Summary

I designed this from the bottom up because it's dead simple but Captaingrey inspired this way of doing it.

They're 1.5" in diameter for extra beef factor.

I know part of the original point was that it wasn't using wing nuts but I liked the "knob" tightening that was more ergonomic, so this is the best of both worlds. I put a drip a CA glue on the wingnut to hold it securely to the knob.