Bypassing padlock with magnet

[cnidocyte]

I have some rare earth magnets that are so strong they would crush your fingers if they got between the poles. I haven't tested this out but I don't see why they couldn't retract the latch of a padlock. Anyone here tried this?

[weilawei]

Unless it was magnetized itself, you would need to use electromagnetic levitation most likely.

See [url]http://en.wikipedia.org/wiki/Magnetic_levitation#Induced_currents.2Feddy_currents[url]. I think that, in theory, this is possible. However, you may wind up with significant difficulties owing to the potential conductivity of the surrounding materials, as well as the magnetic properties of the latch itself.

http://en.wikipedia.org/wiki/Permeability_(electromagnetism)

I'm just going out on a limb here, but I do think it would be possible with a very strong electromagnet (*if* you could induce a field strong enough). Also, electromagnets are super-cheap and easy to build--might be worth testing it!

[raimundo]

You mean it can pull back the brass locking dogs? thats some strong magnet

[weilawei]

It would have to be a ferromagnetic material, I imagine. Wouldn't work on everything. I have a Master Lock here that looks like it uses a steel locking dog. That, or it's chrome plated.

[weilawei]

Additionally, brass is diamagnetic--even then, it may be possible: http://www.physics.ucla.edu/marty/diamag/.

[cnidocyte]

Ah right, I thought the locking dogs were made of steel. The magnets I have would definitely retract a locking dog with iron in it but theres not much they can do with brass.

[Ortin468]

The lock would have to be one that could be shimmed in the first place.