Gordon,
I've not turned buckeye and will be interested in other's experience, but you should ask your friend if he can wait until the tree is dormant to cut it. I don't know where you live; here along the Northern tier of Missouri, that would be mid to late November through February. The "sap is down" and will give you a head start on drying as well as a good chance that the bark will stay on natural edge turnings. It may be an illusion, but it seems to me that live trees I've cut in winter are more stable than summer-cuts.
I'd wish you good luck, but it sounds as if you've already got some.