It machines really nice, just need sharp tooling and don't get it hot or rubbing

I used to have access to cyanide case hardening which was ideal for such an application ,leaving a clean finish although I don't know if you can still get this done. I don't think tempering is needed or desirable for high speeds. a 10 thou. case would be OK. Colin

Edited By colin hawes on 28/01/2013 15:28:42

I agree with Colin, cyanide harening or what is now used instead of cyanide commercially will work fine.

There is no need to temper EN36 as it's not a thru hardening steel, the core stays tough as opposed to soft.

EN 32,33 and 34 are thru hardening steels which need to be tempered or they can become too brittle.

The untimate without resorting to specials is EN39B which is like EN36 on steroids, just stronger and again not thru hardening.

We make crankpins for racing engines out of this if they are one piece as it combines hardness with toughness.