Pattern Router Bits
image by Photos by Gene Tencza
A pattern router bit is a straight cutting bit with a bearing or "pilot" on it. The bearing runs against a pattern or template, and the bit cuts your workpiece to the exact size and shape of the pattern. The pattern can be as small as a hinge mortise or as large as an entire table top. Whatever the pattern is, you will reproduce its shape on your stock.
Make a pattern that is the size and shape you want final piece to be. Be sure that all the edges are sanded smooth.
Place the pattern on the work and mark the work with a pencil.
Remove the pattern from the work.
Make a rough cut of the work, staying about 1/8" outside the pencil line. Use a band saw, saber saw, coping saw or whatever is appropriate.
Selectiing the router bit
Use a bit with the bearing on the end if you want the pattern to be beneath the work
Use a bit with the bearing on the shank if you want the pattern to be on top of the work.
Select your bit and mount it in the router.
Making the cut
Clamp the pattern to your work, carefully matching it up to the previously made pencil line.
Turn on the router, place it on top of this assembly, hold it firmly and carefully push it into the work until the bearing touches the pattern.
Proceed around your work only as fast as the router will cut without laboring.
Stop at a convenient spot (such as a corner) and move your clamps to an area that has already been cut, then proceed with the rest of the cut.