Magnet Pole Utility

A quick little utility that might seem obvious and innocuous, but is incredibly useful. I keep this at my maker workstation to identity poles for magnets typically used in 3D printing. I used the traditional colors of red for north and blue for south, but of course you can make it any colors you'd like it to be. Simply place an unmarked magnet on it to know which poles are which. Opposite poles attract each other, so:

• A magnet's south pole “sticks” to the N face
• A magnet's north pole “sticks” to the S face

Uses one 20x3 mm magnet embedded inside the tester. The print pauses so you can insert the magnet.

How do you tell which pole is which if you don't have the tester? Good question! Here's a VERY simple method:

You'll need:

• Tape
• 20x3 mm magnet
• Thread (not string or anything heavier than thread)

1. Cut a piece of thread about a foot long
2. Tape the thread to one side of the magnet
3. Hold the top of the thread, letting the magnet dangle at the end
4. The magnet will rotate but eventually will come to a rest
5. The north pole of the magnet will face north; the south pole will face south (you can use your phone's compass app to verify)
6. Use a marker to indicate which side is which

Have fun!

NOTE: I don't own an MMU3, so I guessed on the 3MF configuration. Please check the setup before you print!