A thumb turn knob for M8 bolts and nuts. Easy to turn and really strong.
The bolt or nut is a satisfying press fit from the top. Screw together to seat them properly and they can still be removed.
I printed this in PETG for its toughness and for my particular application.
The print profile is slow for PETG quality. 4x 0.5mm walls and 20% 3D Honeycomb infill give it strength. The subtle 0.1/0.1 fuzzy skin texture gives it that professional look and feel. No supports are needed.