SORTED Looking for small electromagnet

Other Hardware Sensors
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(OK, I know it's not a sensor, it's an actuator, so mods feel free to move this thread :D)

I'm thinking of using an electromagnet on the end of a robot arm to pick stuff up. So far the smallest one I found is here (14kg lift) but a tiny one that can lift a few 100g would do.

I know I can make one with an old nail and some wire, would rather buy one.

Anyone know of suppliers of small ones please?

TIA,

Jim

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Thanks dc.... I always forget ebay!

But as it happens, I remembered there was one in my junk box. It came out of a copier / printer that I stripped- I think it was part of the door latch or some other kind of interlock safety thing.

It has no label so I took a flyer and threw about 10VDC into it and it seems to work.

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For a small electromagnet consider making your own ?

Either way remember to drive it like a relay with a big enough transistor/FET and a free-wheeling diode.

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MarkT:
Either way remember to drive it like a relay with a big enough transistor/FET and a free-wheeling diode.

Yep... I might not control it from the Arduino at all, might just switch it manually straight from its power.

Bit of a hassle that these things seem to be 12v (it has no label though), but I tested it at 6v which is what the rest of the kit will use and it does work... I suppose it might not be as strong at low voltages but I want it to be able to lift a few washers or panel pins is all.

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JimboZA:

MarkT:
Either way remember to drive it like a relay with a big enough transistor/FET and a free-wheeling diode.

Yep... I might not control it from the Arduino at all, might just switch it manually straight from its power.

Bit of a hassle that these things seem to be 12v (it has no label though), but I tested it at 6v which is what the rest of the kit will use and it does work... I suppose it might not be as strong at low voltages but I want it to be able to lift a few washers or panel pins is all.

At half voltage it'll be about 1/2 the magnetic field and 1/4 the power dissipation - the power saving alone is probably
valuable.

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At half the magnetic field.it will provide one quarter or the lifting force. You can buy 6V solenoids via ebay if you need more lifting force.