The last material would be1144 stressproof steel. I was put onto this material many years ago by a good friend and fellow modeler and have never use anything else. It machines very nicely and distortion is minimal. gbritnell
I read your prior similar comments about this material a few years back & followed your advice. I'm only making a comparatively simple crank for a radial, but you are right, very nice stuff. Not easy or particularly cheap to get into Canada (USA suppliers) but fortunately not that many components to make. I believe you also used them for cylinder liners on one of you engines? I made a few testers for my radial including 12L14 & cast iron but think 1144SP will be the way I go for those too.