From: "MICHAEL DUDDY"
M. Duddy's universal building jig
Date: Thu, 21 Dec 2006 08:28:46 -0500
The material used in the jig is 1"x1"x1/16" aluminum square tube( very ridged and no twist).
The ends are 1 1/2" angle bolted in two places on the ends as you can see in the pictures. I checked the ends with levels and the jig is dead straight.
The angle pieces with the screws in them are 3/4"x 1/16" x 6" long. You mount your frames to these with a square on the centerline of your frame inline with the center of the attachment piece.
Next you use a square to square these on the jig rails, and line up with the string. Now you are rite on brother.:) The dimensions of this jig are ; 60" long x 6" wide because they only had 60" pieces in the rack , and I didn't know what I might be building in the future. You can make it any size you want.
The end plates I made from 1/4"(stuff laying around), and milled slots in them so I could slide the jig to one side or the other for balance. If you have any questions or if I can help you in any way , get in touch with me.