Q&A

Question:

The person who took my phone order for a set of chisels mentioned something about "lapping the back." What's that all about?

Answer:

Lapping, the business of flattening and smoothing a tool surface, is a standard part of tuning and sharpening most new chisels and plane irons. Brand new tools (with rare exceptions) are NOT sharp, so right off the bat you know you'll need to polish the back of the tool as well as the bevel to produce a good sharp edge. As you begin polishing, you'll notice that 95% of new tools are not entirely flat, either. The back of a chisel acts like the sole of a plane, giving the tool a reference surface so it can make straight, predictable cuts. Good performance, then, requires that the back be both smooth and flat.

You can lap your chisels on sandpaper by hand on a machine surface, on diamond stones, or on ceramic stones. Perhaps the quickest and easiest way to flatten and polish the back of a chisel or plane iron is to use our Work Sharp 3000 machine's 6" diameter tempered glass wheel coated with adhesive backed sandpaper. The Work Sharp also works quite well maintaining and honing a tool's bevel at a repeatably precise angle, and uses an air-cooled heat sink that prevents burning and loss of temper without the need for messy lubricants.

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