I’d been thinking about how to cut the slots in my box lid for the miter keys. The narrowest blade I have is my 1/4” chisel. Actually, I think my mini router plane blade is a touch smaller than that, but would still have cut far too wide of a slot. So here’s what I came up with: the allen chisel. My idea was to simply (simply, ha!) grind a bevel on an allen (or hex) wrench and then hone it up on my stones. I don’t have a grinder, so I had to do all my grinding with a file.
Well, it wasn’t actually quite that easy. First, I realized that when you grind the bevel on a hexagonal wrench, the “meat” of the bevel is wider than the cutting edge. This would make for a pretty sloppy groove. So what I had to do first was to grind the sides of the wrench to square the edges, essentially making it rectangular at the front. Then I could grind the bevel. I tried to estimate a 25-30 degree angle, and when I measured it with my Starrett protractor, I was pretty close. I just needed to touch it up a bit and I was in business. Take a look:
Honing the allen chisel was a bit unnerving. My stones cost a lot of money, and I didn’t particularly like dragging a little tiny blade across it, making little tiny grooves. Also, on two occasions I raised the “handle” just a tad too far and made a couple mini divets in the surface. Great. Needless to say, I didn’t put a microbevel on this sucker. Here’s another pic:
Someone told me that an allen wrench isn’t tempered or hardened or whatever, and that as a result, it wouldn’t hold an edge. I figured no problem, I’m only using it for a few inches of grooves; it should stay sharp enough for long enough.
Stay tuned for the next post to see the allen chisel in action!
-- Eric at http://adventuresinwoodworking.com