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the rounding on that side of the edge also is removed and the red ink is all gone. You can polish through as many finer papers as you need to achieve the desired result.

For a knife edge the process is similar. Only here, use a medium-grit paper on a block or dowel to

remove the line of polish that reveals a rounded edge. Now, work in the same way through the finer grits.

Routine honing brings back a sharp edge for a while. However, repeated honings will eventually remove enough metal from the cutting edge that you begin

to change the blade's angle. The angle can increase to a point where it no longer cuts well. If the blade is mounted in a tool such as a plane, it can even lose the clearance behind the cutting edge that's required for the tool to take a shaving. In most sharpening methods, this requires going to

the grinding wheel. With sandpaper sharpening, you return to the #80 grit and reestablish the original angle through the aggressive abrasion of a coarse paper. Now, hone the newly shaped edge with finer papers. PW

Next issue: Dunbar on setting up handplanes.

SHARPENING PHILOSOPHY:

DON'T Go CRAZY; USE YOUR JUDGMENT

Here are some general thoughts and advice on sharpening, as well as answers to some frequently asked questions. Every shop should have a dedicated sharpening system. You should work with sharp tools. It is easier and safer. You are less likely to stop and hone a tool that is beginning to skate if you have to dig out your sharpening equipment and set it up.

Sandpaper sharpening is a complete system. I not only maintain all my personal tools with it, we maintain the many score of tools we provide for our students' use. Fred Chellis, who teaches with me, runs a sideline sharpening service, and uses the sandpaper system. When sharpening as many tools as we do, one wants a system that is fast. However, there is no reason why the method cannot be blended with other equipment you may already own or prefer. For example, Fred likes diamond hones and uses those instead of wet-and-dry paper applied to a wood block.

How flat is flat? I receive e-mails and read comments from people who are unsatisfied with a lapping plate because when tested with a dial indicator or other precision equipment it was out of flat by some otherwise imperceptible amount. Don't go crazy here. Over the years obsessive-compulsive authors and letter-to-the-editor critics have convinced too many of us that we cannot work wood unless we are accurate to three decimal places. Remember, when lapping we are sharpening woodworking tools - not making equipment for NASA's Mars Rover.

How sharp is sharp? The answer to a lot of woodworker questions is, "It depends." In this case, it really does. Not all tools have to be equally sharp. A tool one woodworker relies on for finish work, such as a plane, another may use for rough stock removal. Generally speaking, chisel-edge tools will need to be sharper than knife-edge tools. The former are more commonly used for finish work, while the

The sharpening system outlined here works for the wide variety of edge tools for woodworking, including the small selection shown here that I maintain for my chairmaking classes.

latter are for shaping and heavy stock removal. I only take my drawknife up to #330 grit, but my best Bedrock 404 smooth plane is honed to a bright mirror polish on #1,500-grit wet-and-dry paper.

What angle should I use for my cutting edges and how accurate do I have to be? This answer combines the last two. It depends, and don't get crazy. The more acute the angle, the more easily it will cut. However, the more acute the angle, the more fragile the edge. So, the heavier the work you do, the less acute (or more robust) the edge. For example a jack plane blade's edge will have less angle than a smooth plane. Mortise and firmer chisels have more robust edges than paring chisels. Don't get wrapped up in how accurate your angles are relative to what you read or hear. If some

one writes the proper angle for a tool should be 35°, do you think it will matter if you really get 37°? No. In other words, use your judgment.

I think (insert any system here) results in a sharper edge. Assume there is a sharpening scale of 1 to 100. If your tools were only at 50 on this scale, would you complain if a system resulted in 93, as opposed to another that created 95? I once visited a shop run by a real sharpening fanatic. He was so proud of his edge that he gave me jeweler's loupe to watch the action as he shaved hair. It was not like shaving your beard, he shaved along the follicle like you would whittle a stick. I asked how long such a sharp edge would last in a plane. He replied: "About a half dozen strokes. Then the super edge wears to merely sharp."

How often do you sharpen? Sharpening is a function of use, not time. Simply put, sharpen when you need to. A dull tool requires more force and does not create a cleanly cut surface. You can also see the rounded edge under good light.

What about micro bezels? I don't use them and my tools cut fine. Sandpaper sharpening is real easy, and I don't like to complicate what can be done easily. — MD

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Popular Woodworking April 2007