37 replies to this topic

[masakari098]

I took apart a bunch of old hard drives for their magnets for a project i'm working on. problem is, they are glued (epoxy, i think) to the mounting bracket for the read head. does anyone know how to get the glue off? i'm thinking of bathing them in acetone, but i'm up for any bright ideas

[replax]

to do this you must construct one of the wold's largest electromagnets. you need 12 miles of 30 guage wire, and a 530lb iron rod 8" in diameter. you will also need at least 40kw of electricity, which you can only get from an industrial power connection(most homes don't give 30)

but seriously, i have no idea, i can only direct you to the short list of solvents
1 Water
2 Rubbing Alcohol
3 Gasoline
4 Turpentine
5 Acetone
6 MethylEthylKetone
7 Formaldehyde

if one of those can't get rid of it, you need to use an acid


i have never tried to take the bracket off, damn thing would be impossible to take off a piece of steel without it.

Edited by replax, 12 May 2004 - 07:59 PM.

[Subzero1037]

i broke some magnets with a screwdriver trying it..... i don't know tho....

[mausa]

are those magnets any good? I mean are they strong?

[replax]

super strong, stongest i've seen, next to those neodynium rare earth magnets

[Subzero1037]

yeah dude they are impressive.... if i put one on each side of my hand it'd have enough magnitization through my hand to stay there...

[neuro]

i used to have some magnets that came off of the alternator of a power-generation wind turbine, and those where uber-strong. The hard drive magnets are possibly the best at practical disposal.

[White_Raven]

This seems like a interesting project; Does anyone know what the bonding agent is made of? It seems to me if we knew that it would be much easyer to deal with it.

[replax]

i don't know
if i had to guess i would say it's a resin glue, i don't think it's an epoxy, if it is an epoxy it would have to be a real soupy runny mix, it doesn't build up a miniscus at the edge of the magnet. but seriously, if you ever got it near somehting iron,it would be damn near impossible to take off. what are you buliding that you need magnets like that for? trying to undo the chainlock on someone's door?

[masakari098]

lol....nothing like that. i'm actually trying out a design for a homemade generator i found on the net. i need the magnets separated from their brackets because they are going to be mounted to what amounts to a timing wheel. one website suggested i freexe the magnets. i put them in my freezer, but i dont think that's cold enough. i'm going to find a can of compressed air and see if that does the trick. also, i found a place that said methylene chloride can dissolve it, however, it also said it's sort of hard to come by, because it's a carcinogen. the most direct and proven way, baking, isnt even open to me because the heat would neutralize the magnets. i do know that two sets of the magnets came off rather easily because the glue was brittle. that looked alot like epoxy to me. anyone's guess what they used on the other ones

Edited by masakari098, 13 May 2004 - 10:08 PM.

[replax]

if it is epoxy, there's a name brand of stuff called "attack", may be able to find it at home depot. it sometimes takes a while but it is an epoxy solvent.

[White_Raven]

A while back (years ago) I designed a generator of my own, my problem was I did not have powerful enough magnetic field generated to keep the alignment of the force acting on its core assembly; Does anyone know the EM field rating on these magnets?

It would be interesting if you could get them bigger as well.. and possibly shaped.

Either way, it would be interesting to find out the chemical components of the glue keeping the magnet in its place; A little rouge chemistry may even allow us a easy way to get them from old hard drives.

[replax]

look into neodynium rare earth magnets, you can get them in shapes and they are just about the strongest magnets you can get. not really that expensive either

[paul1701a]

Try soaking in Muriatic Acid. You can get it fairly easily its used to clean masonary.

[replax]

the definition of an acid is something that releases hydrogen gas when it reacts with a metal

putting metal magnets in an acid is not a good idea, depending on the molarity. but it will eat the metal away.

[White_Raven]

the definition of an acid is something that releases hydrogen gas when it reacts with a metal

putting metal magnets in an acid is not a good idea, depending on the molarity. but it will eat the metal away.

Exactly my point, knowing the exact chemical compounds could allow us to hack something up to allow us to target the adhesive directly rather then to resort to brute force.

[replax]

yes, if we know what it was it would be so much easier. i say leave it in gasoline for a week, there are so many complex organic compounds in there that it'll eat through anything organic.

[jedibebop]

My friend put his hdd in muratic acid for like a week, it ate off the case, the discs and magnets and shit were still there for a while

[ilpimp]

i just used a screw driver to rip the magnet off when i took one apart