A simple magnet hook to hang up things on metal ceilings. This is for (neodymium) magnets with a diameter of 11.4 mm and a height of 2.8 mm, a size i had lying around. This size can be changed somewhat easily in FreeCAD, in the “sizes” spreadsheet.

Stop the print before the first top layer is printed and insert the magnet. Make sure that

• it is in low enough so that it doesn’t colide with the nozzle
• it is in tight enough so that it won’t leap up and stick to the extruder carrier. (That happened to me with another design.)

Anyway, tie some twine to the loop and hang up your thing. I use it for a “ceiling” light on my balcony.