NER EF-1
(well NEaRly...)
This is the first locomotive that I have build that actually came from a magazine article. Admittedly the magazine article is a photostat and it was originally published in 1927.... It has been very interesting to me to get inside the mind of the person who wrote it. He designed this model and (justifiably) won an award for it, and it is, (for 1927), extremely high tech. This is both it's strength and it's weakness. The model could have been produced with, (then), common articles from suppliers. However here at the early part of the 21st Century the suppliers for parts are gone to dust and the (then) technology used in the model power supply can only be classed as "Highly Dangerous"...
The article comes from "The National 2.5 Inch Gauge Society" -and I love it!!! The plans may be found under "Published Designs" , "LNER" , "N.E.Rly. Electric" by R.W.Dunn. No, it is not a de facto prototypically correct model, as it is designed for 3rd rail pickup not pantographs. In fact I would call it a typical model of its era and anyone looking for the correct shape rivits had better forget it. In this time track was what was available and I love the paragraphs in Henry Greenly books on the use of umbrella spines for rail -or lengths of fencing... It is a centre cab design -and anyone who has seen the front of the Henry Greenly book "Electric Locomotives and Railways" will no doubt think that this is the model that is the illustration on the front cover -but it isn't . (Yes I made the same mistake!)
The article is well written -but as was common at that time, the author assumed that you knew what he was talking about, and that the reader had access to a lathe and milling machine, (at the very least!) As readers will know, "Kitchen Sink Engineering", has neither... Suppliers for Gauge 3 parts are not common and frankly sourcing parts is an "if and when" process! Armed with a scaled up (to 13.5mm to the foot) printout I hit the internet to find (well anything really!) Fortunately the scale is 1:22.6 which is very close to the LGB scale of 1:22.5, so by judicious use of "left handed and then shoved in sideways" I did source things that could be used to provide starting points for the model. One thing that is not written anywhere in the article is the scale that they were using then -which was 0.5 inch to the foot. The more modern scale is 13.5 mm to the foot (or if you prefer it 17/32nds to the foot). The dimensions are all Imperial and multiples of 1/32nd of an inch . This was expected and some time was spent with my trusty calculator turning Imperial to Metric, I then had to re-draw the drawing to the new scale and measurements.
Does the resultant mongrel resemble the Imperial plans -yes they do. The motor article is somewhat unusual nowadays as it details how to BUILD it from wrought iron, (there were no such things as "can motors" and NIB magnets then), and as such the model has no pivots for cornering or any form of suspension...
The description for building the bodywork is only a paragraph or so, and the author says to knock it up out of 24 gauge tinplate. I decided to use something rather more robust and used 9mm ply -which I later "plated" with 60 ABS sheeting in my usual manner. The small sheet of graph paper in front of the model shows the "metricated" drawing for the bogie design.
Here it is after plating and a few coats of grey primer. The handrails are from Cambrian Models and are lengths of 1/16th inch brass wire. The projecting 3mm nuts and bolts will hold the pantograph.
As stated above the model has no real suspension despite having working hornblock assemblies -the springs (as such) are made from lengths of 20 gauge steel strip. I decided to make something a little more smoother -and more modern(?) The question mark at the end of the last sentence is due to the fact that the instructions for this type of suspension come from a book printed in 1904... I have some coil springs that I will use on the inside of false leaf springs that move on the outside. First step is to make the horn blocks.. These are simple sandwiches of 64 thous brass sheet cut to produce an H section then silver soldered together. The sandwich is drilled and split to produce the blocks.
These are then cleaned up with wire wool and emery until they are ready and then some file work (and more than a few words) are used to fit them into the slots. They must slide quite freely up and down the slot.
The blocks are held in position, (and only allowed to move vertically), by square sections of K+S brass tube. Here is a shot of the piece of sq section being drilled for 2mm holes.
They have to be positioned VERY accurately. The bogie has to be vertical and the slot along which the block will slide has to be horizontal, finally the axle has to be level through both holes. And YES it is a fiddly as it sounds... Then, and only then, can you drill the holes through the chassis plates and bolt your guide to it. You have to do this 16 times....
The ugly nuts will be hidden behind pieces of ABS shaped to resemble "pukha" horn guides -no one will see them again anyway!
The projecting 5mm bolts in Picture 5 form the mounts for the "leaf springs", These are held in place by a 5mm solder tag and a 2mm nut and bolt. The top of the leaf spring will be held to the top of the grease box (as seen in Picture 6) with a 4mm setscrew. The grease box is simply a sawn off length of aluminium U section.
The next shot shows the suspension componants. The spring is held in place by two washers CA'ed to it. The washer spring combination is then tensioned by a 30mm M4 setscrew and nut and left over night to cure.
The suspension unit will be mounted on an L bracket from the chassis side plate. The head of the setscrew will sit in a hole in the top plate of the grease box and be epoxied into position. The suspension unit will be mounted on an L bracket from the chassis side plate. The head of the setscrew will sit in a hole in the top plate of the grease box and be epoxied into position.
The original locomotive ran off 1,500 Volt overhead lines and had two 750 Volt motors arranged in either series or parallel with resistances to alter voltages. The motors that I am planning on using are 6 Volt 3 Ampere rated. Yes if I follow the instructions in the article I can build a speed controller made from flattened sections of electric heating element -however I have opted for a more modern PWAM controller from MFA. I will couple the motors in series and the batteries in series to provide it with a 12 volt supply that it can modulate to them...
One of my main concerns with building this model has been the sheer mass that has to be moved. In an effort to stop "cold snatch" of the gears and drive chain I have designed a torque absorber or what is in effect a simple "Quill Drive". It is a variant of the "Silent Block" system used by the London Underground.
The initial startup jerk is absorbed by compressing the springs and is later released as the vehicle achieves steady speed. The next shot shows the torque convertor (or quill drive) in place on the test axle -a length of 6mm bar. The black main spur gear and be seen as can (just) the black chain cog bolted to it. At the rear of the main spur gear, the springs to the vanes for the drive take off to the axle can be seen. The main drive worm (in white) pokes up from the motor. As the axle moves up and down in the horn guides the worm maintains contact. The motor has a built in cooling fan and I have had to cut slots in the bottom of the model to enable the hot air to escape...
Having spent most of the time upside down while I poke at the suspension and power train I thought it was time to turn the loco right side up and attend to the roof....
This is a Classical "Henry Greenly" Pantograph, (the design comes from his book "Electric Locomotives and Railway"), however I have modified it for modern sources of supply. The rhombus is made from K&N 3/32nd tube with 1/16th rod ends. These are then soldered to 3mm crimp ring connectors and then held together with 3mm set screws and nuts. The ends of the set screws are pushed and bonded into two sections of 5/32nd tube and one section of square, (at the apex), this will hold the rhombus at the correct spacing while I affix the "horns" and collector "bow". The bottom of the rhombus is held aloft by compression springs bonded to the plate that the base pivot of the rhombus sits on. The arms of the bottom half of the rhombus are simply threaded through the coils.
The pantograph is now shown as it would sit on the loco -as would have been normal for a UK loco of this period both pantographs would have been raised to connect to the 1,500Volt DC overhead wire.
Sorry about the rather "blue" shot... But, here is the completed pantograph.
See Picture 15
The square spacer bar is now removed and the collector horns are in place. The horns are made from 15cm lengths of 1/16 inch tube. The ends have been bent to 45 deg by gripping them in a clothes peg and bending, (honestly!). Then two 3mm solder tags were slid onto each length. 1mm hook up wire was then threaded into the tubes and the assembly bent to a 90 deg angle. A quick dab with solder at the end locks it into that position. The horns were then placed UPSIDE DOWN on the spacer bar and the 3mm solder tags threaded onto the 3mm setscrews and the whole lot tightened up solid. Again a quick dab with solder fixes the solder tags to the tube and the horns unbolted and then re-affixed in the upright position after the spacer bar has been removed. This positions the horns and collector in a raised position relative to the top of the rhombus. The nuts are held in place with dabs of "thread lock" to stop them coming undone...
One more to do!
A few weeks have passed and I have been priming and painting (this model amoungst others!). Here you can see the nearly finished loco with the partially assembled handrails. The bogies are in a typical Edwardian colour -red oxide. The fwd/back and power controls can be seen on the roof just in front of the rear pantograph. Still to be added are the various door knobs handles and hinges etc (and of course -to put the windows in!!!). This is my first Gauge 3 loco and I have to ask my self am I happy with it? The answer is yes, although it has been quite a steep learning curve coming from 16mm to G3, and I was not prepared for the sheer weight of the models and track -I have really enjoyed building this.
