Q. I recently blued the edge of a chisel, mainly because I was in a hurry when trying to grind past a small chip. How bad is the damage shown in the photo? What are my options for getting the chisel back in top condition?
—Roger Angelof, via email
A. Senior editor Tim Snyder replies:
It’s a good bet that most woodworkers learn the hard way that grinding can easily damage tool steel if you’re not careful. This is especially true when you’re grinding close to the tip of the chisel, where thin steel can overheat quickly.
To repair your chisel, you’ll first have to grind past the discoloration. Push the chisel’s tip straight into the wheel, creating a flat surface that resembles the tip of a screwdriver. Make sure this new surface is square with the chisel’s sides. Then get to work on reshaping the bevel, taking care to cool the tip in a bowl of water when you feel the steel get warm. Aim to create a hollow grind as shown in the drawing. This approach leaves room for a narrow (1/16" or less) microbevel, which won’t take long to hone.
Pay attention to how your new edge holds its sharpness. If it dulls easily, this means that the damaged steel extends beyond the discoloration. You guessed it: more grinding.