With both faces as reference, I machined the mating pivot faces flat. You can use a mill or even your lathe by making a temporary jig to hold it vertical and positioning correctly on your cross slide. With that done, it's a simple matter to clamp the halves together and drill through the guide holes in the parts at the same time. This ensures absolute alignment. The dimensions for the pivot are included in the detailed part drawings included with the kit. You could make the pivot pin out of Air or Oil hardening steel but I found plain old mild steel works fine. Again, your choice. The screw is a stainless steel hex head cap screw 6-32 by .5 inch long. All the finger clamp screws are the same so that one Allen key adjusts everything.
|Inserting the steel pivot pin|
I've made brass fillet washers for the pivot screw and for all the finger clamp screws as well. I like the addition of the brass with the bronze/stainless color and they spread out the stresses. You can design whatever you'd like here. I chose to make the fillet washer .175 thick for easy finger access to the clamp screw to spin it on and off once its loosened.
|View of the pivot pin slightly recessed from back surface with screw and fillet washer|
|Top securing screw and fillet washer in place|
|Frame top pivoted open|