How can I cool down an electromagnet?

Hi instructables...I have made a small electromagnet for a project of mine....actually I made it to make an electromagnetic or relay switch...I intend to use it in a robot...I have this awful keeps getting hot..I would really appreciate if you told me a way to cool it down...and increasing the number of turns of coil or using less voltage or current is not an there any other way...I used a cooling fan but it didn't is there any other way?

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tylervitale5 years ago
If you don't care whether or not you made the magnet, I find pencil sharpener motors like this one in the image attached to be really effective. They don't heat up too bad, and I rigged one up with a 30 VDC supply and it was able to lift 5 pounds several feet into the air with ease.
I remember reading that the key to an efficient electromagnet is in the winding. I saw an electromagnet in a science demo magazine capable of lifting up to 25 pounds on only 3 volts. The reason it could do this is because it was precision wound so that the coils match up perfectly with the magnetic field.
If your windings are messy, clean them up. I used to think it doesn't matter myself but it really does.
Dang it. I don't think the image uploaded for some reason. Just google pencil sharpener motors.
Well, a really off the wall theory, but here we go:

Try to find some really small copper tubing. I think 'capillary copper tubing' is what you want. Wrap this tubing around the core (being careful not to kink it), then hook up a liquid-cooling system to the coil.

The copper will now serve a dual purpose, cooling as well as generating a magnetic field.

Once again, this is a theory, and I have no idea if it will work. But it's probably worth a try, if you can find copper tubing small enough.
gopal05 years ago
you can use an bigger nail then rap it with the coils then rap it tight with alimuniom foil then attach 2 or more big peaces of thick copper then add more negitive terminals in those thick copper wires and it you make the thick copper longer than the nail then it would act as magnetic sebelizer if you make them paralel
Have you used a ferromagnetic core ?
Wisaam (author)  steveastrouk5 years ago
I have used a simple iron nail as the core.
You're saturating the core. Make it bigger, by wrapping more nails.
Re-design5 years ago
How hot does it get? Lots of electrical devices heat up somewhat in use, it's just a result of their work. If you don't let out the magic smoke then it didn't get too hot.
Wisaam (author)  Re-design5 years ago
I don't know the exact temperature but it gets hot enough that I can smell the smell of melting insulation of the copper wire used in it for winding..
blkhawk5 years ago
Try using a heatsink. Also some sort of thermoelectric cooling device.
rickharris5 years ago

Push less current through it

ext ream possibility water cooling
Wisaam (author)  rickharris5 years ago
As I mentioned in the question...I cant push less current through it...I tried it but it greatly reduces the strength of the magnetic field...but thanks anyway for the suggestion..I'll find what I can more about liquid cooling..