switchable magnet

2 Articles

You Can 3D Print Yourself Some Simple Magnetic Switches

August 22, 2024 by 9 Comments

Permanent magnets aren’t typically switchable. They’re always doing their magnet thing. However, if you align them with a bunch of other magnets in just the right way, you can create a permanent magnet that you can effectively switch on and off. [Andrew Klein] has done just that with his 3D-printed magnetic switch design.

The concept is simple enough. The design consists of a 3D-printed housing in two parts, top and bottom. When set into one orientation, the housing holds two arrays of magnets in opposite orientations. This effectively cancels out their magnetic fields and allows you to move the assembly around as if it’s pretty much not magnetic at all. However, rotate the device to its alternative orientation, and the magnets poles are aligned. This effectively combines their magnetic fields and makes the assembly act as one big large magnet.

These devices are useful if you want to create magnetic clamps or fixtures that can be attached and detached at will from ferrous surfaces. Being able to effectively “switch the magnet off” is much easier than trying to wrench a powerful magnet from a metal plate, after all.

You can do something similar with electromagnetic techniques, too! Video after the break.

Continue reading “You Can 3D Print Yourself Some Simple Magnetic Switches” →

Toggle Magnet

Switchable Magnet With A Simple Circuit

March 17, 2015 by 26 Comments

Magnets are awesome. Electromagnets are even cooler. But what if you could make a semi-permanent switchable magnet that acts like an electromagnet, but doesn’t use any energy to hold metal? You’re going to want to take a look at this Low-power Magnetic Hold and Release Mechanism.

It’s actually a very simple concept. It is basically an electromagnet attached to a permanent magnet — it’ll hold any metal object exactly as you’d expect — but if you run current through the inductor attached to it, the magnetic field created by the electricity will temporarily cancel out the field of the magnet — thus freeing your object being held. Since gravity is pretty fast acting, this impulse of current doesn’t need to be very long, only fractions of a second.

Now the real question is how big could you go? We covered another project a while ago called Open Grab which discusses the possibility of using technology like this in Quadcopters.

For a solution that uses no power at all take a look at switchable magnet clamps used for welding — they’re pretty cool — but patent protected of course.