I have a production project in the plans which will require mortising and bent lamination, so I took the time to build a mortising jig and a beam compass. I will be test driving them after the project design is approved on Labor Day weekend.
Mortising jig
The mortising jig design is original, but has features borrowed from Jeff Miller and Philip Morley. It is approx. 16”x 30” x 5” with a ¾” x 5” x 36” base boards. The primary materials used are 4/4 maple lumber, ½” Baltic birch ply, and ¾” Prowood birch U-V ply. The red stops are made from scrap cherry painted. The jig can be easily clamped to a work bench and all of the accessories can be stored in the back of the jig.
The work piece is referenced on primary, secondary, and ternary surfaces. The primary surface is made from two pieces of birch ply glued together. Clamping takes advantage of the Microjig dovetail clamp riding in a 14 deg. dovetail track groove. If your work piece is difficult to load and reference when the jig is up-right position, the jig can be positioned horizontally, so that it takes advantage of gravity loading. The clamps have a limitation of a 4” opening with 595 lbs. clamping pressure each. The router edge guide maple runner was machined at the same time the guide groove spacer. During assemble a paper shim (~0.004”) was added to allow the guide to run parallel to the work piece. All surfaces received a light coat of Johnson paste wax.
Beam compass
The compass was built from scrap ¼” x ¾” x as needed cherry material. It can make an approx. 14” radius. The design is not original.
Danl