On the 4 X 1 1/2" channels, mark and drill 5/16" holes, 1/2" from the outer corners...Clean edges. These will now be referred to as "Hinge Blocks".
On the 6 X 1 1/2" angle pieces, mark out and drill (see diagram), first the attachment points (using 3/16" bit), then pivot points (using 5/16" bit). These will be called "Hinges"…Note that the hinge in this photo has not had its end rounded, but it is scribed….
Drill corresponding holes for attachment points on 3 of the Hinge blocks, using 3/16” drill. (The hinges should be 2 3/16” inches apart.) Countersink these holes on the inside of Hinge Blocks.
On fourth Hinge block, drill holes corresponding to the angle bracket...Bracket should be flush with the top of the Hinge Block. Countersink interior holes, and bolt Angle Bracket to Hinge block, using #10 screws/lockwashers/nuts.
Attach Hinges to Hinge blocks, using the #10 screws, lockwashers, and nuts...
On the assembled Joint, insert bearings in one side (top and bottom). Place between Hinges, then through-bolt using 3" X 5/16" bolt--The bolt should go through things in this order: washer, top Hinge, 1 more washer, Joint assembly (with bearings), one more washer, bottom Hinge, washer, Nylon 5/16" locknut.
Repeat this with another Hinge block, on the other end of the Joint assembly.
Now, using the other 2 Hinge Blocks and 4 Bones, assemble arms: IMPORTANT!!! holes for eyelets should be in marked locations...Using 8 X 2" X 5/16" bolts, bolt Bones to Hinge Blocks...Similar to Joint assembly, the bolts should go through in this order: Washer, Hinge Block, 2 more washers, Bone assembly (with Bearings), 1 more washer, Hinge Block (other side), washer, Nylon Locknut.
