Discharging high amounts of amperage in a very short time.

Previously I asked this question, except I wanted to build an electromagnetic dent puller. But no one gave me specific ideas or instruction of how it could be done, instead everyone told me different ways to pull the dent out, or how the metal looks.. Anyway.

I have a lot of copper wire. And I have a bunch of magnets and ferrous cores, iron rods.. etc. I am wondering if I can create a very powerful burst of magnetic energy with a few winding's of copper around a ferrous core. I'm talking enough to push two very heavy objects apart, such as a television or couch...

1) Copper will be wound around about 40-60 times
2) High amperage discharge from capacitor bank
3) Possible explosion or melting wire?

Thank you... again

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CrLz4 years ago
MRI's have fast switching electro-magnets, which can cause mechanical vibrations. In the very old research scanner I first learned on, we could make the gradient coils slap the patient barrel with certain sequences. Sounded like a hammer hitting the barrel about 100 times a minute as the coils were pulled back and forth.

So, what you are thinking about it somewhat possible. I doubt you'll get much distance, however.  The magnetic field drops off very quickly, so two repelling coils will not have much time to act.  Probably could get an initial jump.

To discharge a lot of amperage, fast, i guess the old way was using banks of capacitors, all discharging at same time.  I think MOSFETs are more contemporary way of stacking up charge in tight pulses.  If you discharge a car battery too fast, watch out for boiling the battery acid and causing a steam-explosion and/or gaseous acid.

Maybe kelseymh will chime in, he is the real expert in these matters.
Justdoofus (author)  CrLz4 years ago
Wow, I didn't know MRI's did that. I heard they are awfully loud, and maybe this is why. Thanks for the comment, MOSFETs sound like a good way
Goodhart4 years ago
First, the "poles" would need to be opposite, in order to push. If too high in voltage/amperage, the wire will vaporize, depending on size. It COULD get very hot
Justdoofus (author)  Goodhart4 years ago
Thanks for the comment, yeah. I have two electromagnets that I wound with old 18-20 gauge industrial motor copper, and wound it around an iron core.. I put one camera capacitor worth of voltage through and it jumped slightly..

So I am assuming that I could push hundreds of amps through a copper winding in one shot without vaporizing it, I wouldn't say thousands.. The reason I am asking is because no car battery or voltage source can push amperage out fast enough to cause an 'explosion of magnetic energy' without either burning the coil out, or the voltage regulator..
Your last statement kind of says it all....if you pushed it out fast enough, with much more power behind it, you'd pretty much cause something to crash and burn. If it's not too expensive to do so, you could make a sort of test core to try it, but protect yourself in case of melting/flying metal.
BTW: I missed an opportunity of a life time about 20 years ago at work. They were moving from a mainframe computer that filled a room to the then new AS/400 midframe. The Voltage conditioner unit they used had a coil in it with solid copper wire wound around the core that was bigger then 0 AWG. I just didn't know how I would have gotten the beast of a coil out of there :-) (or where I could have put it).
Justdoofus (author)  Goodhart4 years ago
Oh wow, are you serious? Bigger than 0 AWG, I don't think I've ever heard of copper wire that big before, I don't even know where I'd get it...

Anyway, yeah, I figured it would vaporize, but my first experiment was to place two coils wound around their own individual core, placed on a cylinder in an engine, and then when they meet up with each other at less than a millimeter, it would fire with high current to repel each other.. That didn't work.. Didn't EVEN try to move the piston. LOL.. Anyway, thanks for your replies.. And jeez, 20 years ago, I wasn't even born until 95.. So around 91-92 is when you saw this coil.
Toga_Dan4 years ago
In case anyone aint familiar w/the phenomenon:
http://www.youtube.com/watch?v=gzcq755ktew&feature=relmfu

Usually (perhaps always?) This is done with aluminum cans. I dunno if it'd work w/ steel.

I'm not sure if I completely "get" what's happennin, but assume that current is induced into the can, producing a N at the same end as the N of the coil. N repels N. Is that accurate?

I gotta ask, justdoofus, are you versed in electrical safety? Also, do you have safety glasses, hearing protection and a fire extinguisher around for this?
CrLz4 years ago
Yep, that's why MRI's are loud.
American cable sixes go WAY beyond 0AWG into the "Aughts", 0000 pronounced 4 aught is about 1/2" across.

You can put many thousands of amps through that before it will fuse in a half-mains cycle - 0000 fuses at 173,000 Amps, applied for 32mSec.