Old Files

[wolfy9005]

Just a quick question, but how would you go about turning an old file(say a bastard file ~6mm thick and 350-400mm long) into a decent, sharp knife? Would i have to soften(forgot the term....it's late, gimme a break) it then re harden it or just grind it sharp with an angle grinder? Im thinking it would have to be kept cool to stop it heating upand ruining its desirable features(strong, keeps it's edge) but it isnt very flexible.

Any advice will be appreciated.

[ThomasPowers]

You can grind a file into a knife without having to reharden. First thing you will need to draw temper on it so it's not so brittle. This can be done in a regular home oven at (depending on alloy, type of balde, personal preference, etc) around 375-475 degF with the higher temp making for a tougher blade.

Then you will need to keep it cool while grinding to shape---use sharp abrasives, don't push too hard on it and keep dunking it in water!

[JAFO]

How long do you leave the file in the oven?

[steve sells]

2 hours will be good.