I like to reinforce the miter joints in my picture frames by adding a contrasting key after the glue in the joint has set. The usual method of cutting the key slot is with a tablesaw and a vertical 45¡ jig riding on the fence, but I find it easier and safer to make the cut on the router table with a slot-cutting bit. The jig, shown in the sketch above, can be made in just a few minutes and has the advantage of enclosing the spinning bit throughout the operation. The resulting slot has a flat bottom and is uniform in width. Inexpensive bits are available to cut slots as narrow as 1/16 in., which looks better on a small frame than the 1/8-in. slot produced by a tablesaw’s blade. On larger frames, I cut two slots by setting the bit a little below the centerline, cutting the first slot and then flipping the frame over for a second pass.

Paul Davis, Lake Stevens, Wash.

Fine Woodworking Magazine, August 1992 No. 95

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