21.

A closer shot of the centre section.

See Picture 22.

Hopefully tomorrow I can sit down with my saws and produce the parts for the tops and the ends. The ends of the loco are 4mm narrower than the centre and taper from the start of the bonnets to the buffer beam.

Saturday night was spent chewing pencils and frantically rubbing out lines -in short circuit design... Now that I know what has got to be crammed into the plywood bodywork I can begin sourcing the relays of the right power rating and (more importantly) of small enough dimensions to fit!!! The Maplins catalogue has some useful ones -but they are of rather larger size than I would like -so it looks as if the RS on-line catalogue will take some examining.

Here is the circuit diagramn.

The main on/off switch and the fwd/rev switch will be on the roof as per normal. The ESC will have to sit in the "top hat" and the main power relay, the fwd/rev relay and the lights relay will have to be fixed the roof in each of the three "motor compartments" of the model. Not exactly the nicest layout -but to be honest I am afraid that is the only way I can see to get it to work... The battery and the bogie relay will occupy the bonnets at each end. They are going to have to sit on some form of tray that I can slide in and out of the bonnet cavity, and I have this horrible feeling that I am going to have to build some sort of plug and socket assembly at the end of the tray...

While I am at it, I suppose I had better sit down and design the switching system for the front and rear lights. When I built the NYC "S"Motor all I had to do was a simple fwd/rev for the lights. Here I think that this is going to be the "queen of the fleet" it had better have lights that really worked and display head lamp codes that the original (possibly) would have displayed... There were ten standard head lamp codes A B C etc(!) and of course R (for The Royal Train). Having flipped to the right pages on my hand me down copy of the Midland Counties Railway Signalling and Locomotives (part 2) -I have selected the following:

A: Express Passenger Locomotive pulling passengers.

B: Ordinary Passenger Locomotive pulling passengers.

D: Empty Passenger train.

F: Express Goods.

H: Through Goods or Light Locomotive

viz:

So, having gone sufficiently clockwise around my loop I can now legitimately disconnect the loco, change the lights from A to H zoom around to the back and flip over to B or D. I can use F if I am pulling wagons, (oh! the indignity of it....)

Several people have asked me to explain how the rear bogie lock will function in practice...

There will be a sort of mousetrap bar with a slot in it that will hold the rear bogie arm in place (1). When the QTC is crushed the relay that it feeds closes the N/O contacts and power is fed to the solenoid. This lifts the mousetrap bar (2). The trick is -is that the rear arm has a reed relay on it that provides the Earth connection for the relay, when the rear bogie arm moves the reed opens breaking the circuit to the relay and the solenoid drops the mousetrap bar. But, as the arm is now on a corner, the arm no longer sits in its slot and the mousetrap fails to close (3). When the rear bogie returns to a straight section of track the arm moves into the slot and the mousetrap bar falls holding it back in place, the magnet thus closes the reed and resets the system ready for the next corner (4).

Yesterday evening was spent with sheets of soaked balsa and aero glue. I have cross laminated the plywood sides of the body and bent the wet balsa over the curves of the ply and (hopefully) it will all be strong enough to take the strain of being "plated" with ABS sheet. The roof spars are glued into place and it seems that there will be enough room in the roof cavity for the various relays and what not. The next thing to do is to construct the roof with its "top hat" for the coolant fans intake louvres.

See Picture 26.

In reality this is not too far from the truth as the top hat contained the resistors for the motors and was force cooled. In the model there will be three old 486 CPU fans and some ducting, (also made from balsa sheet), that will direct the air to the thee cavities in the body where the motors, (and more importantly), where the ESC heat sink will fit. I have decided to opt for a simple PWAM ESCs using a TIP147 power IC in a T0220 case -which simply three legs and a 3mm bolt hole that I can screw a finned heat sink onto!!!

See Picture 27.

There comes one point in every project that you feel like you could just go into a dark corner and just SCREAM!!!
 
This point was reached yesterday afternoon....
 
Well I had my nice jigs, all the steel was shiny in the sun, and I had a fresh cylinder of propane rather than MAPP gas -as I did not want to melt the already soldered tridents. I was all set to start soldering the tridents to the hubs. I was worried that the centre of the jig would burn through -in the end none of them did. The problem that has arisen is one that I could never have foreseen. As the temperature of the centre hub rose to red heat the MDF around it caught fire, this was not unexpected!!! The soot from the burning MDF settled on the still unsoldered steel and stopped it from soldering. Thus I had, (what I thought), was a good layer of silver down each side of the joint -but in fact it had not stuck...
 
Added to this the whole thing while it cooled underwent a "cheese sandwich" and the edges of the MDF curled up -breaking any still soft or molten silver solder joint.
 
I have a nice collection of wheels -none of which are usable. I do in fact have one with six tridents attached to it -but the joints are so pathetic that I can twist them with my fingers. I am going to have to re-think this and probably scrap what I have done. Still looking on the positive side, I now know how NOT to do it...

At the moment I feel that I am looking at fresh order of square steel rod and start sawing again. I am not a good welder but it looks like 1.5 mm rods at 60 Amperes will have to be used -plus an awful lot of grinding!!!
 
I hope that the third attempt to make these wheels will work. Because if it doesn't then I don't know where I will go with this project. I have gone back to the drawing board once with these wheels and they are the major part of this locomotive. If I had decided to built the Italian equivalent, then it would have had "normal" express spoked wheels with 18 radial spokes and I could have bought these as castings. I will have to consult with the "Oracles" at the pub tonight to see if we can all sort out; where I am going wrong, where I can go from here to get back on track...

Well the report from the gods of "The Welding Institute" is that I put far too much heat into the work!!! I used a big fat propane flame rather than a short hot MAPP gas one... Yes what I have done is recoverable -but in their opinion it would be easier to start afresh(!) The next jig is going to be made from 5mm thick steel plate with 4mm bolts and well oiled with "spatter stop". I harbor no illusions as to the quality of my welding -it is strong -but very messy and ugly!!!

The hub will have to be bored and then Aerocraft Grade Titanium 3mm threaded inserts screwed into both the hub and trident. The gap can then be closed with silver solder -thus is will look pretty and actually be far stronger than if it was 6mm thick steel... And because the join is (nearly) self supporting it can be braced on top of a clay mound and that will hold it in position while it gets the torch treatment. The problem is drilling a 3mm hole down the length of one of the now very scorched and flux covered trident -this will means making some form of sabot to hold it in the jaws of the lathe while I drill. But that should be pretty easy?

This is going to take some time to do -I estimate a week of evenings to get the tridents back to their nice shiny state -but "nil desperandumn" this time it is going to work, (please)...

I have yet to complete the construction of my home brew (hah!) SUDS unit for the milling machine. The tray that the SUDS will flow into from the cutting head of the milling machine, is something I recognised from my childhood, and we unearthed it from the garden. It is the pressed aluminium lid from a Hoover spindrier. Since we found it it has been; a bird bath, a potting tray and is now elevated to the lofty position of SUDS drain tray -in this respect I suppose you could say that it has come full circle. The pump unit is a converted yacht bailing pump and is capable of 5 litres per minute continuous with an overload factor of 25 litres per minute for 10 minutes(!) The cutting fluid is 95% water and 5% Castrol Coolidge -the Wurth cutting oil is cheaper and cleaner -but to me it doesn't smell "right". Let me explain what I mean. My late father worked on the railways and naturally it sprayed everywhere and his work overalls were spattered with it. It stuck to his skin and was part of his natural being until he showered at home. When I was eight I contracted a virulent strain of measles, (it later became termed as "the double measles" epidemic), and like several kids in the neighbourhood I went blind and deaf with it for several days. The sight recovered after about a week -my hearing never did. But during that time when my father came home he would hold my hand and I could feel the steel shavings in his paws and smell the SUDS on his skin. So, as you can see -the smell HAS to be right...

While I am busy with the SUDS pump I have been examining the bogie wheels which will have to be milled from 8mm steel plate. At first sight these look extremely strange -and not at all like the ones that were fitted. However these, (according to family in the Darlington area) -were the wheels that were destined for this loco and her sisters. But there were problems with making them, so "conventional" eight spoke tender wheels -were fitted instead. The design for the bogie wheels makes sense if you think of them as vibrating plates, (Chladni Plate resonance), and the holes and slots alter the resonance of the disc. Another example of this would be the wooden centres fitted to the wheels of "Maunsell" coaches, in which the wooden centres were supposed to dampen the wheels and make them run quieter, (which they did), but it was more the discontinuity in the shape of the wheel, (rather than the wood), that was more effective.

This is the original proposed design of wheel for this locomotive -which for some reason reminds me firmly of a Mecanno wheel -but also of the racing wheels fitted to the Bugattis and Auto Unions of this period!!!

The clocks have changed and I have been busy trying to work out how this thing should corner.... The maths is actually quite easy -the problem is getting all the "gubbins" in between the chassis rails to fit(!) The "Sub Chassis", (I suppose I should call it?), is a central spine which simply has sectioned 22mm water pipe fittings to grasp the bull gears, with vertical sheets of 2mm thick brass through which I mount and contain my gears for the bull gear. There will be compensator levers between the front and rear driving axles that will "pre-load" via springs the other axle to the correct direction. This "should" make it corner easier. I have the idea that I should also arrange some sort of locking mechanism for the compensator levers while the loco is on the straight to prevent too much "nosing"(?)

I have tried to give some sort of balance by flipping the central motor to the other side -thus the chassis will only need some lead shot enough for the weight of one motor. The gear work on the two external axles is moved towards the central one to give space for the fitting for the front and rear bogies. This is the first model that I have ever found where space is at a premium...

See Picture 30.

Well the end of another wet Sunday has produced thirty six 3mm holes in the tridents and six hubs each with six 3mm holes. This was perhaps the most difficult thing that I have done. I know that I will never make a Model Engineer -but the amount of drill "wandering" was enough to make a grown man weep!!! This is despite the hub being held in the jaws of the re-mounted lathe chuck and turned using the rotary table. The entire mish mash looked very wild and was incredibly difficult to position on the table of my pillar drill, and there were several times when I was convinced the whole thing would topple!!! The pins to help hold the tridents to the hubs are 1cm lengths of 3mm Titanium "piano wire" and I have the scars to show that all the pieces were hand cut... This now raises an interesting question -do I continue on my path and silver solder the tridents to the hubs -or do I epoxy them together? Epoxy has the great virtue of that fact that no heat is involved. Thus there is no chance of disturbing any of the prior silver solder joints, and once it has set it -will almost as strong as a metal joint.

Either way I have built a new jig from sheet steel this time...

See Picture 31.

As you can see it has a central bore hole through which the inner hub centre sits and it has three bars to hold everything in position. I will consult with; "The Welding Institute" on Wednesday morning as to the best method to proceed from here. I think that I will need to wrap 0.5mm Easi Flo solder wire around the pieces of piano wire and paint them with flux. These will then wedge nicely in the holes and I, (hopefully), should have some molten solder in my joints -by the time the externally applied solder reaches the hole?

It is with great personal relief that I can announce that I now know the technique involved in producing a snowflake wheel. So far I have had a 50% failure rate in test of previous attempts but now we have a strong rigid snowflake that we can build on!!! I tried Epoxy resins in the stud hole combination and this does show great promise -but for Gauge 3 is is still too weak. The SIF BRONZE process is the one to use and it works well. The bronze flows around the pins and sucks up nicely into the holes. The only problem is that everything is running at orange heat and there have been "a large dictionary of WORDS" spoken when the jig and the hub have distorted and the use of a hammer is required to free the hub from the jig. NO I DID NOT STICK THE HUB TO THE JIG!!! A file and oiled emery cloth took the burrs of the hub and some more "anti spatter spray" used on the jig after it has been pounded flat again...

At the end of the evenings work I have a workshop that stinks like a drain, (MAPP gas), two snowflakes and big grin on my face!!! I was approaching the point where I was beginning to get very worried that this might actually be impossible to do with "Kitchen Sink Engineering" level of technology.

Well at the end of Friday we have a small stack of steel snowflakes -some of which may need some pounding with a hammer to get flat... The experimental tests with the bull gear have commenced and I am happy to say that the gear does fit where it should do. The 3mm bolt holes on the rim of the bull gear line up tangentially with the centres of the tridents. The quick spin in the lathe shows that some of the spokes have a 1-2mm run out -but I am not sure if I should lathe them flat or pound them flat!!! The next step will be the cutting of the tyres for the spokes. This is the bit that will probably make or break the project.

The wheel plate is 8mm thick and the spokes are made from 6mm sq steel...

The next step means digging out the Milling machine -something that is (as yet) an unknown quantity with me. My late father said: "There are Lathers and then there are Millers". I do not know as yet which camp I fall into -since my only test run with the Milling machine ruined my favourite white polo shirt....

Well after an afternoon of teeth jarring vibration and showers of swarf chips I can tell you -that I am not a Miller. However I have started cutting the first tyre for my wheel and I have promptly broken the milling cutter... Possibly I started with the one that was too small for the job (3mm) and I seem to be having more success with the 5mm cutter. I also think that I have stripped the central gear in my rotary table!!!

See Picture 32.

There was a famous line from a motto that is very near the knuckle for me at the moment;

"If it doesn't work -Hit it with a BIGGER hammer"...

I have gone back to using my lathe to make the wheel. I suspect that what remains of the "blank" is now totally useless, but it will serve as an educational piece -and I can always order another. I handed the hideous remains of my "blank" to a friend who commented; "I see you had better luck with the angle grinder!" I had lopped off the corners of the "blank" and then ground the edges with the angle grinder. I had a roundish wheel like shape in 5 minutes after days of madness with the Milling machine. Centring the round in the 4 jaw chuck by using the drill chuck and a 7mm drill was the easy part. The lathe spun the piece up to speed and we attempted to cut out the centre. And I have to admit that it is going "slowly but surely" at the moment. I don't have any form of boring bar, (something else I didn't think I would need to buy), so it is a case of cutting out enough room on the blank to get the cutter point into the metal. The cutter is 6mm square -so not a lot of depth of metal is being cut...

Well after three days I have a ring of steel, (that may possibly be concentric in some place!) -and a non functioning lathe... No -I have not ruined it, ( I hope!!!), but the problem is electrical in nature -i.e. it won't go round.... The method of parting the centre from the ring is one I am not proud of -but it worked faster than anything else that I had tried. This involved putting it back onto the rotary table and chain drilling a circle of 8mm holes close together around the interior of the ring and then milling away most of the metal until it was held onto the centre by 1mm to 2mm of steel. This left me with an 8mm "trench" into which I could get my 6mm sq cutter. Then I reloaded the blank into the 4 jaw, spun it up speed, (in reverse), and I hit it with the cutter. I have worn out one of my indexible cutters in the process and I have learned a lot by doing so. I now know how to cut my tyres for my wheels -so the £1.30p that the cutter cost is a good price to pay after so many weeks of fruitless endeavour. (All I have to do now is get the lathe to work again...)

Well it is now Saturday Lunchtime and the lathe now works again after over an hour and a half of icy cold work. The only source of heating in my shed was 25Watt soldering iron plus a large and seemingly too rapidly cooling mug of tea... BUT, after having cleaned up the oily swarf, (which has caught fire on a couple of occasions!) -here is the first tyre clamped in the 4 jaw chuck. (Sorry about the shot -but it is rather foggy here...)

See Picture 33.

As the saying goes; "We have separation"... The plan is to turn the inside smooth and then fit the 3 jaw and wind out the jaws and then turn the outside of the tyre for the flanges and treads. This raises the question of the "correct" shape for the flanges and the coning for the treads... I come from a colonial back ground and our treads where perfectly flat (i.e. zero degrees) and our inner flanges at 10 degrees with a zero degrees outer flange. The Gauge 3 std says that they have to be cut to a 2 degree tread and a 10 degree inner and outer flange profile. I am going to have a "go" at the Gauge 3 profile, even though this will entail the purchase of some more equipment for my lathe...

I am going to attach the spokes to the rough finished tyre and then "true it up" on the lathe. Currently the hubs have a 7mm hole through them that will have to be opened out to 8mm for the axles to fit. I have also got to drill the hubs to take the pins through the axles.

At the moment the outside of the tyre is a mess of grinding marks...

Monday night -after an extremely cold Sunday afternoon in my shed. The spokes got a quick kiss from the angle grinder and then turned on the lathe until they were the correct size to fit into the tyre, (80mm), The assembly was then "unified" with industrial strength CA, and then the tread and flange "roughed out" on the lathe. The net result is shown below:

See Picture 34.

One down -FIVE more to go!!!

Sunday Evening, well it seems that I can make one wheel at the rate of an evening and two afternoons -this equates to one per week. I now have my second wheel, and I can boast that I am now 1/3rd of the way there!!! Looking at the one wheel I knew it was big, but somehow seeing the pair of them with a makeshift axle, (a length of brass tube), between them has really brought home how large these wheels really are... They weigh in at around 350 grammes each and they really do seem very hefty. I tried to cut a flange on the first wheel but I didn't try that on the second, (that can wait!). They both sit in at 96mm diameter and to be honest with you I feel "rather chuffed" I was worried that I could not produce a "pair" -but it seems that I can....

See Picture 35.

The spokes are still slathered with burnt flux and some surface rust because of it. The next stage will be to get some "rust eater" on them and then dip them into enamel. This should hide a multitude of sins, and look a lot prettier! Well I didn't "dip" them more like slop them! I used a 4x1 paintbrush and a tin of trusty (!) Hammerite primer. I stirred and shook the tin well -but despite this it seems that my wheels are now a fetching shade of beige... I have to apply another coat -but in the end it doesn't really matter what colour the primer is -as long as it sticks to the metal.

See Picture 36.

I seem to be following my consumption estimate and going through one cutter per wheel. I am now half way through my production run and I am awaiting delivery of five more cutter tips -plus a boring bar. The latter will be used to "open out" the 13mm hole that I have drilled through the centre of the bull gear. This needs to be about 15mm, (I think), to allow a suitable amount of "float" between the bull gear and the bosses on the driver wheels.

While we wait for the postman to deliver the stuff I have been looking at the problem of the bogies. They need to be cut from the same thickness of steel as the chassis plates -so they are going to be 3mm thick. The bearing plate for the bogies will, (more than likely), be welded to them -this should give a more rigid structure. The original plan was for them to a basic Bissel bogie and I still think that this is the better option for them. The main problem with a Bissel bogie is that the cornering is only really "correct" for one particular radius, but since I have only two radii to worry about I can allow for this.

The "mousetrap" bar will be at the ends of the loco -this will give a more "positive" capture and thus lock the bogie at the fore and aft positions.

Now that the Christmas and New Year madness is over ,(and I still haven't had my stuff delivered), I can return to my loco. The time draws near when I shall have to start to build the relay and switching boards for my loco -even though at this point in time it only has three wheels... These are going to have to sit in the bonnets at either end of the loco and,(somehow), share the same space with the batteries. The lamp codes are going to be generated by a simple diode matrix -although the layout will look extremely messy on the boards -I think that it will be fairly foolproof. The voltage drop across each of the diodes, (ye olde 1N1001), is 0.7Volts -so the 12 Volts feed will require a suitable dropper resistor.

The lamps 2 and 4 will have to be dual Red/White LEDs. In the diagram above (neree1pic23.jpg) the Lights relay, (a DPDT), will trigger two DPDT and one SPDT reed relays located at each end of the loco. The selector for the lamp codes will be a very simple 6 way single pole switch. RS do a nice one for £0.95p that I can hide in the central cooling tower -along with the central 10K speed control potentiometer.

Well while I wait for parts to arrive... I have put the roof and the coolant "top hat" onto the body of the loco. The wiring for the central ESC heat sinks (and 2N3055s) has been built and installed. I admit to some trepidation as I firmly sealed over the roof and then waited to cut through it (whilst knowing that the wiring was just millimetres below my knife blade). If I sliced through the cable with my Stanley Knife then there was no way of replacing it bar ripping off the whole thing and starting again...

Here you can see the completed roof, (plus hole).

See Picture 39.

The colour coding of the cables is as follows:

Orange (+) and Blue (-) are power to roof top fans.

Orange (+) and Yellow(-) are the switch supply to the On/Off relay.

Orange (+) and White (-) are the switch supply to the Fwd/Rev relay.

Red (+) and Black (-) are feeds to the ESC system.

Blue (/) and Yellow (\) are returns from the ESC to the Fwd/Rev relay, (they will be DC of variable but differing polarity).

Here you can see the "Top Hat" sitting on the roof with the side holes for the coolant fans louvre intakes cut out. The central square hole will house the on/off and fwd/rev switches plus the A to R light selector switch.

See Picture 40.

A few days have passed and the "Top Hat" now has louvres and some of the loco has started to be plated with a mixture of black and white ABS offcuts, (this is a good way to get rid of them!). The louvres for the top hat are made from my favourite source of strip wood -yes they are lollipop sticks! After I had fitted the last layer of balsa wood to the roof I looked at the fans and thought : "How interesting they will be for small fingers to examine" and so I put a couple of finger guards over them. These are actually circular plastic webs for small children to experiment with sewing on. I have used the larger square ones as shields for the rotating parts of the Heilmann.

The first shot shows the painted top hat and the projecting 3mm bolts with "glass insulators" for the pantographs.

See Picture 41.

The next shot shows the front of the loco. The foundation work for the pantographs is complete, the visor will be installed over the windscreens and the sides then epoxied onto the plywood.

See Picture 42.

Finally... The parts have arrived and some work can now begin on the control aspect of the loco. The "Top Hat" has been drilled and the on/off and fwd/bk switches installed. These may look somewhat "petite" but all they have to do is take the switching current for the power relays. If I fitted a 16A DPDT switch in the roof, I doubt I could flip it without pushing the loco of the tracks. One of the problems that I am going to have with this loco is the speed that it will travel. There is no point, (in my mind), building an express loco without it having the capacity to at least look as if it is doing "express" speeds. This means some form of stopping the loco without having to "catch it" and flip the off switch. Despite is very poor performance out in the garden I do like Infra Red control. It is simple to build, and simple to maintain, plus unlike RF systems it is short range and thus not subject to wide range interference.

So, after a Friday evening and a Saturday morning -the soldering iron has produced the three following circuit boards. The picture below shows (left to right) the IR "Key Fob" two channel controller, the 2 pole 6 way switch and diode matrix for the lights, the two channel programmable IR receiver. The IR system are kits from Velleman. The lights switch and the sensor for the IR receiver will be mounted in the window of the loco. The first channel will of course be off , while the second channel I plan to use to raise and lower the pantographs... As there is not very much room in the roof cavity I have decided to use Memory Wire to provide the tensile forces required.

See Picture 43.

Well the final sheets of ABS have been ordered from Garden Railway Specialists. This will provide enough length to cover one side in one go. This now gives me the job of starting to carve the panels and such like that will adorn the plated sides. typically enough these are not all the same size... Of the sixteen panels: twelve of them are 2cm by 6cm, and the remaining four are 6.5cm by 2 (?) They are at the end of the loco which does not have the, "Hinges and Handles", of working inspection panels and even more curiously they are towards the centre of the loco?? I had wondered if this was a mistake on the part of the drawer of the illustration, but no, it is now quite distinctly visible, (now that know what to look for), on all of the pictures that I have of the EE-1.

As you can see the inner set of panels on the left hand side of the loco are longer, and as far as I know there is no real reason for them being so. The right hand side of the loco has all the switch gear, whilst the other end is simply the steam boiler for train heating.

While I wait for the temperature to rise to acceptable (i.e. well above freezing) in my shed I have been busy carving the pieces that will be "appliqued" to the sides and end of the loco. These have all been chopped out of 60 thou ABS sheet and the curves traced from handy items found locally (for instance the curves on the ends of the inspection panels are from the cheese grater)... The "moustache" air intakes for the "B" end of the loco are actually cut from the Cambrian Models NA24 radiator panel, The hinges and socket keys for the inspection panels come from their NA3 mouldings and the hooks etc are NA4 while the buffers are NA12 (with a little bit of file work!)

The next three shots show the carvings laid out on the side of the loco.

See Picture 45.

See Picture 46.

See Picture 47.

What remains to be "carved" are the roundel, (with its magic number), and the builders roundel at the "A" end of the loco. Then I can start work on the major part of the loco -the chassis....

Well a few evenings have passed and I have been keeping myself warm by the heat of my soldering iron... The single strand cable has been threaded between the ends and the "lights" (actually bi colour LEDS) have been ordered. These are having to come from the USA as there is no "reasonably priced" UK supplier and the total cost of the pack of 10 is less than half of what would have to pay in the UK -including postage(!)

Anyway -this is what I had at the end of Thursday evening.

See Picture 48.

And this is what I have finished up with at the end of Friday evenings work

See Picture 49.

The power feed from the roof top switch to the reversing relay will also activate two DPDT and two SPST relays. Lights 2 and 4 are red/white bicolour LEDS and simply reversing the polarity of the current will make them change, I am only going to use the white side of lights 1 and 3.

Well over the last few days I have been busy in my kitchen. (It is a nice warm place to observe the snow from...) Garden Railway Specialists delivered the ABS sheeting cut to the correct shape, (at the second attempt). This gave me the critical 6mm over hang at the ends of each end of the loco. I stripped out all my nice new wiring, bundled it into a zip bag, then laid my loco on the sheet and drew around it. A few hours delicate work with a Stanley knife produces the sides, and then, (after an evening crushed under kitchen pots and pans), the epoxy sets them into position. The pieces made previously are then CA'ed into place.

See Picture 50.

The three painted drive wheels have been propped up against the side of the bodywork to see the whole effect for the first time. I have hidden the speed and lights control shaft behind the "Builders Plate" roundel at the front of the loco.

See Picture 51.

Well I did say that this was the first model that I had ever built where space was at a premium(!) The shot below shows the two "trays" where the batteries and the associated electrical gubbins will have to sit. The tray is 12cm by 13cm and has a maximum height of 5.5cm. The battery has a dimension of 7cm x 5cm x 11cm -and it HAS to sit between the two chassis rails to balance the loco plus the fact that the "plates" are at the bottom of the SLA. Thus they need to be towards the middle to improve the CofG and also transfer more of their weight to the driving wheels. The main problem is that no matter how I try to rig it I still have "just" enough room for everything, (although I will admit at one stage I was wondering if I could get more space by sawing the tops off the plastic cases of the relays)...

OK -quick guided tour! The "A" tray holds the speed control potentiometer and the 9 pin serial socket to connect to the bodywork,. On the other side of the battery space sits the lights control switch and the four relays, (yes I know there are only two fitted at the moment), that provide the interlocking from the diode matrix, (which is also going to have to sit there...) The "B" tray has the five SPST relays that manage the power , Mousetrap 'A' and 'B' solenoid, POSitive and NEGative lines, and the FANs relay. On the other side of the battery is the fuse board with it's 5 fuses. The huge black lump in the centre is the main power relay, (where that fits I have no idea!!!)

See Picture 52.

Well another weekend comes to a close and I am reasonably happy with the progress. I have two trays plus contents that I can (now) fit into the bonnets at either end of the loco. Some work with a sander was required to get the trays to fit into the holes... Sorry about the truly atrocious shot below -but it has to be done at close range and the flash isn't really much help at that range. The tray has been installed upside down to show where it fits in relation to the wheels. I have spent most of this morning doing extremely accurate drawings with my kit to make sure that everything will miss and not bind on any of the moving parts when the loco corners. The loco body is 13.5cm wide and the chassis rails are 9.6cm wide. This gives me 0.8cm of radial swing on the fore and aft driving axles and, (due to the axle leverage), a lateral play of 0.3cm on the central axle. This should give me a minimum curve radius of 1.46m.

See Picture 53.

I have also been updating my "master plan" drawing which has been printed out on A4 sheets and then taped together. Like most plans the errors have crept in and I hope that all the errors that I know about have been found and corrected. And those that I don't -I hope I will find fairly esay to remedy!!!

Well the mid week of evenings has seen me burning my fingers to the bone with my soldering iron. I have finished the front tray that sits over the "A" end of the loco. Ths honestly the FOURTH attempt to "do" this shot... Because I wanted to try and show the two edges of the tray with the wiring loom I did try close range and simply got a mess of dark wires, SO, at long range, with zoom, I have produced what is possibly my worst illustrational photo...

See Picture 54.

OK. On the left of the shot you have the four relays DPDT that change the lamps code when the loco reverses.

To the right of that is the code selector switch -a 2 pole 6 way.

Behind the switch is the diode matrix.

And above the assmbly is the 9 pin serial socket that connects it to the lighting loom.

On the back of the tray is a tag board that is wired in my normal fashion: RED and BLACK, are DC. BLUE and YELLOW is DC of variable but opposite polarity. WHITE, GREEN and ORANGE are data lines.

The "B" tray with its FIVE relays and associated fuses are going to simply EVIL to wire!!!

(And believe me -it was...)

I have a "design habit" in that I normally operate equipment by "Switching to Earth" rather than "Connecting to Power". This means that The whole of the circuit operates by the connection to earth rather than the connection to the battery. I use this technique as it enables me to have power feeds from unoperating but still "live" cables. On the other hand this does leave me with quite a "fusing" problem. The system I have designed has three separate but interdependant power rails. There is the 12V supply to all other equipment AKA "the FAN" line fused at 3A, there is a 12V dedicated supply for the ESC fused at 10A, and a 3V supply to the LEDS fused at 1A. I have decided to fuse each of the motors at 3A. THUS from the batteries I have a 15A cable into the fuse board, a 10A rated cable to the ESC via TWO SPST relays with three 5A rated cables to the fuse board, (and hence the motors), a 5A cable to the Fans relay and 3A rated cable to the lights system...

Sunday Afternoon, after a weekend of building the pantographs I can (sort of) relax. I bought enough "Servo Horns" to do all eight arms -but then just as I was about to finish sawing the last arm off the seventh set of "horns" -the dammed thing snapped in two... I have altered the standard Henry Greenly patten of pantograph to fit this installation. At the moment I am using some spare springs to raise the arms -but then I will begin the "magic" process of having the arms raise themselves. These will use "Memory Wire" AKA "Muscle Wire" to pull between the two sawn off horns and hence lift the arms. There will be a return spring between the ends of the howns to lower the arms.

The problem I have at the moment concerns the IR relay system. The best place for it is directly in front of the front LHS window. I am not sure if this will "foul" any of the drive mechanism though(?) The basic premise is this: I switch on the loco from the roof top switch. This arms the IR sensor and automatically starts the ancillary equipment (fans lights etc). By clicking the IR sensor I can start and stop the loco -without having to touch it again. Similarly the other channel on the IR fob will control the raising and lowering of the pantograph arms. I now have this insane idea -that I should also make the loco do "whistle codes" for its actions!

Saturday evening after a long week. I have finally sat down and worked out all the "primitive sizes" (i.e. the squarish shapes) that all my chassis work will be hacked from... I e-mailed my favourite metal stock holder with my request for a quote for my Steel and Brass which comes to £66 which brings the bill for this model close to the £150 mark -which for me is extremely expensive!!!

This is what I ordered:

The following are 3 mm thick B.M.S flat
 
BOGIES:
 
TWO    2.0 CM X 17.25 CM
TWO    4.0 CM X 4.5 CM
TWO    13.0 CM X 2.0 CM
FOUR  15.5 CM X 4.0 CM
 
FRAME:
 
TWO  66.5 CM X 5.0 CM
TWO  9.0 CM X 8.0 CM
TWO  9.0 CM X 2.0 CM
 
SPINE:
 
TWO  11.5 CM X 2.0 CM
ONE  13.5 CM X 3.0 CM
SIX     6.0 CM X 6.0 CM
FOUR 6.0 CM X 2.0 CM
 
--------------------------------------------------------
 
THE FOLLOWING IS 3 mm ANGLE B.M.S
 
SADDLE:
 
FOUR 1.3 CM X 1.3 CM X 7.0 CM
 
--------------------------------------------------------
 
THE FOLLOWING IS BRASS
 
BOGIE:
 
SIXTEEN  2.0 CM X 2.0 CM X 1.6 MM (16SWG?)
EIGHT       2.0 CM X 1.0 CM X 3 MM (10SWG?)
 
FRAME:
 
SIX             3.0 CM X 1.0 CM X 3 MM (10SWG?)
TWELVE   4.0 CM X 3.0 CM X 1.6 MM (16SWG?)
 
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They came back with some substitutions for the Brass, (slightly thicker and wider imperial stock sizes), and I am quite happy with that -as it gives me more room to make the inevitable errors in.

I am now at the point where I have all the raw materials to complete the first parts of my model, but the key problem is my shed and the coldness of it. Bundled in my moleskin jacket and my jeans I am not too cold -but the problem is the fact that the steam from my breath mists up my safety glasses. Result -even with liquid soap and spit (two tricks from my scuba diving days!) I do not consider it safe to proceed with a lathe or mill. My wife finds the way I look in my safety specs to be grounds for collapsing into fits of giggles. Yes, they look like something out of "ThunderBirds" and they are like bottle bottoms in thickness -but they will take ME hitting them with a Ball Pein Hammer. The hammer bounces!!! Needless to say I am very happy with them -even if they did cost nearly twice what I paid for my driving varifocals.

Well a few days have passed and the steel (and brass) has arrived. But more importantly the weather has warmed enough for me to return to my lathe. I now have 5 driver wheels and I am looking towards marking out the "Mecanno" bogie wheels. I have printed out and taped together my "master plan" of all the chassis components, feel free to grab yourself a copy if you like....

See Picture 55.

Sunday Afternoon and I have been sorting out and labelling my pieces of steel... What do you do when even "Permanent Markers" rubs off(?) I have sorted the pieces of steel into three piles and arranged them for the following "set piece" photos.

See Picture 56.

Starting from the top there are the two "blanks" for the bogie wheels. The side frame for the bogie. The mouse trap arm. The top arm for the bogie, (which will be welded to the cross plate that supports the two end trays). The Saddle, (which has the two L sections of steel welded to it . The other bogie side plate and (finally) -the remaining two wheel blanks. All of this is 3mm thick steel plate and I feel that there are going to have to be some serious Hookes Law calculations to get the suspension right!

The next shot shows the components for the "spine" which carries the motors, gearing, and Quill drive for the drive axles.

See Picture 57.

Starting from the top again. There are the two plates that are going to have to be drilled and then bored to take the sleeve for the quill drive with the associated gearing. The next piece is an outer part of the spine, the inner piece, and the other outer piece. The two shorter pieces at the other ends of the inner piece are the tabs that will graft the spine to the sides of the chassis rails, (and transfers all the drive force to the loco!)

I am half way through finishing the last of the 6 driving wheels and the next step will be to cut the 8 bogie wheels. And it the bogie wheels that I am starting to wonder about... In the classical manner they should have the axle fixed between them, however, what I am thinking of doing is fixing the axles and then mounting the wheels on double ball bearing races. This "should" give the loco improved cornering ability. I do know that this was tried on the Midland and the NER itself tried something similar. The chief advantage of this is that the fixed axle can be thicker at the horn block in the horn guides and it will not be subject to rotational wear. The main minus point is increased wheel wobble as the bearings wear...

The flanged bearings that I am looking at are from "Technobots" who will allow you to download their 50 page catalogue. I recommend that you do so if you are serious about modelling large locos -as I have found things in it that are VERY useful!!! I intend to mount the bearing race on the main 6mm thick axle shaft and then turn down the end journals to 4mm. This will mean boring a 10mm hole into the centre of the wheel and having a ball race at each side -thus the wheel should "float" between the two races.

At the end of a very active Sunday -I am in the position to state that I now have SIX snowflake wheels. I will admit that only one of them has anything resembling a flange and tread on it -but that can come later!!! As there seems to be a "dearth" of the type of attachment that I need to make the flanges and coning to the proper Gauge '3' profile I have decided to cheat and adopt the "Colonial" flat tyre and axe edge flange. This shape was originally developed for poor trackwork, it would cut straight through branches or animal carcasses left on the line. Not that I hasten to add would there be any on my trackwork!!! This means that the next item to buy for my lathe will be a face plate. Then I will have to "face off" the front and rear of the snowflake wheel and then align bore each pair (oh boy is that ever going to be fun...) I have bought the much needed metric tap and die set for the smaller sizes, (I confess that I did not know that there was a 0.5mm taps and dies before I bought this). All I hope that I will need are the basic 2.5mm and 3mm taps for the connection of the spring cups etc for the Quill drive...

The forks from the spring cups will have 3mm holes drilled though the main spoke at the the point where the trident forms/ splits. These will connect to the 25mm long 3mm bolts that are tapped into the Hostaform "Bull Gear".

Having fed myself my evening meal I had better explain how I intend to "face off" and align bore my snowflake wheels. This will involve clamping the wheel rim to the face plate and then running a cutter across the spokes until I have a nice flat face. Turn over the wheel and then repeat. Now, the main problem is -is that the wheel is only "true" to itself... What now needs to be done is to make them "true" to the lathe, (and thus hopefully to each other!) Each hub has been bored to 7mm. I now have to "align bore" the hub to 9mm and then sleeve down to 7.5mm with a length of brass tube and then hone it to 8mm. The result of all this madness is that I will have a bore for my axle that is EXACTLY 90 degrees to the wheel rim. I can then "tidy up" the hub to square on the face plate. The next step is cut the tread and leave the flange to be cut to the Colonial profile. I suppose I had really better explain what this is. In a std profile the flange is a smooth taper from the root to the tip. In the Colonial profile the flange is a constant width until right at the end when the there is a 45 degree "axe" edge. The one thing that worries me is the amount of "picking" that the axe edge might do to "frogs" and "wing rails" -as the flange is far thicker than would be normal for most of its depth.

While the "exchequer" saves up for a face plate, I do have 8 bogie wheels to cut. I am going to simply drill a 8mm hole in the centre of my "blank" and then nut up an M8 Allen bolt. This will give me a blank that I can spin and use to mark out my circle with a cutter on the lathe, no more fussing with 4 jaw, (for now...) Then it will be a quick kiss with the angle grinder -some fettling with the grindstone and spin!!!

The end of another evening work in the cold shed has produced the following. All of the 6cm sq blanks have been drilled to 8mm (this was the biggest bolt that I could find!) -just 2mm shy of the 10mm required for the bearing flanges. Here is a shot of the blank clamped on the drill press. The hole has been pilot drilled to 3mm, then opened out to 7mm, and here is the final pass -of the final piece.

See Picture 59.

The following shot shows the blank , plus big bolt(!) clamped in the 3 jaw of the lathe. What it shows is the tool being used as a pair of compasses and scoring a rough line on the blank. This gives me something to aim for with the angle grinder...

See Picture 60.

Last weekend was The Burton upon Trent Beer Festival and as I have always said -the British do business in the Pub... The results from "The Beer Festival Planning Session" are rather good -I am pleased to say, But I would be the first to admit that the constructional drawings now smell of: Ale, Cheese & Onion crisps, and Chicken Tikka Masala... The design of "the spine" that carries the three Quill drives has met with "calculated"(!) approval -although there were some voiced thoughts on: "Perhaps it really should have more roller rather than ball races". The main problem I seem to be facing is getting my Snowflake wheels balanced -otherwise they will want to "hop" in their garland of drive springs and cause unwanted bashing of the tube axle holding the Bull gear!!!

The solution is; either to dynamically balance the Snowflake with drilling and inserting weights -OR (the method I favour) alter the tensions on the drive springs so the wheel doesn't want to move and is forced to sit centrally. The first method requires putting the Snowflake wheel on an axle between two rulers and watching where it wants to "rest" (and then drill a bit of the heavy part of the tyre away). The second entails tightening/loosening parts of the spring compressor until the wheel "floats" centrally. The first method is probably the more correct, but with the second method, (although more fiddly) -means I can fine tune my Quill drive to the loco.

From the "design" point of view I am just using simple Hookes Law calculations to produce the spring specification that I require. Well in fact the spring rating is the average of the three positions that the spring will be in as it moves in relation to the Bull Gear and the Snowflake wheel i.e. static, driving, and braking.

All this has been made harder by the fact that my son has wiped all the pre-programmed equations from my hand calculator and I am having to do it via spreadsheet...

Another Sunday Afternoon and the clocks have changed... (It is now BST) .One thing that has been troubling me, (and I think perhaps it is starting to get urgent), is just how do I assemble my bull gear??? I intend to run it inside a 25mm internal dia needle bearing using a 24mm diameter pipe. Now the question is; do I bond the two halves of the bull gear inside the bearing -or do I drill and bolt the two halves together(?) The safest method is to drill and bolt -but this is also the most difficult as it will entail drilling 2mm longitudinal holes through the boss of the gear wheel and then bolting the two halves together. It does mean though -that I can take it apart... I think it might be a good idea to tap the holes for the 3mm bolts that will transfer the torque from the bull gear to the snowflake wheel. I still intend to nut them tight -but it will allow me to forget any "wobble" on them due to the nuts loosening over time. Currently my lathe is U/S due to a duff ESC board. So, the next phase of the chassis building has been forced upon me due to the fact that I cannot turn any wheels!!!

I have unshipped the board and I am awaiting Chester Tools service dept to get it fixed!!!

During the wait I have been turning my attention to the lights and their connections. The strange red/white dual LEDs have arrived from Texas and I am chopping up lengths of "heat shrink" to make sealed connections with. Once threaded onto the wires they will be greeted by my teenage 25Watt Weller soldering iron -which despite its age is far better than the modern electronic Antex that seems to spend most of its time getting hot....

Tomorrow my friend from "The Welding Institute' is coming around to help me decide how best to begin assembly of my chassis parts. I know that my welding is anything but pretty -but it is strong and I am very good with an angle grinder(!) So, what is the next thing on my shopping list? The answer is the Bull Gears and the spring assemblies. I think that the best way to build the mounts for the Bull gears is to line up all the plates that will hold the Bearings for the Bull Gear and then to "bore out" with my boring bar to 32mm. I then plan to slice the bored plate in two and then weld a hinged clamp fitting to the two halves. This will clamp onto the outer surface of the ball race that supports the Bull Gear.

After some "inspired" madness I have finally decided on the structure of the Bull Gear... This will consist of two Main gears with four 3mm threaded holes through the boss of the gear. This will sit inside a length of 22mm copper heating pipe and then this sits inside a "turned down" length of 22mm pipe joiner. This gives me an external diameter of 25mm(!) The ball races are then fitted and the other Main Gear fitted and then bolted up tight with 3mm bolts.

The next few evening will be spent painting BSM with "blue" and scribing lines on it!!! I am not too good with a hacksaw and blades seem to break at a great rate...

Sunday Evening. Well today and yesterday have been spent wrangling with wires... I hold fast to the saying that any wire cut to exact length is 1cm too short!!! My speed control system (as such) is based on a circuit from the book "Model Railway Electronics" by Roger Amos (I have the 2nd Edition). However I have adapted his "PWayMan Circuit" to my own ends. His circuit uses the 50Hz half wave rectified DC from the mains as his sine wave to "chop" rather than chopping a square wave -this gives Pulse Width Amplitude Modulation. I on the other hand produce my own sine wave -and thus a variable frequency. What I do is use the same Potentiometer shaft (a double gang) to alter the Mark Space Ratio of the "chop" whilst at the same time increasing the frequency. A little soldering / fiddling with a collection of fixed value resistors in series and I can tune the MSR to the frequency. (Lower frequency = more torque. Higher frequency = better battery life)

What I am about to say now I cannot prove -however I do know it to be valid!!!

For some reason a 5 pole motor is the lowest number of poles that you can successfully use a PWAM system with for smoothness. If you try a 3 pole motor -you would be better to just use a simple supply. If someone could like to come up with the reason -then I would be delighted to know(?)

How my control system works is this: Each motor has its controller capable of 3 Amperes each -fed from a 12 Volt source. They share a common connection to the dual gang potentiometer that alters the MSR and frequency. The change of direction is controlled by a Solid State Relay (apply a ground to pin 7!)

The control interlocks are not even at the "scribbles and doodles" stage -so at this time it would be possible to make the system flip from Full Fwd to Full Rev. What has got to be done is to ensure that the system waits until the frequency of the PWAM drops to Zero -before it starts to ramp it up again.

Time for mental diversion, (i.e. a trip to the Pub) -while the subconcious works it all out!!!

Well it did seem to do the trick. I am now home and I know exactly how to get it to work. But in the meantime I suppose I should explain something about PWAM...

The top graph shows a "classic" PWM system using square waves. What I do is to mix in a sine wave from an oscillator and yes all the time pulses are multiples of 1-10 millisecond using a 10K linear potentiometer!!!

Well after a hard day at the desktop.... I have had to ship my lathe back for repairs -something is wildly amiss and I cannot work out what(!) This has left me nothing to do but sort through my collection of "primitives" to turn into functioning parts of my chassis. So, I looked at them took a deep breath and dived into the two chassis rails. The first thing was to make them "true" to themselves. I wrapped a length of parcel tape around one end and drew a square line with the try square at the other. Deep breath, thumb at the side and started to saw - and then broke the blade... Three blades later and I had four square ends. The next job is to make a matched pair of them. I duly clamped with my "moles" and marked out two holes and drilled through both pieces. After having grunted up two 3mm nuts and bolts through the holes, (this is normally enough to lock the two plates in place), I set out marking up the frame plates for the horns.

See Picture 62.

You should be able to see the row of 3mm drill holes that form the top of each guide slot. The two holes either side of the central slot are for the 5mm transverse bolts that couple the chassis frame plates to the "spine" holding the motors and Quill drives. The theory is that simply undoing the 4 bolts will allow me to work on the system as it "should" simply drop out.

Always design your model to be easy to do repair work on!!!

Once the basic cutting of the frame plates is done it will be on to the more "artistic" curves of the bogie plates will have to be done. I am still not too sure how my home made stencil plate will function in practice. It is made from ABS sheet with graph paper stuck to it. I have drawn out the shapes required and then the idea is to transfer them to the steel by simply tracing around them. The curves are going to have to be "chain drilled" to get them right and the spiky plate then ground to shape.

Friday evening.Well for some reason things have progressed at "Warp Speed". I was expecting to be in this position late Sunday evening -but apart from some fettling with the grind stone I have two chassis frames. The ABS template seemed to work fine and the shape of the bogie space can clearly be seen in the chain of holes...

See Picture 63.

After some "inspired work with a hacksaw" the holes are linked together. I have bolted the two frames together with garden bolts to show how they will look. Tomorrow I will present them to the grind stone and then file them smooth.

See Picture 64.

The next step is the bogie mounting plates with their slots...

Well at the end of another Sunday I have drilled and milled the bogie mounting plates. I have to admit that after all the milling required to get the tyres for the driving wheels done it was with some anticipated boredom that I began the days work... However in just a couple of hours (plus tea break) I have my partially finished plates. I am not sure at the moment whether the V slots in them for cable access are now needed, as the cable that I have been using hasn't required much "conduiting" around the parts already installed.

Here you can see the plates and the frames "Blu Tacked" together to see how they will look. Quite a lot of "fun and games" was had trying to get a grindstone around the inside curve of a piece of metal that was FAR too long to move around in my workshop!!! After that I simply gave up and filed it with a half round...

See Picture 65.

The next step is to start cutting the bogies from the Primitives, and that is not going to be very nice to handle!!! The same technique -but in reverse is going to have to be used for the humps of the bogie frames. This will leave me holding a, "designer cactus", whilst I grind off the spikes from the chain drilling. I am surprised at how fast the parts are coming from the stack of Primitives. Once I have a stack of parts it is then out with the welding plant and then 80 Amps with a 2mm rod to weld everything together. I use ESAB Mildtrode which I find to be easy to weld with -in any position.

Sunday Evening, having just showered from a heavy session in my shed -I have to admit that things are moving on at a real pace now!!! I have drilled and matched the bogie arm from the Bogie mounting plate to the mousetrap arm. The Bogie saddles have been drilled. And despite gritted teeth the bogie sides have all been chain drilled, ground and await a suitable slot, (ha ha), in my home schedule for the milling machine to work on them. The Spine is drilled but not yet sawn to size. I would say that 95% of the steel cutting is complete...

See Picture 66.

Now that the majority of the steel has been cut and brutalised to shape -the next stage of the operations will devolve to making the hornblocks and guides. These will be made in the standard 3 layer sandwich method and then silver soldered. Another aspect to be considered over the coming week are the jigs that I will have to build in order to assemble the various parts. These will have to cut from plywood and lengths of scrap pine.

Now the fun begins.... This is "the spine" -the main motor mounts for the loco. On this will sit the three gear boxes and the quill drive. The spine is made fro the three sections of 3mm steel in the picture above. On this sit three pieces of 20mm sq U channel made from aluminium. On each end of the spine are silver soldered two vertical M6 bolts and underneath it two stubs of M6 threaded bar. Six M3 bolts are silver soldered through the spine plates to hold the aluminium channel.

See Picture 67.

On the underside is the "secret".... The spine is actually an articulated mount and when the spine meets a curve it moves and compensates for the angles. Thus the wheels meet the curve flat on. In the shot below the big gear wheel (75mm across) is actually the gear wheel that will form the "Bull Gear" to the Quill drive.

See Picture 68.

I had to try something... I am glad to say that it has worked!!! One of the main problems that I have had is "How DO I fix the wheels to the axles???" The classical method of cutting a slot and ramming a tapered "key" into it only really works when you can "get at" the wheel axle interface... So, armed with my latest toy (I have finally got a compound slide -I have only been waiting 5 months for it....) I cut a 20 Degree taper on the central hub of each wheel. Then having done so I then clamped the wheel in a rotary table and elevated it to 70 Degrees. Now the taper on the hub was parallel to the bench(!) Delicate work with a 1mm then 2.5mm drill in a pillar drill (I broke three 1mm drills...) gave me an inclined hole. This hole I intend to tap to M3 -once I can find/ beg/ steal/ borrow a long Tee tap. All the Bar taps I have will turn the tap ONCE and then the arms clash with the wheel rim...

Anyway, once I have an M3 tapped hole I can then screw in an M3 allen grub screw -this will crush the brass tube on the inside of the wheel hub and thus grip the axle very firmly.

Today was the Spring Bank Holiday -and of course it teemed it down with rain.... This gave me the perfect excuse to do nothing except drink tea and play on my shed. I had been planning to flange the driving wheels for some time -so, armed with the crib sheets from The Gauge '3' Society I duly sat down with; my lathe, the face plate, and a collection of studs, washers, stretchers, (et al). Not surprisingly it was a pig to fit the driver to the face plate!!! The allen bolts that would fit were either too long -or too short, the suds were too wide for the spaces between the tridents and when I thought I had a good arrangement I found I couldn't get the cutter to the wheel. In the end I simply ground a set of allen bolts to the right length and then turned them down so they sat clear of the traverse.

See Picture 69.

I had decided to give my loco "Colonial Wheels" for the drivers. This may annoy a lot of people, (such as my late father), but I do think that they are better for the drivers on this loco as the thicker flanges are more robust. However I will give the bogie wheels tapered flanges and coning as per normal. I will have to make a mandrel for the bogie wheels as I have destroyed the nut and bolt that I used to make them. To be fair I only expected to be able to make one or two wheels from it -and in the end it lasted for all eight.

A few people have asked "I have read the bit above but I still don't understand about a Colonial Wheel?" So I suppose I had better start at the beginning. For large locos to get around tight curves the flanges of some of the driving wheels were absent, i.e. the wheel was flat. This enabled it to slide across the rail. A Colonial Wheel is a flat wheel with a flat flange.

Colonial track was very "rough and ready" and the axe edge profile enabled it to slice through branches (or bones) of things on the track. The idea was the thick flange was harder to de-rail. It has been tried on several "English" railways...

This is a very out of focus shot of two of the driver wheels on the track. When this was taken I had been to retinopathy and you are fortunate that I could focus enough to even get the wheels in the shot!!!

See Picture 71.

Well at the end of an evenings work I have finished the last of the driver wheels and cut the first of the bogie wheels. Cutting the rough into the wheel tread and flange has now become "routine" -however this was my first attempt at cutting coning (that bit was easy) and cutting tapered flanges (that bit was vile!!!) There was no easy way to get the cutter into the piece without the compound slide fouling some point of the chuck. So aided with a 10cm long M10 bolt I moved the piece away from the chuck -but now of course -it wobbled.... I begged a travelling steady from a friend and (at last) I finished cutting my first bogie wheel. One down -seven to go.

Well after several evening of extreme metal dandruff... My late father often said "you have to go into some bad houses before you know you are home" and I always knew exactly what he meant. I have started on my bogie wheels (I have done three out of the eight). However this was not done without the development of a complete new dictionary of "words" to explain my exasperation at certain things. One of the things I have are "indexable replacement tip" lathe tools, this means when they go blunt it is a two minute job with a torx driver to turn the tip round and then carry on. And this is what I have been happily doing! But, they are not as "long" as the old tool steel tools...

But in the end things prevailed and I am now cutting my treads and flanges easily. (I don't know whether the threat to take the whole lot out into the garden and smash it to shards with a sledge hammer helped -but it did seem to co-operate after that).

Another successful afternoon in the shed. All the Bogie wheels are now cut, and I have been assembling my horn blocks and guides. I don't use the technique on milling a slot in a block of brass -what I use is normally referred to as "the sandwich method". I have had my mill and lathe less than a year so I am still learning on them. However I can make sandwiches with the best of them.

The sandwich method uses three sheets of brass, two wider sections and a smaller inner section. Torch the ends with some silver solder and it never comes apart...

The hornblocks are finished and the semi-decorative axle boxes are fitted to them, (they may be made of aluminium channel and Plastikard -but do hold grease).

I have begun assembly of the various modules that will lock together to complete the model. I knew right from the start that this was going to be one of those where it "all came together" right at the end -but the end is still some months away! I have cut and made the grease boxes for the bogie axles to run in. These are as I have said simply off cuts of aluminium channel. The bogie axles do not actually rotate the wheels sit on double ball bearings and are thus free to rotate independent of the axle. I am going to have a go at building leaf springs for it, these will probably turn out to be more decorative than functional -so I will "graft" a torsion bar to the back of the axle.

The spine has been test fitted to the chassis rails. This is held in position via four transverse bolts to a "union" (another piece of aluminium channel) which holds the vertical bolts from the spine. The union has ground down square nuts bonded to the sides -while the vertical bolts are held in place by the compression of the lateral threads. There will be a nut and washer providing the final vertical security and "fine tuning" to the position of the spine. Once that is in place it will get pumped full of epoxy putty and thus will give me a rigid mount.

I now have one set of bogie axles(!) After suitable persuasion with a "cloth and hide", I had a length of 6mm steel bar that was straight. I duly chopped it up with a hacksaw and squared off the ends in the lathe. These axles do not rotate, but simply act as the carriers for the wheels -which sit in a double ball race.

However turning down the ends to 4mm for the first 10mm each side was good practice for the main event -the driver axles.

Well now that I have axles with journals on them I suppose I had better explain the process of making a grease box. This is based, (of course!), on Rhodesia Railways practice... I seal up the bottom of the Aluminium channel with some balsa then using a cotton bud mix up up some 2 hour epoxy and swab the entire inside of the thing with it. This gives me a "tanked" seal. Into the chamber thus formed I cut some felt into ribbons and dollop Castrol LM onto it. A small amount of "Milliput" seals the top of the grease box. In the morning after, "a night on the cooker", it is rock hard, and the grease has now been sopped up by the felt. The Milliput can now be ground flat and drilled for the spring mount.

I have drilled and fitted the horn stops for the bogie sides and I now have to fabricate the "leaf springs" that will disguise the coil spring hidden within them. I will admit that I have never been very good at this and on my first G3 loco I simply gave up after having broken three in a row trying to make them out of lengths of ABS. This time I will use an L shaped section of brass strip with lengths of brass rod down to the 3mm loop connectors that fix the horn stops in position. The coil spring will sit between that and the top of the grease box and the false leaf spring will sit in front of it.

(This Time It Is Going To Work)....

Well the Bank Holiday weekend is here! and in the glorious spring sunshine -I have spent most of it in the shed... However while the rest of the family were "slipping, slopping and slapping" as the saying goes, I was torching away merrily. I have in the past two days used nearly 3 lengths of silver solder and lost my "cool" in the heat of the forge. The first thing that I set out to solder together was the bogie "saddles" as these are really the most important things in the construction of the loco (honestly!). The lateral piece of angle iron was duly bolted to the piece of 3mm plate and the torch lit. The main problem with this piece was that the only real way that it wanted to "sit" was upside down. So I clamped it in the vice and cooked it and its companion. Once they had been cooled and pickled, it was out with the wire brush and on to the next stage. This involved soldering square nuts to the corners of the angle iron . So after having polished up the nut and the area of angle iron that it would sit on -it was again out with the torch. I had to use a lower melting point solder for the nuts because if I had used the same temperature as the solder -it would have come apart... At the end of two hours of work I had two saddles that were clean enough to pose for a photo. The saddles are held to the sides of the bogie frames by M6 Allen bolts

See Picture 73.

The frames were the next victim of the torch... I had planned how I was going to do this some time ago -but as the saying goes "no plan survives first contact with the enemy". I had designed in the slots were the L shaped clamps would bolt through and then G clamps would hold the frame fast to the piece of firebrick. Well after some bench work -I had to move EVERYTHING off my work bench in order to have enough room for the frames, I did solder the joint. However you can tell where the "nose" of the G cramp was -there is a definite "dab" mark!!! I did both ends then hit the next snag. Although the designed in slots had worked well I now had to hold one frame side 9cm in the fresh air while I soldered one end and then the other. This was done by a carefully sawn piece of 3x3 screwed through the slots. and I am very relieved to say that it worked perfectly.

See Picture 74.

In the previous shot You can see that the two "trays" that hold the batteries and associated electro mechanicals have been bolted on through the slots. The L/H tray contains the power control side of the loco while the R/H has the lights and direction control system. (Note the large relay marked STOP). You may just make out the stub of the bogie arm poking out from the rear of the tray. The arm is fixed at this point and moves across the bogie between the main chassis frames. It is the movement of this arm that will squeeze the Quantum Tunnelling Composite and thus tell the loco that the front bogie has begun to turn into a curve. This will lower the resistance of the QTC and thus allow enough current through the relay to close it -powering up the solenoid to lift the mousetrap bar.

I am beginning to hate springs... I had worked out all the Trig and the Hookes Law calculations so the the springs sat perfectly in their stretched length and the forces on them were all correct. Then the manufacturer decides that they are not going to make any more of this value... Thus I have SOME of the springs that I need for the loco -the others I am going to have to scour the web for. Anyway I have enough of the correct value to "float" the bogie arm and bogie (minus wheels) in 3 Space. Thus only the weight of the wheels holds the bogies onto the track -the rest of the weight of the loco is available for traction. The flanges on the bogie wheels will pull the frame across thus transferring some sideways torque to the chassis frames. This SHOULD force the central driver axle away from the centre of the curve thus angling to two outer axles towards the centre of the curve.

Here you see the bogie arm suspended in 3 Space by the four tensile springs. The mounting point for the connecting point is not central as when the arm moves across in its arc the line between two sets of opposing springs becomes straight and they then provide no real effort anymore. The offset from the "true" is such that the steering effect of the bogie will only be effective in curves of greater radius than 1.50m ( roughly 5 feet).

The next step is to order the ball and roller races to fit into the gearbox and the axle boxes. (This could be fun!)

It wasn't fun -it turned out to be one almighty slog of boring waiting.... Over four weeks have passed since I ordered my parts and only two days ago the first of them started to arrive. I know the I am on the final push to complete something when I tick off the days for my orders to arrive(!) Anyway, the first instalment of gears has arrived with some of the ball races for the gearbox, and all six of the 25mm bore needle rollers for the bull gears. So, I now have three sets of nylon reduction gears in a fetching shade of red -which will have to rubbed down and painted black. The same thing will have to be done to main power gears -except they are white!!!

The next set of gears and bearings are for the bull gear and the bogies.

One of the things I am still unsure of is what to make my gearbox faces out of. I would like to use Aluminium for lightness and ease of machining -but is it too flexible in the thicknesses that I can get it?. Brass would make a lot of the work quite easy, as well as looking nice -but the price is really quite high. Steel is comparatively dirt cheap -but it would be the hardest to work...

The shot below shows the arrangement of the gears.

The motor is above (obviously!)
Step one is 20:40 -this clears the side of the motor and forms the input shaft to the gearbox proper.
Step two is 10:30 -the 30 gear providing a central drive to the two 16 tooth gears at each end of the shaft.
Step three is 16:100 -the 100 tooth gear is of course the Bull Gear..

See Picture 76.

The motor that I originally intended to use was the MFA RE-540/1. This is a 3 pole motor with a range of 4.5V to 15V and would have done perfectly well in this situation. However I had the chance to look at a Johnson MM543M. This is a rather more powerful 3 pole motor with a slightly smaller operating voltage range of 6V to 12V. The best thing about this motor for this situation is that it has an inbuilt fan and thus force cools the rotor. It is of "slightly" higher diameter (36mm as compared to 28mm) and thus the torque is higher at lower speeds -but the top speed of the loco would be lower. This is to my mind a very acceptable trade off. I am going to have to re-draught my design for the gearbox as the motor is going to have to straddle the spine -rather than bolt through the screw holes into one side of the gearbox. The motor clamp will have to resemble a large "jubilee" clip and hold the motor between the sides of the gearbox. I am going to have to build some ducting to get the air from the motors to blast downwards from the side facing exhaust ports on the motor.

I have been busy with my brushes -as there is nothing I can do at the moment but wait for parts....

The best thing about enamel is that you can use it in the evening and by morning -it will have set. I normally use Hammerite (in this case Smoothrite!) for my metal work. I am now in the position that all of my chassis components are now painted with two coats -and three where it will take the most "hammer"... Not unnaturally they don't make the correct colour -so it was out with the teaspoons and the mustard jar. I got a nice "Buckingham Green" colour with 4 parts green to 5 parts black.

The shot below shows the chassis with the two bogie side plates and the connecting saddle. The "spine" can be seen bent to its limits, (for illustration), in the centre of the chassis frames.

See Picture 77.

This is the chassis inverted. Clearly visible is the differential connection to the two arms of the spine. Also visible are the three sections of U channel that will form the mounts for the three gearboxes. The spine transmits the thrust through the two 8mm bolts that it is suspended from to the four 6mm bolts with captive nuts that pass through the two sides of the chassis rails. The bogie axle boxes with their "sandwich" horn blocks are easy to see in this shot.

See Picture 78.

The shot below is perhaps the most interesting, (for me). I like for some reason to have my buffer beams made of wood (this one is a piece of Oroko) and as normal the buffers are sprung. It was suggested on the Gauge 3 forum that the draw hook should be sprung as well -so I tried it... I have to admit that I like the effect. My test traction piece, (a tin of nails and a length of string), did seem to want to move more easily with the sprung hook -so I think that this is method that I will employ for this and future locos.

See Picture 79.

The buffers are from Cambrian Models and the "3 link" is from Brandbright, The spring is from a Biro and the bar holding it to the draw hook is 2mm bolt with a couple of 2mm nuts CA'ed to it. I haven't painted the back of the buffer beam because I haven't finished with the gluing. Normally the fixture to the frame sides is epoxied to the buffer beam.

The next problem I have is one of "purity"! Because the loco is going to have to take rather sharp corners I am thinking of going to mount the buffer beams on the bogies -rather than the chassis rails. This will allow the torsional forces on the loco to be reduced when it is cornering and pulling its carriages. There is enough structural rigidity in the chassis to allow this. There is another added bonus to doing it this way as well. When the bogie enters a corner, the side thrust will be transmitted to the frame via the springs centring the bogie -and thus force the spine to bend to the the correct radius.

Well a couple of weeks have passed since the last entry -this has to do with having to tend to my garden... But thanks to severe weather I have been able to spend the odd evening in my shed(!) What I have been slowly building is the "mouse trap" arrangement for the bogies. The patent taken out by Sir Vincent Raven has been applied here -but in a more modest form. The original patent described a longitudinal locking bar that held the rear bogie in place while the front was free to move. This works fine until you have to take the VERY sharp curves that I have... I modified the patent bar into a mousetrap that held a bar that the bogie swung on. This "amplified" the bogie movement into something that I could electrically "measure".

The Quantum Tunnelling Composite (QTC) varies its resistance between 1.0M Ohms to 50 Ohms at 1Kg pressure. There were some rather hysterically funny experiments with the kitchen weights and an AVO meter... This gives me a 6 Volt Relay fed from a 12 Volt source that would not close until 0.3Kg of force was squeezing the QTC. Whether this information would be useful in anyone else's model I have no idea -but you are welcome to use it.

The next shot shows the mouse trap bar closed on the bogie bar (the reed magnet is at end of the bogie bar). The magnet is a commercial one used in door alarms. There are more than few of these left over from my sons "toddler" days...

See Picture 80.

You will notice that I had second thoughts on mounting the buffer beams on the bogie. This is because it simply did not look right and I will live with the fact that it will require a longer length of chain to couple it up!

The next shot shows the bar has lifted and the solenoid is the right of the arm -with the return spring on the left side of the arm. The solenoid is a simple slug type mounted vertically. The slug is tapped for M3 and a length of brass rod has been bent and wrapped around the M3 bolt and secured with a nut. The return spring for the mousetrap arm is on the opposing side to the slug as I found that this gave a more balanced return than springing the slug only.

See Picture 81.

The next step is to wire up the reed that will provide the "earth" connection to the relay. Once the magnet has moved away from the reed the circuit opens, the solenoid drops, and when the bogie arm returns to the straight section of track the mousetrap captures it and the system resets. What I have found that is interesting is the position of the "poles" of the magnet can play such an important part in how fast the reed opens and shuts. The normal position of the reed is "open". By positioning the magnet so that the poles are at 45 degrees to the axis of the reed there is a VERY small "sweet spot" where the field from the magnet is powerful enough to close the reed.

The shot below shows the mousetrap bar and the bogie arm with its magnet CA'ed to it. Above the magnet is the suitably angled reed switch again CA'ed to a off cut of 5mm sq pine. The position of the reed is such that it cuts "off" when the bogie arm is 2mm out side of the gap in the mousetrap bar -thus the solenoid holds the bar "up" while it moves across. The correct distance for this was found by moving a spare magnet over stacked sheets of ABS.

See Picture 82.

Looking at the close up shot... (Remind me to touch up the paintwork when I am finished!) The next thing on the agenda to build is the QTC cramp -early test systems resembled something out of "The Inquisition" -but I think I am finally on the right track. The early designs had it squeeze the QTC only one side. The design idea I am playing with at the moment is a "U" shaped frame that slides across the eccentric with a square of QTC on both sides of the arms of the "U" and thus the QTC is squeezed from both sides. This seems to give a more "repeatable" point of deflection than simply squeezing it from one side only. It is possible the greater area used is "evening out" the resistance to compression factor (?) This should enable me to more accurately position the QTC and gauge the compression required so that it can detect curves great than 13 feet radius. This is the curve rate at which the bogies would have to unlock for cornering.

I don't know how other people do it -but this is how I do it... Armed with a fresh tin of grey cellulose primer and a large expense of newspaper I rattle my tin for 2 minutes and then start puffing greyness over it. It is actually quite a satisfying experience. All the odd off cuts, bits of black or white ABS, balsa, brass steel washers (and the squadron green putty!) et all all disappear leaving a smooth (hopefully) grey shape. This then "cooks" for an hour under a couple of angle poise lamps armed with 60W heat bulbs. After a couple more coats I am happy.

The fitting session went as well as could be expected armed with my Korashu saw and a Dremel grinder I fettled the fit until it all slid on and off beautifully. I had doubts when I first tried a Korashu saw as I had never seen anything like it -it looks a small dagger with teeth. But after a few trials with it I have found it to be almost indispensable for wood work. They are after all used by Japanese wood workers for fine cuts -it leaves an almost "polished" cut.

This is what the grey primer body looks like fitted to the chassis.

See Picture 84.

This is a more "oblique" shot you can (just) see the "moustache" of the air intake vents for the "B" end of the loco -this end held all the electrical switch gear.

See Picture 85.

Only one of the pantographs is functioning at the moment due to a "slight accident" by my son... Replacement parts are on order.

While I wait for more parts I have returned to my soldering iron... What I have found is that the more I have to solder -the harder it is to solder!!! I think I am going to have to make a "custom tip" that is somewhat longer than the Antex screwdriver tip that I am using at the moment. I now have parts of the back of the two modules that are nearly impossible to get to...

Well it has been a little like Christmas here over the past few days... I now have a complete set of gears for my loco and I have been able to try the one thing that I have waited for for over a year -to make a Bull gear!!! I have had the roller race bearing for over a month and the 22 mm plumbing fittings since the new year. I am very happy and relieved to say that everything has gone together perfectly in the first test assembly. (Honestly!)

The assembly procedure goes like this.

Cut a strip of 0.5 mm ABS sheet 10 mm wide and wrap that around the boss of the 100 tooth gear. Lower the pipe fitting over the ABS strip and whack it with a mallet... This ensures a perfect compression fit. Now wrap one layer of PTFE plumbing tape around the 22 mm fitting and slide over the 25 mm internal dia roller race. What you now have is half a tube axle. It moves whizzingly around if given a finger flick -so I don't think that there is that much friction.

See Picture 86.

The next step is to drill the spider holes in the bull gear and tap them to 3 mm. I know that it would be far simpler and quicker to just drill 3 mm holes and double nut the 3 mm bolts -but it stops the torque of the Quill Drive from undoing one side of the double nut. Knowing Murphy's Law -this will be the side that it is hard to get at.

It may be me -but I think this could be the only Quill drive that I ever make...

Well another wonderfully rainy evening means more play time in the shed.

The next two shots show the prototype of the Quill Drive. (My version of it anyway). Rather than use Compressive springs I have opted to use Tensile springs. This has several advantages -not least that I do not have to fabricate 72 sets of spring cups... So, there are six tensile springs from the bull gear to the junctions of the tridents. The tensile springs will help stabilise the snowflake wheel.

See Picture 87.

The snowflake wheel can float vertically +/- 3mm in its tube axle -or swivel +/- 5 degrees.

See Picture 88.

I wrote above that the spine with its articulated backbone flexibility was "just plain weird" after having played with the home brew Quill Drive -it not only makes perfect sense -it is also vital. When the wheel corners the lateral force from the the interior cornering wheel will force the exterior wheel outwards. This will drag the spine across thus restoring the tensile forces on the springs. The reverse will happen when the loco returns to the straight.

Do you ever ask yourself -"Why do I do it that way?" I have a design habit that I use "Switch to Earth" rather than "Switch to Power". As I have written above I am having the problem that I cannot "get at" the solder tags at the back of the 2 end modules. I now have a tag that has 8 Earth connections to it... I am a firm believer in the principle of "Star Earthing", and as you will have gathered -this is how my model is wired. Normally there are just 3 or 4 connections to the Star point -but I have yet to wire in the PWAM or the lights.

The following shot shows the "B" end of the loco with the Yellow cables going to the GND point. To the left of the shot is the lights relay panel and the light code selector switch.

See Picture 89.

I am nearly at the point where I will have to solder in an Earthing Bar to cope with the amount of connections that will be required...

This shot shows the "A" end of the loco with the fuse panel. The motors are individually fused at 3A as is the FAN -the main power fuse is 10A. the small switch to the side is the test switch which provides a duplicate to the switch on the roof of the loco. There is a test probe jammed into the connecting "bus bar" at the end to provide 12V point feed to such things a relays, solenoids (and now lights!)

See Picture 90.

Underneath the fuse panel you can see the start of the wiring for the motors, As per (my) normal I wire the motors in Yellow and Blue cable. The Yellow side has the fuses and the Blue side will connect to the PWAM. Added to this the motors will be "suppressed" and "earthed" -the amount of cables still to installed is reaching ridiculous lengths!!!

I am also becoming rather concerned about the amount of waste heat that will be blown around by the motors when running. Granted that the motors have built in fans and I can stick together some ABS sheet to make some ducting from the exhaust ports of the motors -each motor is going to put 36 Watts of heat into my plastic bodied model. The sum heat is about the same as a set of curling tongs...

Well after another glorious summers day (of rain) and a slight amount of burn creme... I hereby present the world with the wired chassis of my loco!!! Well the control and lights side of it anyway. The lighting loom is connected via D25 plug to the tray and the power control side via a D9 plug. All the wires are taped and loomed as I was taught, tape the bunches of cables in one colour -then the bunches of bunches in another colour etc. All the cables are twisted together -I doubt the shielding effect will be needed -but old habits die hard.

See Picture 91.

The IR "key", (a Velleman module), that will unlock the power side is yet to be installed, (AKA anti small inquisitive fingers device), but the parts for the modulator are in drawer waiting for "iron time". This will sit under the "B" tray with its own coolant fan. I have no objections with small fingers that MUST press switches etc -as an adult I simply make sure that any switch they do throw is safe for all concerned. Therefore I ensure that the roof switches will only be able to run on the ancillories, (motor coolant fans and lights). Small fingers can play with the lights programming switch and the fwd rev switch to make the "ends change".

The next task on the list is to machine up the wheels for the bogies and fit the ball races to them. THEN and only THEN will I be able to test if my maths has worked with respect to the QTC and the unlocking / locking of the bogie arms... I intend to simply lathe in a dish and then fill that with paint then "polish off" the edges to give an Edwardian look. Whether I will drill and mill the holes and slots -I am not sure at the moment(?)

The weekend's work has stopped and I am happy with the progress made -and I finally have a bogie! The shot below shows on the left the painted and sanded wheel with its 2 ball races and one of the collets. On the right is an assembled wheel with its axles (a 6mm dia length of silver steel bar). The whole thing went together quite easily -bar the usual one of sliding the bearings to the right position and using "Green" sleeve retaining compound on them... It is very good stuff -but there are times when I am convinced that I will never be able to get my fingers away from the bearing(!) There is a slight wobble, (< 0.5mm), but this will correct itself when I do "finally assembly" by forcing the bearings into position with a vice -at the moment they are just pressed in by finger power. The bearing have a 1mm flange that takes quite a lot of "squish" to get the compound evenly spread along it.

See Picture 92.

The next shot shows the rough assembled bogie on a length of track. The tempry 2.5mm nuts and bolts have started to be removed and the holes "tapped" for 3mm -typically enough I had just tapped the second hole when the tap broke. Fortunately there was enough shards sticking out for me to latch onto it with a set of "Moles" and unwind it. I set the "back to back" on the wheels with my calipers and then dropped it onto a length of track. You have to give it a push up and down to see how it rolls... I have tried it on my 2 curves, 7.5 feet and 11 feet radius, and it scoots along quite happily. There is no sign of it wanting to "climb the curve" or "hunt" on straights. The fact that the wheels are independent of each other means that it can take tighter corners a lot easier than a solid axle. (It also moves as smooth as silk!!!)

See Picture 93.

The last shot shows the rough assembled bogie in its position under the loco. The damaged finger IS mine -the injury is from passing down my sons' skateboard from its' hook in the wall... Tests with swinging it from lock to lock show that the rims of the wheels clear the arches cleanly. I now have some idea of the "all up" weight of the loco -so I can scour the web for the right spring ratings -but there IS one thing I want to try first...

See Picture 94.

I have a few "test samples" of a type of foam rubber that might make some very nice springs. It is a high density version of the "mattress topper" so beloved of my wife -it absorbs shock rapidly and relaxes gradually over 0.5 seconds per millimetre compression. The original purpose of it is for the transport of computer hard drives -but I think it might have more profitable uses(!)

At last I feel that I am on the homeward stretch with this thing. The experiments are nearly complete and everything is coming together nicely. So, this morning (Friday) I started the main production run. I mounted my rotary table on my mill and nearly lost a thumb nail when it flopped down on me as I was tightening the other end! I centred up the table on the mill with the two ivory inserts, wound some tape around the bottom insert, and press fitted a gear wheel. I calculated the offset for the mill, fitted a 0.25cm drill and selected HIGH on the gearbox. Unfortunately I have a captive dovetail head on my mill which means that I seem to spend most of the time winding it up and down on coarse and fine! (There is a small stub handle for simply bobbing the mill head up and down -but it more "ornamental" than useful).

See Picture 95.

The table was turned 60 degrees between each hole, (the rotary table handle is 40 turns per revolution = lots of winding...) and I have six holes per gear wheel. Each of the holes is going to have to be tapped to M3 -that is 36 tapping operations(!) Hostaform also seemingly "soft" does seem to take the edge off my taps faster than steel. I have found the perfect lubricant for tapping Hostaform -is milk... The next operation on them is to drill out the 1.0cm hole to 1.5cm this is not a hard job -however the only 1.5cm drill I have has morse taper and to fit it into my pillar drill means that I have to remove the chuck and "wang" the drill into the hole. If the drill does not go "wang" then it often falls out... My late fathers advice about releasing chucks from morse taper was "to hit with your shoe" and he was quite right I have found that if I tap it with a cloth and hide the chuck drops cleanly into my hand.

See Picture 96.

The gear is clamped to the bed of the drill with a rubber tipped "Mole clamp". The main problem I have found with working with Hostaform is the fact that is seemingly explodes with a snow of white curls that are statically attracted to the nearest human being... Unlike steel which will eventually rust and wash out of your clothes, Hostaform remains brilliant white and the edges of the curls just as sharp.

This shows the centre of the gear being "opened out" with a boring bar to the seemingly unlikely, but critical, measurement of 2.6cm -this is the diameter of the copper water pipe connector. The centre of the Bull Gear is then a "press fit" (with Blue sleeve retaining compound) to the copper connector.

See Picture 97.

The main roller bearings sit in wooden pillows -these were cut from ordinary Deal soft wood, (it was nearest!). If I had decided to machine the pillows then I would have used something like Meranti or Oroko -but I need something that I could twiddle and tweak to a perfect fit with a craft knife and a bit if emery cloth.

See Picture 98.

The ends were then marked and chiselled to fit into the U shaped holders that had previously been fitted to the "spine". I confess that this the first time I have had to use "Tenon Cutting Techniques" since Grammar school.

See Picture 99.

The 3.2cm holes for the roller bearing where then marked out and cut with a hole saw. The pillow is quite firmly held in a G cramp -as the torque is really quite high... After having donned the eye shields and cramped up the piece and held it in my "Riggers Gloves" I was unprepared for the amount of sawdust and shards that flew just everywhere while it cut through the pillow!!!

See Picture 100.

The next shot shows the stages of assembly of the Bull Gear (from Right to Left) The roller race, the Bull Gear with its copper water pipe connector, and finally the Bull Gear with the axle and wheel fed through it. The roller races are CA'ed into position and the pillows epoxied to the Aluminium U sections

See Picture 101.

The snowflake wheels are connected to the Bull Gear via SPRINGS. The wheels are rigidly connected to the axle which "floats" +/- 0.3cm or +/- 5 degrees inside the copper pipe connection. The next stage is to cut and lathe to size the shafts for the gearbox proper. No torque is transmitted via the copper water pipe connector -this simply acts as a location and spacer piece. The output shaft from the gear box which straddles the Bull Gear provides the torque to both sides of the gear.

There is no physical contact between the Bull Gear and the axle shaft other than the tension on the springs, the ends of the axles will be held in roller races in the horn guides of the chassis.

This is Experimental Gearbox number 1.

See Picture 102.

See Picture 103.

It is a simple lash up from bits of Matthew’s "Mecanno" -but it does prove the principle. The motor has a 20 tooth gear feeding the 40 tooth gear into the gearbox.  A 10 tooth gear feeds a 30 tooth gear and finally a pair of 16 tooth Hostaform gears feed the Bull gear.
 
And when I dropped it on top of the Bull gear -the Bull gear goes around and around!!!
 
The "production model" will have ball races holding the gear shafts -I am told that the squeak from the steel on steel is very noticeable... I have decided to use 0.6cm PolyCarbonate sheet to make the gearbox from. It is light, transparent and strong.
 
Six springs go clockwise and on the wheel at the other end of the axle six springs go anti-clockwise. The mid point of the springs is where the axle will "rest". There is enough "slack" in the springs for both forwards and backwards rotation.What I have worried about is that fact that the motor may be a little bit too powerful for the loco. It has been tested by laying the output gears across the bull gear and watching the drivers go around. Even at only 6 Volts they are whizzing merrily around...

The shot below shows the boring of the holes for the drive axle bearings in the horn guides. These were initially drilled to 8mm and then taken out to 15mm

See Picture 104.

The next shot shows the freshly painted (but not for long!) set of driving wheels.

See Picture 105.

The next shot shows the chassis fitted with the spine assembly. The 3mm set screws are fouling the chassis -s it does not sit square.

See Picture 106.

A few days have passed and the following shot shows that the ball races for the axles have been fitted... This involved taking "just a polish" off with the lathe on the ends off the axles to get the ball races to slide where they should go -otherwise I would have had to pound them with a drift. The cross bar connection pieces have been fitted and positioned by the awful method of filing them to size...

See Picture 107.

The next job is to fabricate the axle boxes and the spring assemblies for the axles. The central axle is going to have to be very heavily sprung and the ones either side of it less so. The springing should go 5%, 5%, 25%, 30%, 25%, 5%, 5%. It is going to be an interesting weekend!

I have been experimenting with the sponge rubber that I have -this is the stuff that is used to pack hard drives during transit. It is wonderful... I can "define" a spring simply by the thickness of the sponge and it is reasonably easy to cut -although I am told that cutting it causes the most horrible squeaking sound.

Well the proof of the pudding is in the eating -as they say. All the maths that was used to calculate the spine, the curves and the colonial wheels would come to nothing if the loco stubbonly refused to take the curves of my (proposed) layout. I do know that there have been quite a few "polite sceptics" and "raised eyebrows" when I posted my article in the Gauge '3' Magazine...

But, here is the photographic proof that it is possible.

See Picture 108.

And here is the closeup... You will notice small experimental slices of sponge rubber between the tops of the horn guides and the chassis rails, it seems to be quite a "happy" arrangement as far as it goes -the production version will be similar.

See Picture 109.

You will note a 60cm rule with a 2.3cm curvature across it. All the wheels sit comfortably upon it and the loco rolls back and forth -without derailing. Some "finger work" was required to get it to sit on the curve though. I had to manually unlock the front and rear bogie bars and then slide the arms and bogies to the correct angle. Needless to say there were some "words" as the flanges trapped flesh between them and the rails... The "Acid Test" of my maths would be to calculate the articulation required for a Milwaukee Road BiPolar which was 1-B0-D0-D0-B0-1. However I would be the first to admit that this might be impossible to get round a 7 feet 6 inches curve.

I have traction!!! The shot below shows the "production prototype" gearbox.

See Picture 110.

Yes, I know it is made from scraps of ABS sheet and balsa, but the point is -that it actually works... I assembled it from my drawings and simply expected to use it to check for "fit" and then "fettle" the gearbox to shape with a pair of kitchen scissors. However since it was just "junk" I had to see what happened when I applied power. If it tore itself to pieces inside a few seconds -then this was expected. It went around and the loco moved -if somewhat slowly. I knew that it was very free moving, but to be totally honest, I would never have expected 20Kg of loco to be propelled at circa 1cm per second by an almost dead AAA NiMH...

So, what it will be like with two fully charged 6Volt SLAs giving it 4.5Ah at 12Volts could be -electrifying(!) There will be two motors powering it, one either end of the spine. The next step is to machine the gearbox out of the 0.6cm polycarb sheet and screw it together. The tension on the bull gear will be maintained by dynamically mounting the gearbox to the same pivot point as the pillow and then forcing it into contact with tensile springs.

This will enable the gearbox to move with the spine as it flexes and shifts when the loco corners.

As I have stated above I am using 0.6cm thick Polycarbonate sheeting to make the "production gearbox out of. It is possible the most VILEST substance to work with -yet the most rewarding. The sheet is optically clear and has the strength of 2mm thick aluminium -yet it is lighter and far easier to machine. However it is the machining that is the main problem. I initially tried to cut it with a jigsaw and a "metal" blade -it was a nightmare. This is because the friction from the blade caused the small plastic "swarf" to melt and thus stick the blade to the sheet. I then tried a medium cut blade for wood and that worked reasonably well. The best thing was a wet sponge that dripped water all the way along my cut . This not only cooled the blade below the critical melting point of the swarf -but washed away the swarf as well.

After "truing up" the cut pieces with a file -and about 4 strokes was all I got before it clogged up. I eventually used a "Leading" file and then smoothed the faces with a wet pieces of wet and dry abrasive (emery). At this stage the pieces looked almost pretty in their shiny state.

Then I got to work on them...

After a couple of hours marking them out with a ruler and a pin point stylus it was time to assemble the pieces into the gearbox frame. I transferred all the gears from the "experimental" and "prototype" gearboxes to the parts box -prior to building the working ones. When I assembled the parts for the gearbox frame I used "thick" CA -possibly this was a mistake as the gearbox sides rapidly assumed the typical CA "crazing" across the clear parts. I have a few "oil way drills" as I like to call them -the only thing they ever get used for is drilling holes for axles across large distances. I dug out a 0.4cm one and took a deep breath and then bored the four holes that would define the locations of the gear shafts. I delicately fed the shafts through the holes and found that the gears meshed. The next step was the bore out the holes to 0.8cm and fit the ball races that would hold the shafts.

Fitting it all together was I have to admit a complete hassle. Each of the bearings, collets and gearwheels decided that NOW would be the time to fall off the shaft and roll around the shed floor. So, after several mugs of tea, slow and surprisingly delicate work with a mallet all the components were threaded onto the shafts and the shafts twirled for play. There are some places where the gears grate slightly -but this is on the odd tooth and should wear away quite rapidly. The next step was to re-enforce the CA bonded sides by drilling holes and then threading them. Thus I will have a steel pinned frame.

Well a slight re-cap.

First there was experimental gearbox number 1, (made from my son's' Mecanno) -which I though was far too fast with a ratio of 1:37.5. First reduction 20:40 second reduction 10:30 third reduction 16:100.

Then there was production prototype gearbox number 1 -which is far too slow with a ratio of 1:750. First reduction worm and spur 1:30 second reduction 10:40 third reduction 16:100. However this concoction of 60 thou ABS sheet and balsa did actually propel the loco from a pathetic power source -so it might get used later...

This is production gearbox number 1 which I now think is "about right" with a ratio of 1:37.5. First reduction 20:30 second reduction 10:40 third reduction 16:100.

See Picture 111.

Yes the gears are the same as in experimental gearbox number 1 -but they are arranged differently. This is to produce a smoother increase in torque. The gearbox is made from 0.6cm thick polycarbonate and the 0.4cm thick shafts sit in ball races. The gearbox has been coupled to my milling machine and the gears broken in at stepped speeds -the final was 2,000 RPM and there was no apparent distress.

The next shot shows the spine with the quill drives installed into the loco chassis. The two transverse bars transfer power from the spine to the chassis. The two end gearboxes will also mount onto the stubs via a simple L bracket. The 1cm silver steel axle shafts can be seen in their ball races fitted to the horn blocks, (the horn guides are not yet fitted). The central gearbox, (yes I have finally decided to put in three after dithering about the space required), will have to be designed after the two end gearboxes are installed -that way I will know how much room and what shape it has to be!

See Picture 112.

The next shot shows the two gearboxes in their position, (just placed there for the shot), and a motor in the position that it will occupy in relation to the gearbox -simply Blu-Tacked there(!) The motor will drive the gearbox via a 1:1 cog and chain system. The MM534M motor has a stall torque of 1,800 Grammes per Centimetre, (1,765.8 Newton Metres), after the sequence I have found that only one of this type of motor would move the loco, (and it will have three)...

See Picture 113.

When I have finished mucking about with the gearboxes I promise that I will "P" clip the wiring loom back into position. I have no "P" clips of the right size and I refuse to buy a bag of 100 -when I can swap a couple with a friend.

I was asked on a forum how I calculated the final drive ratio and could I explain the maths -please. So I will go through it here.

The final drive ratio of the production one is the same as the experimental one i.e. 1:37.5

This is worked out as follows:

(1 / R) = {(20 / 30) x (10 / 40) x (16 / 100)}

(1 / R) = {0.666 x 0.250 x 0.160}

(1 / R ) = 0.02664

R = 1 / 0.02664

R= 37.54

The next problem is that the Bull Gear is smaller than the Drive Wheel so that the output ratio from the gearbox INCREASES.

This factor is 70:95

Final Drive = 37.54 x ( 70 / 95 )

So the final effective drive ratio from motor to drive wheel is 1:27.37

Henry Greenly recommended a ratio of between 6.5:1 and 8.5:1 for Gauge 3 models. However, his 1920's motors were series wound with field winding as well as armature windings and the armatures were circa 5-7cm across. The modern permanent magnet motor has smaller armatures but can operate at far higher speeds. And to be honest I don't think that Henry Greenly ever contemplated an electric locomotive weighing in at 20Kg. The motor is capable of 16,500 RPM which gives a physical speed of 3.03 Metres per second equates to a scale speed of 151 MPH. Which I think is fast enough as the original was only supposed to do 86 MPH with 16 teaks behind it.

During the day I have been at work and here is the nearly finished gearbox -but I am not happy with it. I think that I need to remove and remake the input shaft to the gearbox. This will entail threading the 4mm input shaft and nutting the sprocket between two nuts. This will give me, (I believe), a better and more robust connection. The motor has been "wound up" to full speed, (i.e 16,500 RPM), with my antique Farnell Lab power pack. Nothing untoward has happened except the Castrol LM grease on the gear wheels was centrifuged off and some flew into the open mouth of my son. Unfortunately I did not have my camera ready -but it was obvious that it did not taste too good...

See Picture 114.

There have been some domestic priorities that have meant that my work shop has been filled with all the stuff that should be in another room -my wife’s summer house. Allied to this I am waiting for the final parts of my order to arrive, and there is an expected postal strike looming... I am awaiting my ESC parts and the PIC chip board that will control it . YES, I have finally admitted defeat and I am going to on-board logic control with R/C.

Well you may ask yourself -so what has he been doing with it -the answer I am ashamed to to say -is not a lot!!! Work in my business is seasonal, I have had domestic priorities to deal with -and then I had to re-build my wife’s summer house...

But while I have not been playing with my locos I have been busy with the speed control system. While doing my researches for the Technical Manual -I stumbled across the american company called "Dimension Engineering". They produce a series of controllers that (quite frankly) were never ever designed to run locos -but they are just perfect for the job. The two that are suitable are the Syren 10 and Syren 25 controllers. They have an on-board CPU and it can be controlled by an external CPU. In the UK they are expensive at £54, when I commented that I liked it, an american colleague commented that; "For $75 it had better be" -then I told him the UK price....

It operates in a number of "modes" from simple variable resistor, (great for testing), to a digital serial input, (great for me!).

See Picture 115.

The device is about 60mm sq (the smaller Syren 10 lacks the big heat sinks).

When everything is finalised I will use a PIC 16 series CPU programmed in the FORTH programming language, (yes I am that type of geek....) But, while I am developing a feeling for what I can do with it I am simply messing about with a BASIC Stamp 2 CPU board. This is a cheap card populated with stuff from e-Bay -I think I spent nearly a fiver on it(?) I think the hardest thing to get was the PP3 battery, (I had to "persuade" my son to let Daddy have the last one from the family stock). The "chip" uses a PIC 16 series with an on board BASIC interpreter -it takes a massive 49 lines of code. (Remember that the Apollo Lunar Lander Computer took 14 lines of code?).

See Picture 116.

The breadboard on the left is about the size of a floppy, the blue socket is for the BASIC Stamp 2 "chip". Hiding behind the PP3 is most important button in the world -the reset!!! Each of the pins from the "chip" has a blocking resistor for "oops!" events -there are 16 of them.

I admit that I am simply playing at the moment!!! I have it raising the pantographs at startup then whistling three times. When the R/C signals fwds; it whistles twice, the lights then change to the correct code, and then the acc loop ramps it up to speed. The R/C signals slow down it dec loop slows it down, (the inertia is used to re-charge the batteries!), it stops, whistles three times. If the R/C signals reverse the lights change ends, it whistles long once. It whistles twice and then it moves off.

It is all absolutely ridiculous, (and I love it)!!!

Despite the fact that blood has been constantly pouring everywhere -I have been busy(!) I gashed the end of my ring finger and it has been very messy for the past two days. I finished painting the base coats of Saxony Green and Gloss Black over the body work.

See Picture 117.

The second pantograph has been repaired after its contact with my sons' Frisbee (don't ask). I have altered the method that I was going to use to hold the pantograph arms aloft. Previously I was going to use my "standard" method of dynamically bending coil springs -but a few high speed tests show that this method is fine for speeds below 1.5m S-1 thereafter it starts skipping.... So. I have gone back to basics and produced a polyharmonic system using three springs. All springs resonate at certain frequencies, thus if you get a spring tensioned to resonate at 5Hz and then tune 2 others to absorb at 5Hz -the result is perfect stability.

See Picture 118.

The last thing to be installed prior to power trials is the Syren25, This is sitting nicely underneath its little cover -where the power resistors would have sat in the original. It too is cooled by a fan drawing air over the fins -as was the original. In fact this little circuit board almost duplicates all the functions of the original system -it also regeneratively brakes the loco.

See Picture 119.

Everything is progressing well and it is on course to doing a quick trip to the test track (up and down the downstairs hallway!)

I was asked about the control electronics on a forum, and this is my reply;

"As to the control electronics -they are ridiculously simple. The Basic Stamp 2 chip has 1 serial input (PIN 2) and 1 serial output line (PIN 1), PIN 5 to PIN 20 are the general I/O lines. The Syren serial digital input is connected to the PIN 5 of the Basic Stamp 2 chip."

The main problem I now have is -where do I put it? Despite the size of the loco there really is very little room in there, and I am beginning to debate whether I can get a place far enough away from all the power electronics to provide a nice noise free location -the alternative is to erect a Faraday cage... Believe it or not a possible location could be under the "A" end battery tray, but that will involve quite a lot of ribbon cable and more than some "fiddling" getting everything in, and out, of position...

Now the serious work begins and the "fun" part is over...

I have The Syren 25 ESC, The Basic Stamp 2, and (finally) The Giant Cod 2.4 Ghz 6 channel R/C unit. Now the main parts have to grafted together and got to function as a whole. The Cod controller seems to be a re-use of classical RF modem equipment and there was some domestic concerns as to what frequency it operated on however non of the domestic equipment has complained... The Rx for the Cod equipment did prove "interesting" to set -but this is not their fault. The Rx is housed in a translucent smoked plastic box the main problem being that the cable indicators; (signal) (+) (-) are cast into the moulding and very hard to read!!! A slight rub with a chinagraph pencil revealed the legends though.

After having wired the plugs for the connection coupled up a battery pack to the Rx -I began.

I personally like to have separate battery supply for a Rx, it is a personal foible based on the noise from the BE connection on most ESC units, which I find to be excessive compared to a pure DC supply. Pushing in the 8 AA batteries to the Tx produced, (after some terminal cleaning), a red light. Step one complete. Turning the power on to the Rx produced -nothing... A quick check of the connections and try again(!) Pushing a (loaned) quilting pin into the central hole at the rear of the Rx unit produced the green light on the Rx unit. This showed "binding" to the Tx unit was established. Step two complete. The next steps involved plugging in a spare servo and wiggling the sticks to find which socket -was which.

A few minutes produced the following "cheat sheet".

Ch 1 l/r on RHS joystick.
Ch 2 u/d on RHS joystick
Ch 3 u/d on LHS joystick
Ch 4 l/r on LHS joystick
Ch 5 (?)
Ch 6 (?)
Ch 7 -is actually the Battery input line(!)

So, the next step is start assembling the digital cable work to make everything happen. I think that I will start off with simple 3 core twisted cable at 2 twists per centimetre -which should "knock out" the 32Khz hum from the ESC. Then I have to isolate the motors from each other, the supply lines and then star earth the shielding to them.

In short -all very boring slog.

Sorry -I forgot to post the pictures....

This shows the Rx unit plugged into the battery with the on/off switch.

See Picture 120.

This is the Tx unit.

See Picture 121.

The next shot shows the initial test lash up. The bright blue LED on the ESC looks like continuous arcing in the roof top hat fitting. This is quite unnerving in a wood and plastic model(!) The ariel from the Rx unit has been placed under the unshielded test motor to try and induce maximum interference with the signal -as yet I have been unable to induce any.... But, I will slog through the wiring procedure, just in case.

See Picture 122.

The twisted strands of the signal lead are plugged into Ch 3 -which is the click stop Left joystick. A little playing with the trim control was needed to get the exact neutral position. The setting that the ESC is currently using is R/C standard in mode 1. The digital (white) cable is connected to S1 on the board and the (-) and (+) lines coupled to the Tx unit. This involves putting DIP 1 DOWN and DIP 2 UP. There are 8 DIPS, 4 types of setting and 17 modes for this ESC...

Am I happy -yes definitely!!!

At the end of a very successful Sunday morning in the kitchen. I have completed the first static tests of my loco Having perched the loco on the ends of two drawers I then began to plug up the fuses in their racks and and the "yank" cable that you pull to kill everything dead. The 6 volt SLA bricks had spent most of the night being charged and I thought I was now ready...

I rigged up a impact zone at either end and connected the battery.

Thankfully nothing happened!!!

Clicking the joystick on the Tx one notch up, produced grumblings from the motors, at two notches they were turning.

See Picture 123.

What I like about this is that the "notching" is very noticeable, and it duplicates the actual method of working. The model will have 14 notches and the real loco had 12. The shot is the best I can get -sorry! I had hoped to get a nice picture with all the wheels and cogs blurred by motion -but the camera is too smart for that....

Now that I know that the system is actually going to perform as expected, I can sit down and work out the suspension -which is going to use wedge shaped strips of sponge rubber. This has the advantage that it naturally damps itself and the stresses are all linear. The rubber that I intend to use is used as the packing material for hard disc drives. Its properties are well documented by the manufacturer concerned and I have a ready to hand supply of used packing pieces...

See Picture 124.

I sent an e-mail to Customer support at Dimension Engineering -I asked them about changing the ramp settings on the Syren 25. But this is apparently impossible. What they did suggest was to use the R/C Mode 2 working which has an exponential setting (DIP 5 DOWN). So, I am going to try this as it might prove to be more useful for slow speed working. This mode accepts "whatever I find on startup is neutral" so it removes the 1500 mS timing as being neutral. This will help, as there have been a couple of occasions when the motor has run from startup -I had not centred the click joystick exactly. This is annoying, (and startling), during testing -but could prove to be a real problem when I am running the loco.

Once am happy with the progress up and down the kitchen floor test track I will begin fitting the ESC and Rx into their permanent positions. This is going to involve moving a few wires and possibly changing the switches on the Top Hat on the roof. At the moment they are simple stalk switches and I think that slide DPDT switches would look less intrusive.

The evenings test on the kitchen floor test track have proved that I REALLY do have to sort out the suspension... I didn't mind the wheel slip, that was expected, but rather the wheels hopping and bopping to the quill drive as it tried to centre the wheel. What I intend to do is drill each of the sandwiches and install a U top bar. Into this I squish my shaped rubber strip. This then rests against an L frame which hides "the multitude of sins" that is the suspension(!)

A few 2.5mm holes, a few 3mm taps and I reckon I will have something that will work.

I have sat down and designed my suspension system, this will be made from 7mm L shaped sections of brass and 6mm sq sections of brass -all from the local B&Q. Because the sandwichs slide fore and aft while cornering, there has to be a gap between the guide and the sandwich -in this case 5mm. The L sections will be silver soldered together and then "prettified" with by chopping the corners off and rounding them to give a more pleasing design. The re-enforcing angles will be made from offcuts of ABS strip and stuck on when everything is ready

The next step will be to design a drilling jig to produce the pilot holes (2.5mm) for the M3 tap -then the 3mm threaded studs can be "Loctited" into place on the chassis rails.

The more I look at the motors, the more I feel that building a plenum chamber, and ducting the air from the overhead fans directly to the front of the motors -is a good idea. This will also entail building some ducting to direct the exhausted air from the motors to the outside...

It looks like a busy Sunday in the kitchen(!)

Making the horn guides has begun. After the wait for the supplier to get the correct grade of silver solder into stock, (I like J&M Silver Flo55), the building of the "jigs" can begin. These are normally made from off cuts and scraps of balsa and today was no exception. These have been knocked together from 5mm sq pine strip. It is also the first time I have used yellow "Aliphatic" glue -which I am not quite sure that I like... (Next time I think I will wear protective gloves as my skin feels very sore where the splashes of glues have gone?)

Here you can see the brass "L" sections on their jig.

See Picture 125.

The sections are then "CA'ed" to the back of a sacrificial piece of balsa this gives a rigid structure that just has to last long enough in the MAPP gas flame to get the solder to flow along the joint!!! The piece is separated from its jig by some delicate work with two forks...

See Picture 126.

The next step is to assemble a suitable holding device, (probably a small vise), to hold the pieces in place while I hit it with the torch.

Sorry for the delay in getting back to this -but you know how it is...

The pieces of balsa with their L sections of brass strip (a B&Q special) have been used to produce the second of the series of three jigs. This is the one used to align the hornguide for drilling the holes for the chassis side rails. Some polite work with CA produces the jig and this was clamped to the bed of the mill.

See Picture 127.

The procedure is simple -drop the piece in drill the hole and repeat until there are no more pieces, move the drill, etc, etc. This means that although the holes may have a slight offset from square -they ALL have this(!)

The now drilled hornguide, still stuck to its piece of balsa, is then in turn stuck to a piece of scrap steel.

This piece actually was used to produce the tridents for the fabrication of the snowflake wheels. The holes from the hornguide are drilled through. After some tapping to M3 NOW there is a master jig that can be used to produce the hornguides from...

See Picture 128.

This piece actually was used to produce the tridents for the fabrication of the snowflake wheels. The holes from the hornguide are drilled through. After some tapping to M3 NOW there is a master jig that can be used to produce the hornguides from...

See Picture 129.

The last shot shows the reverse of the master jig. The pieces to make the hornguide can be "nutted up" to produce a nice square edge before the torch. The area where the solder will "spit" onto the steel has been well scrubbed with a pencil. Next Step is: Silver Solder, Borax and MAPP gas!!!

After a few scorched nuts and bolts, I have completed the silver soldering of the hornguides. These then got suitably trimmed and filed to shape before meeting the red-oxide primer.... The next shot shows the hornguides bolted to the loco chassis. I am beginning to develop a deep dark hatred of doing things 6 times over....

See Picture 130.

As you can see the paintwork is beginning to arise out of the paint pots(!) There never was any "official" paint work for this loco as it spent most of its time in either Grey Primer or whatever the apprentices at Doncaster had to experiment with at the time in the paint shop. At this point I would say that the engineering and construction of this model is essentially complete and all that remains is the normal frippery of slow modification and detailing of parts.

So I leave you with a photo of the NER EE-1 on its way to the scrap yard... Not as you might expect a sad ending -but rather a victory for it. Even though it was destined to be a one off prototype and never earned a penny in revenue it is still an object of wonder...

See Picture 131.

Addendum:

A few people have asked me where I got the information from for this loco.

The main side view is from: “NER Record Volume 2” by HMRS

The electrical bogie interlocking and patent details are from: “Railway Electric Traction (1922)” by FW.Carter.

The drawings and details of the loco can be found in: “The Electric Locomotives of the North Eastern Railway” by K.Hoole.

Highly detained plans and drawings are available from “Prototype Gas Turbine, Diesel, and Electric Locos” by D.Hulls.