Wednesday June 17, Aiguines, France

Another day of woodturning. We were back at it at 8 am. With our newly turned perfect spheres, we began to turn them into Chinese balls, a sphere with concentric spheres inside it. Basically this just takes special tools. Yesterday we made our own jigs for turning our spheres. Today we just used the tools from the instructor and school. First you need a sphere chuck. This holds the sphere while it is turned. You need to be able to hold the sphere securely, and then rotate it to one of the other dodecahedron points. Jean-Claude had homemade chucks made from glued up plywood, that were threaded to tighten them. Simply unscrew the holding ring a little bit and you could rotate the sphere inside. Then you need a special set of tools to undercut each of the other layers. Plus something to hold those tools. Jean-Claude designed a flat tool-holder and a flat table-like tool rest. Together they hold the tool perfectly level and allow you to make your cuts.
You mount your sphere in the chuck, and then align one of your dodecahedron points up with the exact center of rotation. No easy task. The first tool, a triangular pointed tool, goes in the tool holder, and a triangular hole is cut in your sphere. When done take that tool out of the tool holder, and put in the first knife to undercut the innermost sphere. This is the easy part, takes about 3 seconds. Repeat for the next four tools, and you end up with your first point done. It is sanded, and then plugged with styrofoam, to hold them in place while the other points are turned.
Untighten the chuck, rotate your sphere, align the point, and repeat the turning for that hole. This is done twelve times. I managed to finish a 5 sphere Chinese ball by lunchtime, using the sphere I  had turned myself from sycamore. After lunch Jean Claude presented us with some boxwood spheres that are turned perfectly with the aside of a sphere jig. Boxwood is a premier turning wood, and a joy to turn. Jean claude suggested I try a seven layer ball. So I spent all afternoon doing that. And I must say it came out alright.
So goodnight for another day. God bless you all.