Furnished content.
(from Lumberjocks.com)
My only regret with this project is that I didn't think of it first. Gotta give credit to Oliveir Gomis. Stumbled upon his https://www.youtube.com/watch?v=_pDTXd8wZ80 and was determined to have one for myself. My first sphere was a fail (we'll call it a practice piece) but I learned from it and the second time around was much better. And since my tools were inferior to his, (old craftsman 12” lathe) I was forced to come up with a different method to make the dish. For that I made a jig/sled for my angle grinder. Mounted a long threaded rod to center of disc so that I could spin it to raise higher as I dug out the center. Roughed it with an arbortech turbo plane disc and finished with sanding disc, then fine finished sanded with ros.Didn't have any dimensions so I had to guess. Looks like my size ratio between ball/dish varies from his. My sphere is 5” dia. and dish is 19” dia. here's minehttps://www.youtube.com/watch?v=myrST41Rci4