Magnetic Key Chain

There are two things unique about this key chain. The first thing is simple, but the second thing is more unique. Let’s start with the first thing: It is is magnetic. But what’s more interesting is the process of how the magnet is embedded. I’ll show you how this process works and the clever trick I used to help embed the magnet. 

The key chain is designed with an internal cavity. This cavity can only be accessed while the key chain is printing. It prints layer by layer from the ground up. You would think that it would be easy to pause the print and insert the magnet mid-print. However, because the extruder, the part that extrudes the plastic, is metal, the magnet will not rest in the cavity. It gets magnetized to the extruder! Also, pausing the print could ruin the surface quality. 

Here’s where my clever solution comes in. Instead of just 3d printing the key chain, I 3d print the key chain with what I call a “timing tower”. The timing tower changes shape when it’s time to embed the magnet. It is also strategically placed so that when the 3d printer is printing the tower, the key chain is pushed forward, making it easy to access. Then I can add a glob of hot glue and place the magnet in the cavity. The print never has to stop, I know exactly when to place the magnet, and it move the part forward so it’s easily accessible.

And that’s how you can easily embed magnets into your 3d print. Also, this magnetic key chain is pretty cool.

Print settings:

0.4mm nozzle

0.28mm layer height

50mm/s print speed

20% infill