Electromagnets!

[Crazy Lou]

I have a feeling that this has been considered previously, but I'm not sure where... Anyway, I'm looking for some pointers on increasing the strength of a basic home-made electromagnet. I know greater cross-sectional area, more coils of the circut, and greater current will work, but any other suggestions or elaboration on the first three would be appreciated.

 

Goal of the project: create an electromagnet that will be able to hold securely to a sheet of steel despite sharp pulls of ~150N.

 

Maximum current available: whatever 1 car battery can offer. Also, sorry for the vague "question," but my plans for this are currently this vague...

[Klaynos]

lots and lots and lots of coils, you might also want to investigate different core materials for the magnets...you should be able to quite easily make something to resist 150N you might have to make the steel thicker at least around the clamping points next to the magnet....

[YT2095]

you can also focus the field to a single surface using a "cup".

imagine you have your soft iron core with it`s windings around it, and then place it into an iron cup so that one end of the iron core touches the middle bottom of the cup (probably a good idea to pour in resin afterwards too).

when you power up the magnet most all of the force will be on the one side

 

as for the above, lots and lots is Fine, but you`ll need a higher driving voltage to compensate.

the coils must be even and uniform also, you cant just wind them on any old way (it`s inefficient), side by side evenly is best.