The idea is simple. I used composition metal as it's easier to cure.
With the 2nd drill size 4 I did 3mm holes so the edges are wider and the mounting ring won't decelerate. Then I cured everything on the rasp and polished on grindstone. After that I added 2 rings and a hook.
Teachers! Did you use this instructable in your classroom?
Add a Teacher Note to share how you incorporated it into your lesson.