In 1959 I was in Hong Kong and bought an Ivory chess set that had all of the pieces set atop Chinese concentric balls. I purchased it at the exchange here, but had to go to the factory to pick it up. When I got to the shop I was invited to go into the shop and see them being made. The shop turned out to be the basement which was crowded and rather dimly lit. The balls were being turned by thin (poorly nourished) men in under shirts and baggy pants on peddle operated lathes. The lathes were driven by a leather string looped over a short length of bamboo which was about 4" in diameter. The ball rotated in one direction on the downstroke of one pedal and then reversed rotation on the downstroke of the other.
The turning tools were fashioned from small triangular files, the tangs of which had been bent and then ground. They cut in both directions.
I know, Ivory cuts differently than hard wood, but If I were to try this myself, I would probably go with scrapers that I made myself.
Unfortunately this chess set sat in Katrina's flood waters for a couple of weeks and emerged a uckey brown. Some to the balls cracked and a few were lost. The remnants now reside in a box some where in a closet somewhere in this house.
