Use a belt sander...

[russianpolander]

Just purchased a belt sander(Sears 2''x42") and have a few newbie questions.

1) If I use a belt sander to sharpen a knife will I have to temper or HT again?

2) lets say I want to change some edges to convex, do I use the platen or remove it and use the slack portion?

3) I also have a grinder that has variable speed, can I use it to sharpen if I go slow?

4) how hot is too hot? Meaning how hot can you get a finished blade before you mess up the temper?

Any input is welcome, thanks in advance.

SEMPER FI TIL I DIE

 

[Justin King]

1-not if you do it right
2-you can convex either way, the slack belt does a little bit of the work for you
3-low speed works better than high speed to keep heat to a minimum while sharpening
4 there is not way to really register the point where the very thin cutting edge gets too hot, it depends on the steel type, original tempering temperature, etc, and to complicate matters even more, the steel at this very thin edge can over-heat and cool back down in seconds, making it hard to know if you have allowed it to get too hot.
I sharpen on the grinder with a sharp 120 grit belt using very light pressure and quick passes. I only do this to establish the edge, then go to diamond hones to refine it.