This is a derivative of the excellent Do-Nothing Machine by RayRaywasHere. I could not seem to list this thing as a version of RayRaywasHere. So I just went and listed it as new. This is not a new thing. This is my version of http://www.thingiverse.com/thing:5103.

I removed the pin in the shuttle and replaced it with a hole for the Pin/Rivet I designed.

I made the arm holes larger to acomdate the rivets.

The base is unchanged from the original and was a pleasure for me to both print, and test.

Print 1 base Print 1 arm Print 2 Shuttles Print 2 pins.

I printed 6 pins at once, this allowed for cooling of such a small shaft. It also gave me a reason to make more than one Do-Nothing.

Clean up the base and shuttle with knife, file, sandpaper.
Place one shuttle in the base, and pin the arm to it with one of the rivets. Place the second shuttle in the base, and pin the second arm home to the shuttle.