Need a Tool!

I am currently beginning a build for a miniature steam engine called "Baldy", which uses a ball for a piston. I figured a ball-turning attachment would be handy, and that's how I found this site.

Most of what I do is building odd parts for unrepairable items, and always think of more projects that I can possibly do.

As a newbie, it's probably me: Why do the plan links not work for me "Error 404, etc b.s." ??

Please post a link that you're having trouble with, and then I'll take a look.