Magnetic race bib holder (ferma numero di gara magnetico per ciclismo)

thingiverse

This is the simplest and fastest way to put your race number on your shirt or jacket. With four magnetic bib holders, you can attach your number bib without using safety pins. You need eight magnets of ten millimeters in diameter and two millimeters in thickness (they are easily found on Amazon). It's necessary to print four magnetic bib holders and stop the printing at the 15th layer with Cura 4.6 at sixty-five percent of the print, insert a drop of instant glue under the magnet (the magnet tends to adhere to the printer extruder), insert it in the hole and then restart printing. At this point, just insert the other four magnets inside the shirt and fix the race number. Enjoy!