How to make an electromagnet?

ndemge

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It's raining, I'm tinkering...<br /><br />Need to move some cabinets, they weigh about 350lbs.... I have a forklift...<br /><br />Looking online on how to make electromagnet, I now understand the basic concepts, but not sure how much wire/amperage/voltage/resistance I'm working with...<br /><br />I have a 5/8" eyelet I'd like to turn into a magnet,<br /><br />How much Wire, what gauge, what voltage should the battery be, and do I need a resister inline?<br /><br />Any electro guru's in the house?
 

neumanns

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Re: How to make an electromagnet?

No electrical Guru, But.......How's about putting the fork's under the cabinet's :D <br /><br />Nah...Not near as much fun! :cool:
 

Xcusme

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Re: How to make an electromagnet?

HA! I have elecromagnetic door locks. They are used with controlled access panels. These magnets release when a keyfob or card reader is scanned and the door can be opened. These magnets can hold 1200 lbs. of force. Physically, they are about the size of a house brick, 12VDC and don't use that much current. Very fine coil wire is used and lots of windings.<br />One word of caution...beware of back EMF when you stop the coil voltage. The shock will wipe the smile off your face. :eek:
 

--GQ--

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Re: How to make an electromagnet?

Woooo.....to lift 350 pounds, the strength of the magnet is astronomical from a layman's stand point. The amperage requires is huge. Enough to cause serious injury and or death.
 

ndemge

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Re: How to make an electromagnet?

NO!<br /><br />...but after realizing this is not a simple evening project, that is how we will do it, muscle to move them onto the forks... <br /><br />But I now want to make one this winter :) sounds like a new project thread !<br /><br />
Originally posted by neumanns:<br /> No electrical Guru, But.......How's about putting the fork's under the cabinet's :D <br /><br />Nah...Not near as much fun! :cool:
 

waterinthefuel

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Re: How to make an electromagnet?

Xcuseme we have the same thing at the airport, used with secure access card scanners. You can't really break the bond easily, but you can if you are really mad! The door doesn't budge if your card fails to scan and you walk into it, it makes you look like an idiot!
 

rottenray6402

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Jul 27, 2004
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Re: How to make an electromagnet?

I don't need a door to make me look like an idiot, I can do that all by myself. The elecromagnet project sounds like a good way to curl your hair and cause damage to soft tissue organs.
 

bandit86

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Nov 17, 2005
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Re: How to make an electromagnet?

it all works down to ampere turns - the more of both, the higher the magnetic force created. the problem is after a while the wire itself is becoming resistive so a thicker gauge may be required. Like xcuseme said, disconnecting the powersupply to the coil will yield unexpected results. The coil acts sort of like a capacitor is to voltage. Coils keep constant current going, when the power is disconnected, it'll use the built up magnetic force to continue the current running through it by building an electrical potential difference- upping the voltage across the coil until the current can continue, causing a big spark.<br />this is where you have to be carefull, a 1amp circuit @12v is not much, enough to give you a jolt if you hold it wrong. If you are thinking about lifting 350#s, youre going to be near 20amp or so, when the current is broken you will probably see voltages as high as 100,000 volts. @20 amps, in that instant when the coil discharges, if it discharges through you, you will die. No doubt about it. <br /><br />I hope I didnt discourage you, but the forces exerted by a collapsing magnetic forses can be greater then you might expect. I would however carry on with this project as it sounds like fun. I would start by buying a couple hundred foot roll of 18ga wire, you will need a good solid metal core, something that fits through the center of the roll. I would not want to switch it through a handheld switch, I would definately runit through a relay so that when you flip a switch a relay drops out and youre isolated from the coil circuit. I dont quite think 12Vdc is enough either but a good place to start, for supply I would use a bridge rectifier on a 110V house supply, but try low voltage first. <br />at work I have seen 15000 turn coils at 110v and it's not quite impressive to look at but does get to be quite strong, most circuits have a collapsing circuit across the coil to keep the sparks down, nothing just a bigger resistor and a diode.
 
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