Thread: Will grinding tho round-point off ruin temper?

The point behind doing this barehanded is that you want to feel the temperature change so you don't overshoot the tempering temperature.

Grind a bit, dip it, grind some more, repeat. Take your time, the grinder will remove the metal eventually. Go too fast and if you see color change in the steel it's already too late. Go slow.

If it's too hot to handle, it's probably getting too hot for safety, but 100 degrees is pretty much nothing (is that Celsius or Fahrenheit?) to a piece of steel. As others have advised you, keep a large glass of water on hand and dip it every pass on the grinder; make the passes fairly short. Zip it across in one directin, dip it and repeat in the other direction (or run it the same direction each time; I doubt it makes much of a difference) Good luck on your grinding.

I completely agree with what Mike just said. Lots of guys have tried it successfully with a dremel. It isn't too hard. Also, I've heard it said that the temper starts to change at around 300 degrees. But I've only heard that, not studied it myself.

I've done it with a dremel successfully, and that was on hollow grounds.
It is actually really simple. You just clamp the blade in a vise and work it with a dremel.

Use high speed (less time for heat to spread)
Use fresh drums (remove metal faster -> less time to build up heat)
Don't linger in 1 spot (do not heat 1 single place, but spread the heat around)
Do not hold it to the metal continuously (give it some time to air cool between grinding strokes)

It is really very easy. It looks scary, but there is nothing to it.

A tempering oven will begin to produce a yellowish-bronzish blush at about 350 degrees Fahrenheit. Colors are subjective but that's pretty close. 350 is way too hot to hang onto bare fingered.

Bruno's idea of using the vise as a heat sink is a useful addition to this discussion. Extra mass will allow for more heat absorption. If you're quick you'll have a little more time to get the job done before you overcome the ability of the blade or heat sink to dissipate heat.

Then, there's this stuff: http://www.toolfetch.com/Brand/Heat_...bles/HF-12.htm

It's a paste that works as a barrier to heat transmission. It works too.