Ceiling ring hook (detachable)

thingiverse

The original ceiling hook could slide out of the base, which made me feel uneasy. I wanted to hang my body weight from them without worrying about this risk. I started over from scratch in FreeCad and experimented with different solutions. This final design turned out to be the strongest one yet. It features a locking cover that prevents the base from opening up and getting subjected to shear forces. The locking top cover can slide onto the hook, then rotate 90 degrees. Because of its asymmetrical shape, the hole in the cover makes it impossible for the ring to go over once rotated, thus acting as a safety lock. I printed this design in PETG with 5mm wall thickness, 3mm top and bottom thickness, and 50% gyroid infill. To achieve maximum strength, I printed the ring on its side to prevent layer separation from affecting its integrity. High temperature and low fan speed also contribute to added strength. Now, I can hang my full body weight from these with complete confidence! I've even used them for grip training and pull-up balls. WARNING: do not use these for rock climbing or any situation where failure would be hazardous. Remember, it's a 3D printed part – don't put your trust in it.