Tool Sharpening Made Simple

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Photo courtesy STEVE MAXWELL
While sharpening stones can work well, buffing wheels offer a quick and effective alternative method for tool sharpening.

The best way to sharpen tools, such as wood chisels, plane irons and knives, doesn’t necessarily involve sharpening stones. Even though I own a dozen fancy stones, I don’t use them anymore. Instead, I turn to my shop-built buffing wheel, because it works so quickly and so well. It’s also very simple.

Picture a hard felt disk about 8 inches in diameter and 1 inch wide, its edge saturated with a fine, waxy abrasive compound, mounted on a spindle spun by a motor. That’s all there is to a buffing wheel. You press the edge of a dull tool against the edge of the spinning wheel, and in a minute or so it’s sharp enough to shave hair cleanly.

You’ll need to address a couple of preliminary details to assure consistent success. Before using the buffing wheel, grind the tool edge to the proper angle. For conventional woodworking chisels and plane irons, this means a tip angle of 25 to 30 degrees. Most new tools come ground to an acceptable angle, though eventually you will have to re-establish this angle. Tool angles get blunt after repeated use and honing. And don’t procrastinate; once you get past a bevel angle of about 40 degrees, you won’t be able to hone a sharp edge, regardless of the sharpening system you use.

A bench grinder with a cool-running abrasive wheel is a good choice for correctly shaping woodworking tools before final honing. Cool-running wheels are made of aluminum oxide with a relatively soft bond and cause much less heat buildup on the tool than regular grinding wheels. This is significant — if a chisel or plane iron gets too hot to touch, the properties of the steel will change so that it can’t hold an edge for very long. Even with a cool-running wheel, dip the tool tip in water after every three or four seconds of grinding time, just to be safe.

For successful grinding, mark a 30-degree angle on a piece of paper, or use an unworn tool as a visual reference. Hold the edge of the dull tool steady at a 30-degree angle to the edge of the spinning grinding wheel, with the edge pointing in the opposite direction as the rotation of the wheel. Always use a rest to support a tool while grinding. Besides being necessary for accuracy, it’s crucial for safety — it will prevent the tool from being caught and hurled dangerously.

  • Published on Feb 1, 2007
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