you gotta admire a guy thet makes his own foam patterns for his own castings for his own design and then machines them and assembels them into a working thing of beauty.
My ownly other question is what is your anticipated operating pressure and then what does the engine wiegh?
I'm still in the design stages of a 3cyl engine with a relitivly small bore and stroke that runs on 1000psi steam. The plan being to reduce the size and wieght of the engine and steam consumption by running at the higher psi.
I get no help from the guys in the steam clubs I belong to on this because they are all fire tube/traction engine and locomotive types and get scared when I start talking about high pressure water tube boilers and the like.