Precision Spin Top / Polished Bronze over Aluminum - $57 - (Alamosa, CO)

Here is a precision spin top that I made out of bronze and 7075 aluminum on a manual lathe and mill. The bronze is polished to a mirror finish. The stem is faceted, having 12 flats milled around an 8 degree taper. The contact point is an 1/8" Si3N4 ceramic ball for long life and smooth spins. I timed a few spins on a concave mirror, and the longest time I got was 11.05 . Spin times will vary from person to person. The diameter is about 1 1/16" , it is about 1 1/4" tall and it weighs 37 grams. A black velvet carry bag is included.

Posted in Alamosa, CO, Toys & Games
From ebay.com - 1 month ago