Wednesday, May 13, 2009

Learning to Sharpen Chisels

Let's face it, I never started out to be a hand tool guy. There is something about power tools that just draws me to them. Among other things, they have (for me, at least) a mystique about being precise in application. Though I'm finding out they are only as precise as their user, still, the whole idea of hand tools leaves me with the impression of their being susceptible to misuse by my unpracticed hands.

Be that as it may, I have already found chisels handy enough (OK, essential) that I broke down and bought a set. I didn't pop for an expensive set but instead caught Woodcraft's Wood River brand when it was on sale. What I didn't count on was the fact that while they are not exactly dull when they arrive, they do need a basic sharpening to make them really useful.

The first thing I did was purchase a basic grinder, which is needed to shape the front of the blade. But after asking my friend Jeff Fleisher how to sharpen them properly, he put me on to an article about David Charlesworth's method. Finally, today I drove out to his shop in New Market, Virginia, and he helped me sharpen the first chisel so I could see and experience the process for myself.

The process is fairly straightforward, if a little tedious when doing it for the first time. Charlesworth's method calls for a series of Japanese waterstones. You first flatten the back (flat) side of the chisel to remove all the tooling marks as it comes from the factory. This involves working the back of the chisel up and down and then back and forth on either a 200 grit stone or wet or dry sandpaper laid wet on a sheet of glass. When the factory marks have been removed, only slight scratches from the stone or sandpaper should remain. You then move to a 1200 grit stone that has been wetted and repeat the procedure, working from there to a 4000 grit stone and finally an 8000 grit stone on which a slurry has been made with a nagura stone. By the time this has been done, few if any scratches should remain and the back of the chisel should be both flat and scratch free.

The next step is to work on the beveled side of the chisel blade. Here you turn to the fine wheel on a slow grinder. You mark the beveled edge with a Sharpie, then grind away the marked metal, holding the chisel at precisely 90 degrees to the wheel. When all the marking has been ground away, you should have a slightly concave surface on the bevel.

The final stage is to put a fine edge on the chisel. This is done on the 8000 grit stone using a device that holds the chisel blade at 30 degrees to the stone. Five or six pulls is all that is needed. Then you increase the angle slightly and repeat the process, again five or six times. All that's left now is to check and see if there's a burr on the flat side of the chisel and, if so, remove it by pulling the blade across the stone a few times.

The finished blade should be able to cut the top of your fingernail when gently pushed against it or should be able to shave a piece of soft wood like pine smoothly and cleanly.

So, I now have one sharp chisel. And a lot of work to do to get the rest of them ready for real use. The good news is, once the backs are flattened (the slow part of the process), I should not need to do more than touch up the bevels for a long time to come!


Thursday, May 7, 2009

Preparing to Make Boxes

Today I jointed a sycamore board that I plan to use to make tissue box covers. Because it was 8 1/2 inches wide, I had to take the safety guard off my 6 inch jointer and run it through one end after the other so both sides would be smoothed. Planing it was no problem; my 12 inch planer did a good and quick job on it. When I finished the rough side, I ran the jointed side through one time to remove the groove left by the edge of the blade from the final pass on the jointer.

It was then that I turned my attention to my band saw and discovered that although I need 7 inch stock to resaw for the boxes, my saw will only accommodate 6 inches. So I got on line with Grizzly, the maker of my band saw, and ordered a riser kit for my saw. That will give me 12 inches of resaw capability. Now I'll have to get a new 105 inch saw blade to replace the Wood Slicer resaw blade I've never even used. I hope Highland Woodworking will take an exchange on it.


Wednesday, May 6, 2009

A Bad Day in the Shop

Woodworking is fun and most days spent in the shop are rewarding and, usually, successful. This wasn't one of them. It began when I set about removing the dado set from my table saw. After neatly packing it away in its case, I got down several saw blades from their peg on the wall to select the one I wanted to install next. As I moved around the table saw, my loose shirt tail caught the teeth of one of the saw blades and dragged it off onto the floor with a resounding clang. Upon inspection, I saw that one of the teeth had been damaged and there was nothing to do but consign it to the waste can. It was a Forrest Woodworker II blade, my best and most expensive one.

I chalked that one up to experience. Then I moved on to cutting the fences for a miter jig I'm building. The next step called for cutting through the aluminum T-track I'd installed in the maple fences. My table saw, a SawStop, is equipped with a safety system designed to stop the blade if it touches anything conductive, like a finger--its intended purpose--or soft metal, like aluminum. There's a bypass procedure, however, that allows the saw to cut aluminum without triggering the safety system. So, armed with what I thought was the correct information about using the bypass system, I proceeded to cut through the first piece of fence. No sooner than it had touched the first bit of aluminum than I heard a pop and the blade disappeared below the tabletop. After opening the table, I saw the results of my misguided handiwork--the safety device was firmly attached to the now-ruined saw blade. Scratch another blade and chalk it up to . . . experience. The good news is, the safety system works.
Now wiser about the bypass procedure, I installed my remaining saw blade and a replacement safety cartridge I'd had the foresight to purchase. Then I cut the aluminum-studded fences with no trouble. I learned a lot today. But it was a costly set of lessons.