The concept is simple, but this jig is indispensable for routing dadoes in carcase sides, especially when several dadoes are to be made in one board. Once the jig is clamped together you can slide it quickly into position for the next cut.

Make up two L-shaped pieces with 4-in. wide plywood strips. Cut the shorter pieces of the L 16 in. to 18 in. long (router base plus 8 in.) and the longer pieces 20 in. to 30 in. long (widest carcase plus 8 in.). Face-glue and screw the pieces together, taking care to maintain a 90¡ angle.

To use, place one L on the front edge of the board to be routed and one on the back edge so that the two L’s form a woven rectangle as shown. Adjust both directions to give a slip fit against the router base and against the sides of the board. Then clamp at the intersections of the two L’s. Pencil in an index mark on both sides of the jig to simplify lining up for a cut. Clamp the jig to the board before routing the dado.

Roger Deatherage, Houston, Tex.

Fine Woodworking Magazine, August 1979 No. 17

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