Cryo HT Duration

[WMW]

I'm new to knife making though an avid reader of your forum archive. I tried my first attempt at LN2 on ATS34 with a before temper of 400 for 2 hours, followed by 2 hours of LN2, followed by 2 hours of temper at 650. I ended up with a 63-64 RW. Any suggestion to get it down to ~60-61 (like two hrs at 950)? Second question, how long should you soak a blade in LN2? Lastly, does the type of metal make a difference in the LN2 soak duration? Thanks.

 

[rlinger]

Ten or twelve hours. Ten should be fine.

I thinkst your getting erronious hardness readings, on the way high side.

RL

 

[WMW]

Thanks Rlinger. I kind of suspected that. I'll try a couple more experiments and get a second hardness check. Appreciate the advice on duration.

Herb