A while ago a few of the builders on a private messaging group (I run for youngsters), had a discussion on how to measure oneself as a model engineering builder. We came up with 5 (arbitrary)’ levels’; each one unique in complexity and requiring a different set of applied knowledge. Simply put they were as follows:

1.       Model engineering basics(basic fitting and turning, limits and fits)

a.       Successfully quartering a set of wheels with no rattle fits on the bearings and connecting rods and of course no binding.

b.      For the traction guys, it was a set of gears that mesh uniformly with a plastic shopping bag that is not loose at any point, or crushed.

c.       Another one was a steam tight but mechanically free piston fit.

2.       Successfully making and testing a boiler. (soldering, fabrication)

3.       Casting your own components. (metallurgy)

4.       Making a live steam injector suitable for your build. The smaller; the greater the skill set. (precision turning and taper turning)

a.       Another one was a leak free clack without smashing the ball onto the seat to get it to seal. (Machining a hole ‘rounder ‘than  a commercial reamer)

5.       Successfully making a pressure gauge. (instrumentation calibration)

Most of the builders here scored an easy 2, very few scored 3 or higher and those that did typically had a number of builds under their belt. Of course the elder low scorers argued the existential nature of model engineering; that it’s only for fun, this is an arbitrary list, these are impossible, I don’t build like that etc. etc. (at which point I had to smile).

This was just for fun to give the youngsters something to aim for (goal driven accomplishment). I did wonder how well the members here would do? BTW this was for live steam (most of the guys either do loco’s or traction engines), but I’m sure similar lists can be made for IC engines etc.