This is a simple magnetic cup to hold screws.
The round magnet is 12mm in diameter and 4mm thick
The hole in the model is 13mm in diameter and hole is 5mm deep so there is a little headroom
Printed at 0.34 for quicker print time
I stuck in the magnets with super glue. Seems to work well
What I tried
I originally designed it with 1 and 2 magnets but wouldn't catch most of the screws on the side I tried having the magnets just clip in with some force but they ended up either coming out when attaching them on to metal or become loose inside causing inconsistent magnetism... I also tried reducing the thickness between the magnet and the top surface area, but ended up being to thin. I hollowed out the bottom to save on filament and printing time Made thinner walls, as it uses less filament and is quicker to print I also added a bit of space between the bottom of the magnet and the bottom of the print instead of making it flush. This made it easier to remove the cup from metal objects.