energizing magnets

is it possible to take a magnet or piece of metal and energize so that it attracts and then de-energize it so that it doesn't attract?

you mean like an electromagnet?

i'm not sure :dunno: i wanna energize a small piece of metal or magnet...i guess i may be refering to an electromagnet

i'm pretty sure if you rub a piece of metal against a magnet it will attract for a short while, then de-energize by itself

i wanna be able to do it at will....in a very small application

Electromagnet. You can make one out of household materials. Find a bolt, wrap it (neatly and close together) in a wire and pass a current through it. I remember doing this way back in 5th grade using big 'D' size batteries.
:)

think if i were to put a small one in a car it would mess up anything?

It would depend where you put it i guess.

Iron would probably be the best thing to wrap a wire around to use as an electromagnet.
Why do you want to put one in your car?

Use an iron ore rod, wrap some insulated copperwire around the iron ore tightly. You will be creating a solenoid, the more turns around the iron ore the stronger the magnet. Attach the ends of the copper wire (strip the about 2Cm of insulation of the ends) to a 12V battery.

Be careful, the solenoid will get pretty hot. The more turns the more current, the stronger the magnetic field, and the hotter it gets.

i smell some innovation here with the electromagnet. just a suggestion, if you want a magnet that will use little batery current, then just bust open an automotive relay like to the starter for example and modify it to fit your aplication. im all about trying new things on cars. you should see under the hood of my pontiac! its an ugly mess, but it is alot of never done before stuff. another suggestion, if you want the magnet to push away you could reverse the charge to the iron rod and put a small magnet on the object you will be moving with the electromagnet. electricity one way will push, the other way will pull. ive built alot of these before......

well i'm workin on a project with my car doors and want to be able to flip a switch and have the door stuck in place and flip it again and have the door come off...that's why i wanted to use an electromagnet....have the power hooked up to the car battery...but the applocatoin would be small and the magnet would only be like 1"x1" in size

You would need one huge magnet to hold a car door in place. In theory, you could do it, but its not a practicle thing to do.

Same concept for mag locks (security doors).

We flip a switch, you don't come in montherfucker!

well i'm not gonna hold the whole car door in...just where the latch is and flip a switch and push the door open

this is a cool mod. security

try something like a deadbolt action. have the electromagnet coil push out and pull in a magnet that is connected to a metal rod (or for a cool effect use several small rods) that would shoot out into pre ported holes on the edge of the inside of the door. am i on the same page as you?

if you used a switch that was simmilar to the ones that turn off your dome light when you shut the door, you could position it so that it would automatically lock the door in place simply by shutting the door. then you could open it from the inside with the switch

yeah that sounds cool but i'm runnin into a problem of what i'm gonna lock the door from the outside and seems like i'm gonna have to cut into the frame to do some of this stuff....i'm gonna have to look into this some more