I put this together based on a picture of a compound jig that is used on a wide-belt sander. I should have taken more pictures as I went along, but you'll get the idea from the finished product.
The radius at the nut is 16", and 20" at the saddle end. After doing a full scale drawing, the axis shaft was 100deg. I laid out the shaft locations for the outside box and for the FB carriage, and drilled over sized holes to accommodate the 1" dowel shaft.
I cut four plywood pieces at 100deg to trap the dowel at the inside of the carriage, and outside of the box, and made some UHMW washers to keep everything snug.
The router carriage is made from 1 1/2" aluminum angle and 12mm pre-finished ply, and sits on height adjusters. This allows adjustment to be made
to get an even thickness on the edges of the FB. On the test FB shown, thickness at the nut is .20", at the soundhole .21", and .17" along the edges.
Alex
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