Scrap electric motor?

woodhick · November 07, 2009, 03:36:58 PM

I have several OLD electric motors that are junk. Is it best to strip the copper out of them or just junk them complete?

Magicman · November 07, 2009, 03:50:59 PM

No question.....strip. You'll get little more than iron prices if left whole.

woodhick · November 07, 2009, 04:09:08 PM

Thats what I was thinking but how long does it take to strip the copper out of one? and what is the best way.

Magicman · November 07, 2009, 04:23:22 PM

First, disassemble it. Throw it all on the fire and burn it. That will remove the fabric ties and varnish. Next, just take a wood chisel and cut the ends of the coils off. The rest of the coils will then slip easily out of the other end.

Tom · November 07, 2009, 05:31:19 PM

Given only those two choices, stripping is the answer, but how about getting them rebuilt? If they are of any size, and your were using them before, you might be able to use them again. Unless you wind your own, 1 horse motors are a dime a dozen, but when you get into the 5 horse and above, rewinding becomes a bit more feasible.

Do you have a local rewinder? It's becoming a lost art.

gary · November 07, 2009, 06:47:51 PM

I make my living selling scrap. If they are small motors (under 1 horsepower) you will be better off selling them the way they are. Magicmans way will work. It will take you about 3 hours for each motor. If you have a sawzall and a torch you might clean them in an hour each. You will only get 4 or 5 pounds of copper from each one. Number 1 copper was $2.05 a pound this week. I just sold 1,000 pounds of them uncleaned this week for $0.20 a pound. It takes me about 2 months to save up that many. It took me about 2 hours to load them and haul them in. I have 3 motors from 3 to 10 horsepower to clean next week. It will take me a day to clean all 3. I should get around 100 pounds of copper from all three. I will also get over a ton of steel from all 3. Hope that helps you.

Fla._Deadheader · November 07, 2009, 06:48:49 PM

Guys into Renewable Energy are rebuilding them using NeoDymium magnets on the rotor.

Might ask around on the RE forums, before trashing them ???

Magicman · November 07, 2009, 10:12:33 PM

Quote from: gary on November 07, 2009, 06:47:51 PM
Magicmans way will work. It will take you about 3 hours for each motor.

I don't work that slow. I worked for Electric Motor Service too many years and rewound too many motors. They would have run me off..... :D

caver · November 08, 2009, 10:15:11 PM

We had cutting disc mounted on a long shaft. Burn the motor out in the oven and then run that cutting wheel around the end windings.
As far as rewinding,,,,,,motor shops can sell you a new motor cheaper than a rewind up to 40 hp. I think that was the number when I worked at a rewind shop. I'm sure it is much higher now.

Tom · November 08, 2009, 10:57:30 PM

Motor rewind shops that have the office help, retail motors, pay salesmen, have 5 or 6 rewinders working in a 2000 square foot shop are quick to tell you that what you have is junk and you need to buy a new one.

Rewinders, like my 90 year-0ld friend, Mr. Shippey, who rewinds in a 100 square foot corner of his woodworking shop will even work on 1/2 horse and 1 horse motors, if he likes you. Most of the motors in the dairies and chicken houses are 3/4 or 1 horse. He will make a trip to the farm and pick them up himself if he isn't busy. That is if you have a bunch of them, and the farmers usually do.

He winds a lot of 5 horse and larger.

The thing is that motors that don't run, don't always need rewinding. I've seen him put one on the test bench and look at voltages, start and stop, listen to the bearings, check switches, etc. and saying, "That's just a burnt switch, that should make him happy."

Then when you come pick it up, you will have to keep him from carrying it to your truck for you, while y'all talk about the deer so'n so shot, or the economy of the Nation, or discuss his ideas of the congress or senate decisions, or have him tell you about his trucks latest dilemma.   You might get asked to sit in the yard swing and have a Coca Cola with him, or wander to the back and talk to him as he checks a bee hive.

It makes you afraid to ask, "how much?"

"How's $10 sound?", he'll say. That probably entailed a half hour of his time, the installation of some used parts and his cleaning it and touching up the paint.

If he rewinds a motor, he tells me, "I don't know what to charge sometimes, but I figure a totally rewound and rebuilt motor should be worth 2/3's of the price of a new one."

He's a dying breed and can do just about anything.

There's lots of business like that done around here. You don't get too uppity about yourself because everybody has a specialty of one kind or another. Next week, you might be at his house and he'll hand you a free quart of honey. Or, you might be at a chicken farmers and he'll hand you a five pound bag of cleaned and dressed quail. Or, your truck might stop out on the road and one of them that makes his living by working on big timber trucks might stop and say, "can I help?"