I am making a woodcarving knife. I started with an old file. Files are made from very hard steel — They are intended to work softer steels. So the first step is to soften it up. This was easy: Last summer when we were grilling something I put the file deep in the charcoal, and let it stay there through the grilling and while the charcoal cooled afterwards. This is called annealing. It softens the steel so it is easier to work. I cut most of the edge with a bench grinder, then cleaned it up by clamping the blade to my workbench and using a sanding attachment on an electric drill:
It is beveled on just one side, like most woodworking tools. The bevel angle is about 30o, which is a standard angle for woodworking tools. I need to complete the final shaping of the blade, then heat-treat it so it can hold an edge. After that I will add a handle and hone the edge.
If this works I may try it again on a considerably larger file blade that I am not using, It would be cool to have my own homemade Scottish dirk for colgaffneyis.