Office of Steam Forum for Model & Toy Steam Gas & Hot Air Engines

Well, I just got done milling the steam chest out, and I must say I'm happy with how this has gone. I had to put together a coordinate diagram for it, and then carefully keep track of my handwheel positions, because I don't have DRO's (not likely to add these in the foreseeable future), and also made sure to write down diagrams to remind me which way to turn the handles (sounds obvious but I've fallen foul of that before).

Anyway, I'm 2 thou over on the depth of the chest, which is within my general tolerance goal of ±0.005 so I'm pleased. Looks decent too, in my opinion.

Now I'm trying to decide how to center the slots in the bottom of the chest. I can easily do that from the sides of the steam chest, but then how to center the bore in relation to that? Need to give that some thought. I have a feeling that if I center the slots in relation to the casting OD, that everything will line up well enough. Have to double check dimensions on the valve etc, make sure everything will work if I do that. Also need to get some small milling cutters, so this is it for now. Got to go and do some  chores. Leaving the cylinder where it is for now, because I want to mill the slots, and also drill the holes for the cover before moving it.