So I finally got the wrist done. And aside from grinding off welds on bolts and backing off the bolts to allow for free movement at joints, I'm mostly going to try to keep this skeleton stock for the most part. So I may be attaching the hand and going immediately into electronics rather than fiddling with the skeleton adding more range of motion here and there. I can always add that later anyways. And in fact the poseable joints that are fairly stiff I'm finding is actually pretty convenient while working on it so I may only free joints on an as needed basis for testing electronic actuation of that joint. Until then I'll leave them alone.

Also note: I was planning to have the wrist rotate axially around the location of the wrist for the pronation and supination. However, I realized this will not look right since you can visibly see the forearms move and the muscles there moving when you pronate and supinate your arm. So I have to have the pronation and supination be where the skeleton was originally doing this near the elbow. This will allow for much more natural looking pronation and supination. So the wrist location will not rotate AT ALL after all. This made it all the easier to make the ulna and radius distal wrist joint where the little wrist bones and hand will attach to and rotate on. I sculpted it all in fiberglass and super glue with some nails and some ABS plastic pieces and epoxy to build up the shape. I used my ABS 3d print of this part as reference only. This thing needed to be very strong as it's likely going to the point of failure as the rest of the arm is steel. So I wanted to make sure it was maximally solid and didn't fully trust just going with a 3d print there.