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jylong_away
11-28-2010, 06:04 PM
Sorry in advance if this is in the wrong forum - please feel free mods, to relocate!

I've made some rings from Chad Nichols' Cheetah damascus, and they're currently at the local HTer being hardened.

In the meantime, I've stumbled on a design modification which I'd like to implement on one of those rings. It involves only grinding down of parts of the ring.

With regards to belt grinding hardened steel, I've heard things about overheating and losing temper, etc. Some have said to water quench it every 2-3 secs on the grinder, and others have said to just not let it get too hot that you can't physically hold it with fingers.

Can anyone share some tips about their recommendations for grinding hardened steel, without messing up the HT? Thanks!

David

BossDog
11-28-2010, 06:52 PM
Keep the temp below 350F and you will be fine. Grind a little and dunk.

Doug Lester
11-28-2010, 10:17 PM
Do your grinding with bare hands and you won't be able to hold it long before it ruins the temper, with some exceptions. If you are grinding really thin parts, like the edge of a blade, it can still overtemper even though the thicker part hasn't gotten too hot to handle. If you're not holding close to the area being ground, by the time you feel the heat in your fingers the work area may have overheated. If in doubt, make a pass or two then stick it in a bucket of water.

Doug Lester

Mike Turner
11-28-2010, 11:11 PM
And use new belts they cut better and cooler than worn belts

jylong_away
11-29-2010, 04:28 AM
Thanks for the info everyone! Rings should be back wednesday, so will have a go at it then. Good thing I stocked up on new belts yesterday! Just finished a Ti version of this 'new' ring design this evening..really excited!

Les George
11-29-2010, 09:37 AM
rule #1 grinding heat treated steel, if you think you can get by with just one more pass before you cool it off, you are wrong. ;)

jylong_away
11-29-2010, 03:21 PM
Thanks Les - I needed a few rules of thumbs such as that! :) Guess I'm gonna be taking it *really* slow for this one. Good thing I managed to get it really finished before sending for HT!