A while ago, [Gord] received a notice from his daughter’s school looking for silent auction donations for a fundraiser. It’s pretty much a bake sale, only [Gord] gets to build something. He has a pretty nice machine shop, and eventually settled on building a pair of beautiful vacillating vertical pendulums. They’re yo-yos, in case you were wondering what that meant.

Each half is cut out of a 2.5″, with both sides of each half faced off and tapped. From there, eighteen speed holes shave off 22 grams of weight. The sides of the yo-yo are shaved down to a thickness of half an inch, a 14° bevel is put on each face, the edges are chamfered at 30°, and everything is polished up.

Sending a bare metal yo-yo to a raffle is apparently a little uncouth, so [Gord] anodized each half of the yo-yos in a bath of sulfuric acid, then applied dye to the surface. With everything assembled, a fancy glass and metal case was constructed and a certificate of authenticity printed out. It’s a brilliant final touch to a great project, we just wish we knew how the yo-yo performed.

Thanks [Chris] for sending this in.