Assembly Check No 1
At this point in construction I assembled to parts machined so far, to see how well things fitted together. If you have made the parts in the same order as me then you will have machined all the major castings with the exception of the flywheel. There is more drilling and tapping to be done once mating parts are completed but all the major machining is done.
The engine so far, standing on the assembly bench
I found very few problems at this stage the piston was a slightly scratchy fit in the bore but this would bed in with time. However, I had to open out all the cylinder cover holes by 0.1mm to provide an easier fit. I also had to enlarge the holes in the bottom of the standard by 0.2mm to give enough movement to square things up. The holes in the steam chest had to be opened by an amazing 0.5mm to get a nice fit. I put this last problem down to the fact it was very difficult to drill and tap the studs for the steam chest exactly square and because they were over an inch long any slight error was magnified. Anyway the end result was still acceptable.
My only real concern was that the piston rod was not parallel with the front of the standard. I suspected this was due to my method of machining the top face of the standard using the side of the milling cutter which may have deflected. This would need to be corrected later either by
re-machining or by careful filing.As well as checking for fits, seeing the engine start to take shape was an encouraging site, helping provide momentum for further work. This was important with someone like me who gets distracted easily.