Whether you need a handy tool to keep your screws and nails in place, or a sweet gesture to show your affection, this ring of attraction is for you.

This model is designed to fit a small magnet in the center of the ring, which can then of course hold various metal items. You can print multiple rings and wear them on different fingers, depending on how much space you need. You can also print two rings with matching (opposite) magnet poles outwards and give one to your partner or best friend. The rings will snap together when they are close, creating a magnetic bond.

Sizes

This comes in two different magnet sizes, 10x2 mm or 12x2mm. I picked these two sizes because they're quite common and arn't too tiny to be useful on the finger. You can get such magnets readily on Amazon/Aliexpress/etc. If you want to customize for another size, I provide a parametric Fusion360 file that's easy to customize.

You can choose from different ring sizes, from 4 to 13.5 (see standard ring size chart below).You can either measure your ring size ahead of time, or just print several ring sizes around your best guess to find what fits. For reference my wedding ring size was 8.5 (18.5 mm) and I found that a size 8.5 or 9 fit me from this model when printed in TPU.

Note: Tolerance for the magnet to fit in a TPU-printed ring is already built into the model.

Printing

I recommend printing in TPU or similar flexible filament, but hard filaments like PLA/PETG can also work if you pick the right size. The ring prints fine at 0.2 mm layer thickness in TPU.

Assembly

Simply put a small bit of super glue in the magnet hole and press the magnet in place to keep it attached to the ring. You're done !

If you want to make a matching pair of rings, make sure that you align the magnet poles so they'll stick together before you glue them in place (you can mark them w/ a marker if you want).

Customization

The key parameters in the Fusion360 file to tweak are Ring size and Magnet size/thickness. Ring size (diameter) can be adjusted simply by changing the ringID parameter, and magnet size is easily adjusted by changing actualMagDia and magThickness values.