Could this be for a mancala board?https://www.smithsonianstore.com/product
/african-stone-game-68558.do?code=N2ISGPLA&gclid=Cj0KCQjwvr6EBhDOARIsAPpqUPHdP_n
pf8XSr8dTwVJoGh5Ql6emUWsKgimR5xqO3IA6M75pt0aKa70aAqS1EALw_wcB&gclsrc=aw.dsLoose
sanding grits are easily available on the interweb.  If it is critical to make a
sanding device to sand a half sphere, my initial though is to glue up some thick
leather around a spindle, and shape the leather to fit in the half sphere. As
long as the width and profile are correct, then the thickness could be less than
the diameter of the sphere. Charge the edge if the leather sander with some
loose grit and maybe some.wax to help hold it in place,  and Bob might be your
uncle. Or maybe not. I have never actually tried anything like this myself, so
my initial thought could be way off base (totally wrong Jeff).David SobelSent
from my Galaxy
-------- Original message --------From: scottg  Date: 5/3/21  6:45
PM  (GMT-05:00) To: oldtools@g... Subject: Re: [oldtools] home made sanding
compound? Patiently waiting for the other shoe to drop.   Why is it we need to
work on the inside of a sphere? What sphere?    What element is it made of, and
why?  How big is it?How big of an entry hole is allowed?  Or can it simply be
turned in 1/2's and put together?If you can open it up, then a scraper ground
out for the occasion and used on the lathe is going to be fastest.    yours
scott-- *******************************    Scott Grandstaff    Box 409 Happy
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