Cryo dont sound cheap, might be able to buy 5 new bits for the cost of re-tempering one.
As far as re-tempering during the weld - once the new metal is on, I can temper that new metal by a few quick dunks in the sink and be harder than the original metal. Twisting - good point, but doubt I'll notice it. I'm gonna give a few a shot this week end - I'll let you know......
