Having got down to the carpal assembly in the hand I was left with having to design the interconnection between the carpals and the radius and ulna. I decided to see if I could put together a workable ball and socket joint within the size constraints that I am working with.
It turns out that I can...
I made the ball in two parts to avoid having to use support material and used a recessed machine screw to connect them.
I will need to tighten up the collar a bit to insure that the ball isn't too lose in the socket.
One thing that has occurred to me is that I can design the collar orifice of the socket to restrict the movement options of the joint.
Now I'm wondering if I could design a more compact, more biomemetic knuckle joint?