This is an interesting trick to easily make a super strong electromagnet. If you take a 1 foot length of 4 and a half inch pipe and tack it horizontally off the edge of say.....a metal work table, you can wrap your ground cable neatly and tightly into a coil.  I had to tack a piece of flat iron to the front to keep the cable from falling off the edge.  The longer your ground is the better.  Wrap the entire cable as evenly as possible working it from left to right about 6 or 7 turns a row.  When you have 2 or 3 feet of cable left, clamp the end of it to the work table.  Adjust your amperage (current) to a hot temp.  Adjust your wire speed too if using a mig.  The smoother you get the arc the more stable the magnetic field will be.  Any pops or resistance causes the field to keep collapsing.  Get a hunk of scrap you can weld on.  Before striking an arc you need to know that this coil will make a super super strong EMF every time you strike or close the circuit by welding.  It may interfere with somebody's heart diffibulator or whatever those devices are called  It is strong enough to hold up a 30lbs sledge hammer  This electromagnet can magnetize your tools if you place the tool inside of the coil and weld for about 3 minutes.  When you take out the tool it will be a magnet.  Permeability of the material is a big factor on the strength of your magnet.  The more turns of cable and the amount of current flowing through the coil the stronger the magnetic flux density. Also, the poles will align according to which direction you place the tool inside of the coil.  Do not hold up a piece of metal up to it before striking because the force of pull is enough to smash your fingers off.  Hope y'all find this experiment intresting.  I'm still experimenting with mine.  Use thick wall pipe if possible .  

The welder would have to be set up for DC,  If AC it breaks the magnetic field in an object

 

This is true.  I forgot to include that it has to be a DC output welder.  I also forgot to add that you can also demagnetize anything you magnetize by putting it near another magnet.  Drill bits magnetize good enough to hang their own weight.  Straight metal objects like screw drivers seem to magnetize the best.

If the tool being magnetized is banged or tapped on while the field is on, it'll magnetize (or demagnetize) faster, stronger, and be more permanent. Of course this requires an assistant or an additional setup step for machinery to vibrate it.

Cool! It's perfect method for magnetize an uphostery hammer, Did you think it work with a common arc welder?

common arc welders are usually A/C  inverters {cheap ones} are D/C

mig welders are DC normally

Works great on my spud wrenches, and sleever bars, #ironworker#

A few wraps around welding rods will magnetize them enough to pick up filings.  They now have whiskers and will start welding when the whiskers touch the metal.  I was showed this trick back in the day when I was on a reweld crew at a power house.  We had to grind out and reweld defective welds.  Some were extremely hard to get to and even harder to scratch start the rod.  

DANG Donald, I sure wish someone would've shown me that trick!

Got it now though, thanks. Frosty