ive got a question about a Forge Craft Hi Carbon chef's knife. the edge is rounded and the tip of the blade has a nasty nik in it that cant be simply removed, too large. ive been thinking about making it into something else and considering that i dont have a forge built yet i was thinking maybe a seax or a stileto. i would like to know if taking this to a grinding wheel or an angle grinder would damage the temper or not. ive never worked with this high carbon of steel so any adice or comments would be greatly appreciated. thanks.

Yes grinding on it will to ruin the temp it has now. as the metel heats up from grinding or cutting the temper will be lost at the point you grind on it. This will be evident as you see the colors change while grinding on it. However with a forge, oxy/ace torch, or even just a BBQ grill, you can restore the hardness to the steel and then retemper. I say experiment with it. read all you can before starting and then what's the worst that can happen, you learn what not to do next time.

I would suggest reading all you can find about the colors involved with tempering, learn what the color progression is, and use it to retemper after you get done reworking your blade.

And as always...post plent of pictures including a before and after pic.

tim

You can "cold grind it" with care. Run the blade across the grinder, then dip it in cold water, repeat. As an unskilled blademaker you are very much less likely to mess up the blade doing it this way than to do a re-heat treat on it! (You can also use an angle grinder to "lop" excess off *but* you must do it far enough from the "wanted" area that you can then cold grind off any heat affected zone.)

you make a good point.

one thing about chef's knives is the edge is very thin and the cross section is a triangle so there isn't a lot of mass to keep it from chipping or cracking. the geometry is great for a knife to chop wegetables or meat bus could be a bit frail for a working knife. it would make a great skinner or boning knife. also factory knives are tempered the same throughout, so the spine is usually as hard as the edge. and i would suggest using an angle grinder to finish and the grinding wheel to get rid of steel. ive reground a few knives and after breaking the first i started drawing a bronze to blue color only on the spine, not to the edge, and this makes them a bit tougher rather than brittle. only used carbon steel knives because i dont know how to treat stainless. like Mr. Powers said, dont let it get too hot when grinding. also if it gets too hot to hold its too hot.should be able to make a servicable knife from it
that was a bit longer than i intended but if it helps it doesnt matter

good luck

Ed Steinkirchner

Many makers grind thin stock knives after heat treating as long as it is not heated hotter than you can hold or 400 degrees it will be fine. Take your time and cool it often in water i cool after each pass on the grinder.

Bob

The basic idea is that you can take a heat treated blade right up to the original tempering temperature with no issues; bladesmiths often temper a blade 3 times to get *better* results---get beyond that and you are messing up the blade.

that helps lots guys, thanks, ill definitly have to try that cooling in between idea, sounds like it should do the trick. ill post the before pic later, though i wont be able to start for a few days, have to move someone into their new place, thanks again.