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I'm hoping someone on here will know a good range of rockwell hardness numbers for H and I beam steel rods and the same for a decent forged steel crankshaft If I'm remembering correctly the first batch of Ohio Forged Steel Crankshaft CO. I bought where between 22 and 25C rockwell The crank grinders and machine shop I used at that time in SO CA thought that was to soft, I didn't have those reheat treated I have one of those cranks in my 505 C.I. bracket motor and found out recently there is a heat treating company near by, so I thought I would ask on here first and see about having that crankshaft reheat treated next winter, if it really needs it One other question, what do you guys pay for heat treating a B-RB forged steel stroker crank and for a set of 8 rods?



22-25 rockwell C is like butter....a file is 62 Rc
and I would think good quality steel is 45-50 Rc...
you dont want them too hard but no where near 25Rc
EDIT
Axles range from 57-59 Rc





Yeah and files snap like twigs when you put any kind of load on them as well, not exactly what u want for a crank. U can take 4140/4340 to the low mid 40's for RC with full heat treating but that's where u want it for making vice jaws, tooling (not cutting tools), and for something thay needs high wear resistance. The higher u go for RC, you lose toughness and maleability, which a crank needs. Go to most any machine shop and ask for a shaft/ bushing whatever to be made and it needs to put up with alot of abuse (loader bucket pins/bushings etc) and they go right to there rack of 4340 and use that in its non heat treated form, which is in the mid 20's for RC.
With all the torsional/longditudal forces on a crank I don't think u would want it very hard, although my experience is from the general maching end of it so I could be wrong