I want a jig that will allow me to make a near perfect wooden ball on my lathe. It should range from 5 inches DIA down to near nothing.
Here it is on SketchUp.
The lighter color "S" curve in the background mounts to my carriage on the right. It has a pivot at the bolt on the left. This pivot supports the blueish "S" curve as it rotates around the ball. The cutter is in it's usual tool holder, then mounted via the white slab. The four bolts holding the cutter assembly will probably have a small plate near the heads. The atom looking part is just the possible ball that will be turned. The left side of the pic is my headstock that holds the blank wood.
My challenge was to get the "S" curves built in wood. I choses to turn a cylinder of the correct dimensions.
...then cut it up into 1/4 arcs
...to be glued onto the ends of plywood.
Then the whole assembly will be glued together. It's a pity that the arcs weren't cut accurately, but I'll fill in the gap with papertowel and wood glue.