The knuckles on the bottom Pbox lid are a separate, soldered on plate like the knuckles on the vertically mounted plate. The top pic shows the soldered on lid knuckle plate. At least the separate knuckle plate enables one to discard it w/o throwing the lid away. All the brass pieces of the Pbox are annealed. I use a soldered on lid hinge plate that's .040 thick as is the vertically mounted hinge plate....the top of the knuckles protrude slightly above the lid.
I use a 1/16" thick steel plate w/ a 1/32 radius that matches the steel 1/16 dia hinge pin that's a length of music wire and that's long enough to accommodate all the knuckles when forming the "U" shape which are then formed into knuckles in the vise w/ a 1/4" steel backup plate so the knuckles don't bend backwards. The length of the ends that form the knuckles is determined by a test strip and I use a piece of hard maple to completely form the knuckles. The vertically mounted hinge plate is made the same way. When mating the hinge plates, relief for the knuckles has to be filed just enough so the hinge pin enters all the way. Doing it as explained will automatically line the hinge plates. Doing the work is easier than explaining how to do itanyways for me.
For Pboxes that have a curved hinge, soft baling wire is used for the hinge pin.
The middle pic shows the easiest way to make the knuckles when the "U" shape is formed and the hinge pin is up against the radius of the "U" and the brass is squeezed in a vise to form the knuckles. The one shown has the tabs riveted but they could also be soldered. I prefer the other way of doing it.
YIP....I take it that the only thing that's yet to be done on your Pbox is filing clearance for the knuckles so the hinge pin can be pushed in? Also, don't forget the draft on the sides of the knuckles. Looking good so far....Fred
