Slashdot Mirror

Have you ever tried to erase data from a hard drive with a magnet? There's a reason physical destruction is often used when high security is required. There are commercial degaussers available, but playing music on a loudspeaker isn't going to do a thing.

And if it takes a specially prepared slurry (presumably made in an old Luddite factory, eh?) to make the magnet, doesn't that kind of defeat the purpose of 3D printing?

But let's not let that little detail get in the way of a good 3D auto-fellation,eh?

And do you think rare-earth magnets just go full strength magically? How do you print something with such a powerful field when there's all this "3D printer" stuff (made of metal I guess) moving around? Hmm?

Oh wait, rare-earth magnets need to be activated! But hey, that little detail is glossed over and let's just ignore that little bump in the road!

Let's look at how the Luddites do it:

https://www.kjmagnetics.com/bl...

Oh, "They are placed in a fixture that will expose the magnet to a very strong magnetic field for a brief moment. It's basically a big coil of wire surrounding the magnet(s). The magnetizing equipment uses banks of capacitors and a really huge voltage to get such a strong current for a brief instant."

But 3D printing is magic, I guess we can skip such inconvenient things. Maybe you can 3D print a neutron star and use its magnetic field and then put the neutron star in a 3D unprinter when we're done with it?

And printing transistors? That's so far away from anything that's even remotely possible, I'm speechless.

Do you have any inkling of a clue of the material purity required and cleanliness and precision required? Jesus Christ!

Check it out, someone buys a power transistor from Digi-Key, and a stepper motor places it on a blob of plastic. That's all it takes for you nutcases to run around thinking it's a revolution.

This is nuts. Uncritical, unthinking 3D cheer-leading.

Is an electromagnetic coil in the door frame an realistic idea?

While it was a cool trick in Cryptonomicon, the reality is that you'd probably rip the drives out of the person's hand before you actually managed to erase it. It's pretty hard to do from outside the case.

Or K&J Magnetics, which (as you might guess from the name) just sells magnets. They provide detailed product specs along with explanations of the terms used.

Or K&J Magnetics, which (as you might guess from the name) just sells magnets. They provide detailed product specs along with explanations of the terms used.

Those are my two favorite types of toys.
For magnets, I like K&J Magnetics.
For flashlights, I've ordered but not yet received some seriously bright small flashlights from Fenix.
Lasers are a subclass of flashlights to me, and you already have that covered.

Large Neodymium magnets are ridiculously dangerous, but don't underestimate the small ones, either. A small one I had (1cm x 1cm x 2mm) flew with such force at a metal surface that it shattered upon impact.
I've also had the misfortune of pinching flesh between 2 8cm cube magnets, and the only way I could get them apart was to anchor one on a metal filing cabinet, the other on a pair of pliers, and then pull the pliers away from the cabinet (Note: Getting skin caught between two neodymium magnets is one of the big No-Nos). I have no desire of ever having a larger one like the inch cube 3770 has, simply because of the safety and responsibility (or injury) that goes along with having one... although it would be pretty nifty to hang a bike from one.

Despite this, they are pretty neat, if not just because they kick the ass of wussy refrigerator magnets. thinkgeek offers a package with assorted small neodymium magnets, as does k&j magnets, who I ordered mine from back before thinkgeek picked them up.

Being good open-source citizen, you will immediately donate that $100 gift to your favorite OSS project! Thank you! Or Maybe just a few bucks.

Or, you can buy a bunch of little stuff, like:

Super-strong neodymium magnets. Magnets sound boring, but these things are really, really strong. Get the spherical ones.

There's a whole host of cheap, unusual geeky projects at American Science & Surplus.

Get a cheap computer. Buy a Used Xbox, and install Xbox Linux on it.

Color changing lights. The color change is nice and smooth. Popular with the kids.