Further adventures grinding
Jeremy Osner
>More grinding tonight. The victims were: a cheapo 1/2" HD chisel made of soft steel, which I had damaged by using to pry something; and a 1/8" mortise chisel, which I bought at a flea market last year despite the huge chip in its blade, figuring I would repair it once I learned how to grind. (I think it is made of cast steel though I am not sure.)
Both ground much faster than the hard steel chisel I did last night. I was trying to avoid a hollow grind in both cases; the HD chisel because the blade is so soft, the mortise chisel because it is a mortise chisel. For the HD chisel, I just ground the chip out and then ground a large secondary bevel and then sharpened it on the oilstone; this took about 3 minutes. The main thing I had to pay attention to was keeping the bevel square to the side of the blade.
For the mortise chisel, I did as follows: first I ground the chip away. Then I adjusted my tool rest so it met the wheel at pretty close to the angle of the existing bevel, which was 35 degrees. I started grinding the bevel, quenching frequently, and when it started getting close to the back of the chisel, I lifted the chisel handle slightly, so the front and back of the bevel were ground at different angles to the wheel. Then I flattened the bevel out on the india stone, and honed it on the oilstone. It came out pretty well!