I used the core of a toilet roll to make a cylinder and half a styrofoam sphere to make the bottom end.
I quickly put my hand on two empty toilet roll cores, then found a couple of ball joints, one wooden, and the other a plastic knob. It turns out that the toilet roll core was exactly the same length as the upper leg on my working drawing. I cut a pie-shaped slice out of the cylinder, taped it up with clear packing tape, trimmed the ends with scissors, then I added the balls to each end with some small pieces of clear tape. Finally I melted some wax around the joins. I'm planning to make a quick plaster mold of this piece, then cast two upper legs in wax. After that I can model the leg shapes in wax.
The little fellow showing off the upper leg (below) is an elastic-strung wooden Pinocchio doll, 7-1/2 inches tall. He really isn't a ball-joint doll because he doesn't have sockets for the joints. The legs are screwed together and the elastic loops around the screw, so it can stand and sit. The legs and arms are made from one piece of wood each, with no joints except at the top. He's a cute little fellow, made in Italy.
Pinocchio, an empty toilet roll core, and the rough upper leg (View No.1).
Pinocchio, an empty toilet roll core, and the rough upper leg (View No.2).
Pinocchio, an empty toilet roll core, and the rough upper leg (View No.3).
I still have to make the lower leg, but I'm going to do it with cereal box cardboard profiles.
This work is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported License.