Here is a close look at the dull chisel, just about to undergo the first stage of the tune-up. If you can keep things cool, they won’t be there. You can also see the chips in the flutes of the bit. The chips rubbing against each other can get hot enough to burn, and once that happens, the smoke and resins in the wood start to get sticky. There’s is a lot of friction between the chips and the metal as they work their way up the flutes of the auger bit.

If you look at the pile of chips, you can see that they are fairly large, and some of them are scorched. It wasn’t completely trashed, but the end was discolored, and the grinding marks from the factory were still visible on the outer faces. I found it in the cabinet in the base of our old mortiser, and don’t know what brand it is, or how old it is. Here is a procedure that will take less than 15 minutes and will give you cleaner, cooler cuts. Sharp is good, but with tooling used in a machine such as a mortiser, you hit a point where your efforts meet with diminishing returns. Before using a router bit, I dress the edge with a diamond file, and I usually touch up the chisel before machine cutting mortises. I’ve always been geeky about sharpening things, not in the sense of polishing chisel backs to #32,000 grit, but having a good edge before going to work.

Tuning up a bandsaw tockler