Electric motors

Hi have a question about electric motors the strings on the motors in sealed units come off easily with one snip then I can pull it off. The strings on other motors not in oil and exposed to the elements and age they have a resin that makes them not fun to get off. I would like to know how other people get the strings off? I was thinking of using a torch but not sure on that one. I have a ocilator and a sawzall. Thanks. I have 124lbs of fractional motors to do 72lbs of small fan motors and not sure on the 9lb motors maybe 30 or more of those. I only get .15 for electric motors so im looking to get copper price and I have to remove the strings.

Hey Mike,

I hope you and everyone had a good holiday. I've been doing generator stators & rotors lately. They're all dipped in a bucket of varnish and then baked in an oven when they're first made. The idea is to keep all the windings in place when the machine is running. Basically the same idea with electric motors that are varnished. It helps protect the windings.

Got 11 lbs of copper out of an 8 KW home standby generator a couple of days ago. Had one that was 24 lbs once. Most portables are about 7 lbs .... though i'm seeing more & more wound with aluminum these days.

You don't have to worry about the string if it's going as #2 copper. A fussy scale guy might complain about the insulated wires that are held in place by the string. It's easy enough break varnished string by pounding the motor winding with a hammer.

Look at the way that the winding is bent over on the end of the motor. Hit it sideways and bend it up straight. The windings pull out easier if they've been pounded on and loosened up some.

This is a pretty good video on how electric motors are wound. Go about 5:25 minutes in and you see how they bent the windings over with a hammer. Bending the windings back up a bit makes them more manageable and easier to strip out if they were varnished into place.

https://www.youtube.com/watch?v=XRYSFalqe2U

Quote:

---

Originally Posted by hills

Hey Mike,

I hope you and everyone had a good holiday. I've been doing generator stators & rotors lately. They're all dipped in a bucket of varnish and then baked in an oven when they're first made. The idea is to keep all the windings in place when the machine is running. Basically the same idea with electric motors that are varnished. It helps protect the windings.

Got 11 lbs of copper out of an 8 KW home standby generator a couple of days ago. Had one that was 24 lbs once. Most portables are about 7 lbs .... though i'm seeing more & more wound with aluminum these days.

You don't have to worry about the string if it's going as #2 copper. A fussy scale guy might complain about the insulated wires that are held in place by the string. It's easy enough break varnished string by pounding the motor winding with a hammer.

Look at the way that the winding is bent over on the end of the motor. Hit it sideways and bend it up straight. The windings pull out easier if they've been pounded on and loosened up some.

---

Yes good Christmas had ham.generator has a dc motor yea? Those have a higher copper content I read I think then fractionals then regular ac motors dc motors suck. I have two that are 1/10th HP and are wound like a ceiling fan motor but are from a furnace motor so that's different.

All of the motors on the furnace gun ... that i've seen so far ... are aluminum wound. The blower motors on a hot air furnace are quite often aluminum. The DC motors are pretty difficult because of the way the copper is wound on the rotor. Was watching a Russian scrapper on youtube. He threw his rotors in the wood stove once it was nice and hot. He heated em' up and then dropped them into a bucket of water. They were much more cooperative after getting " The Treatment " !

I was banging away on those strings that hold the copper windings together this evening. The hammer worked well enough but then it dawned on me to use the hatchet. The hatchet worked even better. It cut those strings and broke up the varnish like nobody's business.

Quote:

---

Originally Posted by hills

All of the motors on the furnace gun ... that i've seen so far ... are aluminum wound. The blower motors on a hot air furnace are quite often aluminum. The DC motors are pretty difficult because of the way the copper is wound on the rotor. Was watching a Russian scrapper on youtube. He threw his rotors in the wood stove once it was nice and hot. He heated em' up and then dropped them into a bucket of water. They were much more cooperative after getting " The Treatment " !

I was banging away on those strings that hold the copper windings together this evening. The hammer worked well enough but then it dawned on me to use the hatchet. The hatchet worked even better. It cut those strings and broke up the varnish like nobody's business.

---

Hm I have a hatchet thing someone. Made out of a tire iron lol. I sharpened it sort of lol. I mite try that. Or heat them up haha I will keep you posted on the results.

Quote:

---

Originally Posted by mike1

Hm I have a hatchet thing someone. Made out of a tire iron lol. I sharpened it sort of lol. I mite try that. Or heat them up haha I will keep you posted on the results.

---

I'm going the slow route used ocilator to cut strings pull string off take plastic inserts out the ones you can pound down I mean then just pull the copper out unless it doesn't cooperate couple or them didn't I got 8 done so far of the fractional ones I got 12lbs of copper so far. Doing more tomorrow.got a torch in case I need to use it tho. And a bucket of water lol.

Quote:

---

Originally Posted by mike1

I'm going the slow route used ocilator to cut strings pull string off take plastic inserts out the ones you can pound down I mean then just pull the copper out unless it doesn't cooperate couple or them didn't I got 8 done so far of the fractional ones I got 12lbs of copper so far. Doing more tomorrow.got a torch in case I need to use it tho. And a bucket of water lol.

---

It's been a few weeks Mike. How are things going ?

Whew ... it seems like there's been an ungodly amount of work to be done on this end lately. I'll be glad when things finally settle down for the winter. The Christmas holidays make for enormous amounts of material entering the waste stream. Not many air conditioners this time of year though ..... ;)

Quote:

---

Originally Posted by hills

It's been a few weeks Mike. How are things going ?

Whew ... it seems like there's been an ungodly amount of work to be done on this end lately. I'll be glad when things finally settle down for the winter. The Christmas holidays make for enormous amounts of material entering the waste stream. Not many air conditioners this time of year though ..... ;)

---

Been pretty busy got all my rads done from the last of the acs 37 of them I have 37 compressors to cut open to get 74lbs of copper out of them the strings on those just pull off haha. The yard I go to says I have to take all the strings off or they will give me electric motor price if I wanted that I would have left the motor whole haha. My blade should go through the compressors providing I don't snap it off at the base haha. Looking to try a cold chisel for the motors to get one end off not sure if it will work or not going to try it on one motor and see first have to get a cold chisel. The hand made tool didn't work so well for the wires it does however work for the rivets on the 9 lb motors I have 84 of them down to just the copper middle part each one is 5lb then 2lb of copper out of them when I'm done I should have close to 300lbs of num 2 copper. I'm getting there slowly but surely.

It's been pretty busy with the day job lately. Busy with things to do on the homefront as well. It hasn't left much time / energy for scrapping.

It's a hard call on the sealed units and fractional motors. The copper is there .... but it's quite a bit of work for a modest amount of gain. I did a household refrigerator compressor last month. The yield was about 1.4 lbs of #2 copper. It's something to do if you have the time i guess. Better than nothing at all in the dead of winter. Keeps your hands busy doing something useful. Nothing wrong with that.

Those Diablo carbide sawzall blades sure are good. I used an 8 tooth per inch (TPI) for cutting open that sealed unit. It wasn't at all hard to do with that compressor firmly screwed down to the bench. All the oil stays down at the bottom as long as you keep the whole thing upright while you're working on it. You just lift out the motor and set that aside for processing later. Unbolt what remains of the compressor and just pour the oil out into a bucket. Not such a messy job as you would think if you work out a method.

Did a bunch of rads awhile back. It's funny because you would think that a sawzall blade for cutting off the ends is just a sawzall blade. I tried the Diablo 22-24 tpi carbide strip and it made a pretty big difference. It made such a clean cut that the little copper noodles were so easy to remove from the steel ends. You don't get much copper from all the noodles and AC lines but it eventually adds up to a few pounds after awhile. There seems to be more value in the clean rads themselves. The noodles are just the gravy. You could sell the ends as CBM and you wouldn't be out much. It would save the time fussing with them for little bits of copper.

Anyhow ... just my experience so far. :)

Quote:

---

Originally Posted by hills

It's been pretty busy with the day job lately. Busy with things to do on the homefront as well. It hasn't left much time / energy for scrapping.

It's a hard call on the sealed units and fractional motors. The copper is there .... but it's quite a bit of work for a modest amount of gain. I did a household refrigerator compressor last month. The yield was about 1.4 lbs of #2 copper. It's something to do if you have the time i guess. Better than nothing at all in the dead of winter. Keeps your hands busy doing something useful. Nothing wrong with that.

Those Diablo carbide sawzall blades sure are good. I used an 8 tooth per inch (TPI) for cutting open that sealed unit. It wasn't at all hard to do with that compressor firmly screwed down to the bench. All the oil stays down at the bottom as long as you keep the whole thing upright while you're working on it. You just lift out the motor and set that aside for processing later. Unbolt what remains of the compressor and just pour the oil out into a bucket. Not such a messy job as you would think if you work out a method.

Did a bunch of rads awhile back. It's funny because you would think that a sawzall blade for cutting off the ends is just a sawzall blade. I tried the Diablo 22-24 tpi carbide strip and it made a pretty big difference. It made such a clean cut that the little copper noodles were so easy to remove from the steel ends. You don't get much copper from all the noodles and AC lines but it eventually adds up to a few pounds after awhile. There seems to be more value in the clean rads themselves. The noodles are just the gravy. You could sell the ends as CBM and you wouldn't be out much. It would save the time fussing with them for little bits of copper.

Anyhow ... just my experience so far. :)

---

Nice I'm thinking about getting a SDS hammer drill with a wide chisel bit to chop the motors in half then just pull the copper out of both ends. Ideas on the brand and wide chisel bit to use? I don't think they make a wise chisel bit for metal just concrete and tile. Can I still use it?. For cutting through the steel ?. Good for you never tried those blades with that teeth count anyway.

I've got a Bosh Bulldog SDS Extreme. I've had it for years and it's never given me a bit of trouble. It's a good tool.

Don't know about splitting motors apart though. I think you would need something like a chisel bit that was a foot wide. The point of it would have to be pretty sharp to wedge between the laminates and split the motor. It doesn't seem like the tool would have the power to do that. I think you would need something like a 40 ton hydraulic press to split a motor apart.

I usually cut one end off the windings with an angle grinder and then use a punch to drive out the copper. It's the best way i've found to do the job.

Quote:

---

Originally Posted by hills

I've got a Bosh Bulldog SDS Extreme. I've had it for years and it's never given me a bit of trouble. It's a good tool.

Don't know about splitting motors apart though. I think you would need something like a chisel bit that was a foot wide. The point of it would have to be pretty sharp to wedge between the laminates and split the motor. It doesn't seem like the tool would have the power to do that. I think you would need something like a 40 ton hydraulic press to split a motor apart.

I usually cut one end off the windings with an angle grinder and then use a punch to drive out the copper. It's the best way i've found to do the job.

---

I saw a video on it not sure if it's a hammer drill or not it says it is though is it or is it something else ? They sell it for 200$ for the machine and 5 bits and 150$ for shipping and 5 percent fees the bit they use is 5in wide almost. I paid 199 for a Milwaukee corded and free angle grinder plus 30$ for a chisel bit that's for concrete cant find any chisel bits made for chopping through metal haha.https://youtu.be/cUXaUBScqDQ?si=NC7Y3BoF_xSzgGPi

I did 18 motors in 2hrs with the ads hammer drill works pretty well hardly any dust still have a long way to go haha. I'm going to get a wider bit though I still have the string to take off though that part sucks.

Quote:

---

Originally Posted by mike1

I did 18 motors in 2hrs with the ads hammer drill works pretty well hardly any dust still have a long way to go haha. I'm going to get a wider bit though I still have the string to take off though that part sucks.

---

I looked into the SDS bits Mike. The widest one i was able to find was 6" wide. They aren't common but they are out there.

Try google search term 6" wide SDS chisel bit. It will turn up a few results.

Amazon has them I think. Going to do more today

See how it goes. I've got a 3" wide chisel bit with a slight bend that i bought a few years ago for a wintertime dig up job through frozen ground.

As i remember .... it wasn't a sharp chisel when it was bought new. Their main use seems to be to chisel ceramic tiles off a floor or wall.

You might need to grind it to a sharp edge if you are looking to split motors in half. The wider the bit .... the more the hammering force of the tool is spread out over a larger area. The narrower the chisel .... the more the hammering force of the tool is concentrated in a small area to do the splitting job.

There might be some trial and error to find the tool that does the job best.

Quote:

---

Originally Posted by hills

See how it goes. I've got a 3" wide chisel bit with a slight bend that i bought a few years ago for a wintertime dig up job through frozen ground.

As i remember .... it wasn't a sharp chisel when it was bought new. Their main use seems to be to chisel ceramic tiles off a floor or wall.

You might need to grind it to a sharp edge if you are looking to split motors in half. The wider the bit .... the more the hammering force of the tool is spread out over a larger area. The narrower the chisel .... the more the hammering force of the tool is concentrated in a small area to do the splitting job.

There might be some trial and error to find the tool that does the job best.

---

Wow didn't know that about the hammer action thanks. I have 13 big ones left and ten big ones I have to get the fans and outee steel off of them I can do those then it's onto the 37 ac compressors for the copper motor and a few lbs of brass if I'm lucky haha. Plus I have a 5 gal bucket full of relays from the acs so brass on those to. Then the small motors that's going to be fun. So I have split 71 motors so far I sharpend the chisel twice so far. Also tried to make it a bit thinner less resistance I figure kinda hard to get it between the plates sometimes haha. Beats having to buy blades then I get to take all the strings off yay.