Star-shaped thumbscrew head for hex bolt

thingiverse

This is a head to turn a regular hex bolt into a thumbscrew, easy to tighten and loosen by hand. The regular version is flush with the screw head; another "pole" model extends a bit away from the screw. This makes it easier to grab the handle when the screw is fully tightened, but may reduce rigidity a bit. I recommend high infill (I used 50%) and high number of perimeters (I used 6) to ensure rigidity.