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[Levi]

I am wanting to make an electromagnet for a project, but have run into a minor roadblock.  Everything that I've read says that an iron core is the best material to use when making an electromagnet, so I figure I'd try to find some iron bolts or nails or something in some hardware stores.

Turns out most things are made out of galvanized steel or Zinc these days!  Does anybody know where I might find some iron that I can use as a core for an electromagnet? 

[Shook]

Steel is pretty much iron with carbon, and the galvanizing won't hurt the magnetism (i think, test with a magnet). Pure zinc won't work, but unless the zinc layer on top of the steel is superconductive, it won't stop your escapades.
So yeah, if pure iron isn't readily available, galvanized steel SHOULD be fine. I may be repeating myself here, but if an ordinary magnet grabs hold of it, you're good to go. The difference is far from overwhelming.

[MonkeyHead]

I reccomend magnetically soft iron, to avoid turning your electromagents core into a permanent magnet...

[Frelock]

Go and find out if you have any black sands nearby.  You can use a magnet to pick up the magnetite in the sands.  You'll probably have to repeat picking it up with a magnet, preferably underwater, to ensure you get a good chunk of the impurities out.  Then, build a bloomery (the most primitive type of smelter) to get your iron.

Or you could go to a scrap yard and try a magnet.  Or see if anyone would sell you some wrought iron (which has a very low carbon content).  Honestly, if it's magnetic, it'll work.

[nenjin]

Try and get some iron oxide powder, maybe through online ordering? I know some companies press the stuff into cores.

[ChairmanPoo]

The problem with steel, as has been said, is that it remains permanently magnetized. Hence, if you're making anything that relies on the electromagnet demagnetizing afterwards (IE: a doorbell) it wont work.

[Levi]

Steel is pretty much iron with carbon, and the galvanizing won't hurt the magnetism (i think, test with a magnet). Pure zinc won't work, but unless the zinc layer on top of the steel is superconductive, it won't stop your escapades.
So yeah, if pure iron isn't readily available, galvanized steel SHOULD be fine. I may be repeating myself here, but if an ordinary magnet grabs hold of it, you're good to go. The difference is far from overwhelming.

I've read that galvanized steel doesn't work well in electromagnets, but for all I know it might not make a big difference.

Go and find out if you have any black sands nearby.  You can use a magnet to pick up the magnetite in the sands.  You'll probably have to repeat picking it up with a magnet, preferably underwater, to ensure you get a good chunk of the impurities out.  Then, build a bloomery (the most primitive type of smelter) to get your iron.

I should stress that I'm fairly incompetent at most things, and that is way beyond me.  Also I don't think it would fit in my apartment.   

Try and get some iron oxide powder, maybe through online ordering? I know some companies press the stuff into cores.

That sounds promising.  I'll look around a bit for that.

The problem with steel, as has been said, is that it remains permanently magnetized. Hence, if you're making anything that relies on the electromagnet demagnetizing afterwards (IE: a doorbell) it wont work.

This is a requirement I have.  I need for it to not remain magnetized after I turn it off.

[webber]

"The secondary coil of a transformer must be winded with 0.8 mm magnet wire, but because nobody will read this let`s use barbed wire" 

Quite strange for me to hear about the inability to find simple iron. I`d use any suitable piece of scrap metal that responds to a little magnet.
If the situation is really SO bad, look for old transformer cores, or try to find some soft ferrite powder as nenjin suggested. Or ready ferrite cores in nearest electrical engineering store.
Also, I don`t think you should care about permanently magnetising the core.

[Siquo]

"The secondary coil of a transformer must be winded with 0.8 mm magnet wire, but because nobody will read this let`s use barbed wire" 

Quite strange for me to hear about the inability to find simple iron. I`d use any suitable piece of scrap metal that responds to a little magnet.
If the situation is really SO bad, look for old transformer cores, or try to find some soft ferrite powder as nenjin suggested. Or ready ferrite cores in nearest electrical engineering store.
Also, I don`t think you should care about permanently magnetising the core.

Well, if he wants to do a simple "pick up and release" magnetic grabber, if it's magnetised it won't release.
Opening up old (the heavy ones) wallwarts may indeed yield some iron cores.

[Bohandas]

Does anybody else find it ironic that the OP has run into the real world version of a common in-game problem?

[MarcAFK]

At first i figured this was in the wrong forum, so yes.
Edit: Wrought iron shouldn't be too hard to find, any manner of random bric-a-brac or random junk is usually made of it, random objects like candleholders, hooks etc, i know my house is cluttered with random junk but i'm sure even a normal place might have something made of iron that's unneeded and recycleable that might suit your needs...
Or look on ebay for excatly the thing you want to make, pull it apart and mke your own? :s
Edit 2: oh, ho, he has found Iron in the form of irony, very droll D:

[Levi]

Hmm!   I did manage to find this, which seems like what I want:  http://www.surplussales.com/Inductors/FerRods/FerRods.html

I'll see if they can ship by USPS to Canada. 

[MarcAFK]

Wouldn't ferrite magnetise though?
That page even says "residual flux, etc" which means it's already magnetic...

[Levi]

Wouldn't ferrite magnetise though?
That page even says "residual flux, etc" which means it's already magnetic...

For the (ICH) ROD7.5/50-3C80 one, it says its soft ferrite, which according to wikipedia it doesn't retain much magnetism, and can be reversed easily.  http://en.wikipedia.org/wiki/Ferrite_%28magnet%29


Unless I'm reading it wrong?

[webber]

Oh, not this again.  Guys, it is soft magnetic material, forget about permanent magnetisation! Also, even if it was usual steel, you would need something more serious then home-made winding to permanently magnetise it to noticeable level.