Proper way to magnitize with DC machine

[Bob]

I would like to magnatize some steel auto drain plugs. What would be the best way to do that with an HH-135? ... without damaging the machine, torch, and not launching the steel plug.

Bob

[dee]

Originally posted by Bob
I would like to magnatize some steel auto drain plugs. What would be the best way to do that with an HH-135? ... without damaging the machine, torch, and not launching the steel plug.

Bob

Bob,
I can tell you how you can use a coil from an old washing machine fill-valve solenoid on 110 line voltage to magnetize, but I'm afraid I dont know how much wire would dissipate the wattage you'd likely be dumping in to anything with your welder may hook up to.

Note that the way you have the part oriented will have slight effect on how well the part will take the magnetization, and that I have magnetized steel bars by merely striking them with a hammer.

The commercial magnetic plugs I see have a bona-fide magnet affixed into them; why not get an appropriate magnet (Grainger, McMasterCarr etc) and drill a counterbore for it to fit into on the end of the plug. They're made from an alloy selected for it's magnetic properties and will be stronger and hold its power longer than that magnetized screw.

Are you planning to magnitize these plugs for sale or for your friends? They only cost a couple bucks at parts stores.

Have you seen the type of magnetic filter they use in automatic transmissions?

[customwelds]

I hope I'm not pirating your thread, but this seems the most appropriate place to ask. Dee, would you care to explain how you magnetize a bar of steel merely by stricking it with a hammer? I was reading your response and that just stuck out and intrueged me. Any other info on that subject would be really cool to learn as well. Thanks!

Bob, I agree with Dee unless you need to do it your way. It seems like it would be a better idea to buy one that is properly spec'd for your application for a few bucks. Just my humble opinion though! Good luck either direction you travel.

[dee]

Originally posted by customwelds
Dee, would you care to explain how you magnetize a bar of steel merely by stricking it with a hammer?

The usual cost is a beer.

What I'm doing is imposing a shock to jostle the random oriented but naturally magnetic molecules within the steel into alignment. What is necessary is a magnetic field (I use the Earth's) a straight steel bar, and a means of imposing the vibratory shock... a hammer and some kind of anvil. (as a kid I used a sidewalk and chipped it, sending pieces flying into the face of onlookers- it was OK; they were ugly anyway)

Test the steel bar carefully for magnetism. Place it on a hard, firmly suported surface, aligned along the magnetic N/S azmuth, and strike it with a very sharp blow with a (hardened) heavy hammer- a ("dead-blow" won't do it...). A single blow may suffice, sometimes more than one is necessary. I don't recall if it was best to hit one end or the center. It should become sufficiently magnetic to pick up some steel filings. Be sure it's not the filings that are magnetic.

[customwelds]

Hmm, that's really interesting. Thanks for filling me in. I may try it sometime just for fun. I'm still a kid (Ripe old age of 16!) so I'll use my driveway and aim for the obese girl who resides across the street from me. Haha, just playing. I'll let you know what I find out if I can go play with some metal tomorrow.

[dee]

Originally posted by customwelds
... I'll use my driveway....

Understand the driveway isn't really HARD enough to do it right, particularly if it's blacktop.
If you have any Karate friends they know how hard it is to break a board if the board holder does not hold the board firmly. Remember the goal is to get the energy focused into the bar and not through the bar into the supporting surface. Still&all, it may work, but don't judge the experiment based on your findings until it's done "right".

[slowrev]

I was always taught that sudden shocks to magnets would demagnetize them.

[customwelds]

I understand. Mine is made almost identical to the sidewalks in my hometown in Texas. We don't have sidewalks here at this neighborhood in okie land but if I don't get any magnetizing action going on, I may take it to Vo-tech and see what happens if I use one of our big @$$ anvils

[dee]

Originally posted by slowrev
I was always taught that sudden shocks to magnets would demagnetize them.

It's probably a bit too extreme a word- it suggests some terminal finality- to say "demagnetize"; it's a matter of degree (or actually Gauss)

It's not untrue though; the same mechinism which is magnetizing our steel bars is acting on the more coherently aligned molecules in your strong magnet to permit them to "relax" a bit and weaken it... apparently that degree of alignment isn't natural. Magnets are known to lose their strength over time- wacking them tends to speed things up, particularly when they're not aligned properly to Earth's magnetic north.

Very much depends on the alloy from which the magnet has been made

[BillC]

Another way to magnetize a steel by cold forming is drawing it as in tubing or wire. This can cause confusion when trying to identify grades of stainless steel. It is common to try to identify 300 series stainless as non-magnetic, but that is only true if it is annealed. Cold-drawn stainless tubing and stainless steel aircraft cable are mildly magnetic.

[dee]

[i]...It is common to try to identify 300 series stainless as non-magnetic, but that is only true if it is annealed. Cold-drawn stainless tubing and stainless steel aircraft cable are mildly magnetic. [/B]

hmmmmmmmmmmmmmmmmmmmm...

...the more I think about your signature motto the more I like it.