There comes a time in every modellers life when you think "I would like to build that -but how the @@@@ do I do it?" At the moment I am building and accumulating parts for the Gauge 3 section of my (to be built) new railway. For some reason I have decided to build very early electric locomotives of the 20th Century. They are (surprise) very strange to modern accepted practice and I feel fortunate that I do actually have some early text books that detail their method of operation... The early designers had plenty of experience with steam locomotives so they took that TECHNIQUE and applied it to the electric traction. The result was early electric locos resemble (mechanically) steam locos in their operation -but are powered by electricity. THUS there are cranks, jack shafts, scotch conrods, lay shafts, and sundries galore!!!

I have also decided to mangle certain aspects of my locos and they will all have pantographs of the double bow rhombus type. The current build schedule is the NER EF1, the NYC 'S' motor, the NER EE1 and the Pennsylvania Rail Road electric. All of these have their intense problems. I do have a wonderful article from 1927 detailing how to build a (then) very powerful locomotive based on the NER EF1. It is this that I am building at the moment and things are progressing (reasonably) well. However the technology of the period has not stood the test of time, and I have translated all the dimensions, (based on Imperial in 1/64ths of an inch at a scale of 1/24th ), to metric with a scale of 13.5mm to the foot. There are instructions in the article for building a voltage regulator based on resistance wire from electric fires. Allied to this there are series convertors and a liquid based rectifier.

NONE of them I would contemplate building...

So, I have returned to my modern TECHNIQUE rather than modern TECHNOLOGY. A warning for the future of your model is simple -if a fuse blows -you can replace the fuse -if a bridge rectifier goes -you should be able to find something compatible, if your CPU goes -you are stuffed!!! This may sound strange -but it is true. I do know of several CAD CAM systems that lie idle because the chip for the CNC side to control the lathes is not available anymore -and the lathe is only 5 years old!!!

So, a little thought into how you are going to service your model, when it all goes wrong, does not come amiss at the start of the design process. It may be better to use a common 2N3055 with a zener as a stable power source than an all singing dancing (and unobtainable) HEXFET using a NAND gate to drive it, (trust me I have been there!)

So, how does the use of TECHNIQUE-OLOGY define what you can and cannot build? The simple answer is : it doesn't!!! BUT, it will help you decide HOW you go about building it, I define Technique-ology as the science of choosing the correct technique...

Some of the techniques are physical, some of them mathematical, and some of them philosophical.

The physical techniques you should now be aware of -buy having read some of the Kitchen Sink Engineering pages. None of them have used "classical" model engineering methods -not one of them has used a lathe or milling machine. everything has been done via hand tools. This does not mean that I will not use power tools -I did build my sons crib with the aid of a jig saw and power router... BUT I have not found anything better to cut my modelling ply with than a Japanese pull saw called a "Kumagoro", this produces an almost polished cut and for larger pieces I use a "Khugihiki". This is in conjunction with my faithful tenon saw and bow saw!!!

I have not exposed you to the mathematics that I consider to be needed for the calculations for designing a loco (or an item of rolling stock) this is not out of expected fear and loathing -but simply because they can be replicated with out any real effort -with a pair of compasses and a protractor. For me I have to draw everything several times over before I "check my maths" with a calculator... This enables me to see what the eventual item that I am drawing will; look like, and behave like -before I start construction.

The drawing above is for a device to "dampen" the "cold snatch" take up effect in one of my locos. Large motors require a warm up run and this device winds up via the springs and then once the loco is moving the springs unwind and the system returns to balance. I could have worked out the rotary torque required by mathematics -or simply do what I did treat it all as a straight line and do a simple Hookes law conversion. YES -the results will not be accurate for the spring ratings -but it can be done on a piece of paper and not require any deep maths to go wrong!

If the motor generates 20Nm then the 10:1 worm and spur steps this up to 200Nm I need a spring that goes flat in 0.01m thus I need a spring with a rating of 2Nm...

There are several very complex formulae for working out how long an arm is required to correctly position a Bissel Truck or Bissel Bogie this however is the one that I use:

The length of Arm is: (The total wheel base) Squared MINUS (The fixed wheel base) Squared DIVIDED BY (2 x the total wheel base)

In the case of my NYC "S" motor the numbers are: ( 9+5+5+5+9) sq MINUS (5+5+5) sq DIVIDED BY (( 9+5+5+5+9) x 2)

The answer is 9.98cm which comes as no surprise -as I had drawn it out at 10cm...

Another mathematical technique is "do not be afraid to fiddle with the figures to get nice numbers" (the string of "4"s in Bodes Law does that...) If your measurement calculations require two places of decimal then you are doing them wrong round up to integers and work from that. The pieces may be too big -but they can always be made smaller to fit -the reverse is not true!!!

The last piece is philosophy, if welding your chassis terrifies you -then don't design it to have to be done that way! Modern epoxies and even pop rivets work just as well and more importantly -you can change your mind during the process...

I would also advise you to question the validity of your critics. There are 3 main 4mm scales called OO EM and P4. Each uses the same 4mm to the foot scale but differing track gauge. OO is 16.5mm EM is 18mm and P4 is 18.85mm. I have to ask myself is this P4 really what I am looking for -modelling to an accuracy of 10 MICRONS??? I use the 10 foot rule for my models and yes I am short sighted!!! I think I fall into the artistic modeller camp rather than the prototypically correct engineering camp. I would far rather be happy with my slightly trapezoidal door than worry that the edges were not cut to 80 degrees 45 Seconds of Arc -as they were in the original...

So there you have it. A small missive on Technique-ology, the rest you can write for yourself!!!