Thread: Heat treating mucked up ?

Sounds like you'll be able to salvage it if you continue to grind without anymore over heating.

What I do is keep a bucket of cold water next to the grinder and dip the blade in the water after every pass. It's probably overkill but decidedly better than the alternative.

You could also use one hand to hold the tang and the other to support the opposite side of the blade with your fingers (or thumb) touching the steel where it is being abraded on the other side. If your fingers start to burn, take the blade away from the grinder. You'll never overheat the blade this way because your hand will burn at 200 degrees lower than it takes to harm the steel.

Originally Posted by Russel Baldridge

Sounds like you'll be able to salvage it if you continue to grind without anymore over heating.

What I do is keep a bucket of cold water next to the grinder and dip the blade in the water after every pass. It's probably overkill but decidedly better than the alternative.

Exactly what I was doing ... even had ice in the water.

You could also use one hand to hold the tang and the other to support the opposite side of the blade with your fingers (or thumb) touching the steel where it is being abraded on the other side. If your fingers start to burn, take the blade away from the grinder. You'll never overheat the blade this way because your hand will burn at 200 degrees lower than it takes to harm the steel.

Again exactly what I was doing - fingers didn't burn but the metal still turned black... this is what surprised me. I did everything I could to prevent overheating and I though I was doing an alright job but a couple of spots just appeared to spontaneously flare and go black without feeling excessively hot to the touch.

Still you live and learn. I should get some time to continue my experiments next week.

Thanks for everyones input.

Barney

The fact that your fingers didn't burn might be caused by the fact that you were holding the spine / tang and not touching the blade enar the edge.

When I grind away pitting on my low speed home made sanding wheel, I keep my fingers of one hand near the edge, with my thumb on the spine.
My other hand holds the tang.

That way I can feel the edge heat up. When it gets to the point of being uncomfortable, I simply take it away for a couple of secs. it'll cool soon enough.
The blade near the edge is very thin, so it will heat up to damaging temperatures a lot quicker than the spin, which has a lot more mass to it.