I bought a "Liebert Datawave server room power conditioner" for $50 from the military.
Since no one wanted to buy it above scrap value, we decided to scrap it. We sawed off the windings from numerous transformers. The "conditioner" has about 250 lbs of heavy copper windings (rectangular in cross section), plus about 36 Dielektrol oil filled 660 VAC capacitors.
My question is about the 250 lbs of copper windings with rectangular cross section. They are baked together with some waxy paper and lacquer.
What is the easiest way to get rid of that stuff, other than burning. I am familiar with burning, but I want to know other alternatives. Ideally, I would like to turn it into #1 copper scrap, not #2 like the burned stuff.
If it's truly laquer, then laquer thinner should cut it..
Suggest test to make sure and if so, shear it away from the core and into manageable sized pieces using a knife press, skil saw or something like that and then soak the pieces in a metal bucket full of the thinner.
But thinking it could be shellac, in which case you would want to use de-natured alcohol instead...
Most likely not shellac. From Wikipedia: "Insulation
Modern magnet wire typically uses one to four layers (in the case of quad-film type wire) of polymer film insulation, often of two different compositions, to provide a tough, continuous insulating layer. Magnet wire insulating films use (in order of increasing temperature range) polyvinyl formal (Formvar), polyurethane, polyamide, polyester, polyester-polyimide, polyamide-polyimide (or amide-imide), and polyimide. Polyimide insulated magnet wire is capable of operation at up to 250=B0C. The insulation of thicker square or rectangular magnet wire is often augmented by wrapping it with a high-temperature polyimide or fiberglass tape, and completed windings are often vacuum impregnated with an insulating varnish to improve insulation strength and long-term reliability of the winding.
Other types of insulation such as fiberglass yarn with varnish, aramid paper, kraft paper, mica, and polyester film are also widely used across the world for various applications like transformers and reactors. In the audio sector, a wire of silver construction, and various other insulators, such as cotton (sometimes permeated with some kind of coagulating agent/thickener, such as beeswax) and polytetrafluoroethylene (Teflon) can be found. Older insulation materials included cotton, paper, or silk, but these are only useful for low-temperature applications (up to 105=B0C).
For ease of manufacturing, most new magnet wire has insulation that acts as a flux when burnt during soldering. [1] This means that the electrical connections at the ends can be made without stripping off the insulation first. Older magnet wire is normally not like this, and requires sandpapering or scraping to remove the insulation before soldering." Karl
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Ultimately, it would have been worth a lot more as a ferro-resonant transformer (to someone) than even as #1 scrap. (sigh)...
It's not lacquer, it's Hysol Varnish. The thing was probably vacuum varnished, as were most transformers, before they started sending all that business to China.
Ethylene (or methylene) Chloride will dissolve it, but not _completely_. It will leave a gel-like gunk that will have to be washed away with a heavy stream of water, or removed by tumbling/washing -- much like a tumble de-burring operation, but with a water rinse.
Methylene chloride is the solvent in common solvent-based paint and varnish strippers. Only... it would take a LOT for 250lb. Unless you dedicated a whole barrel of the stuff to this purpose, that would be an expensive one-off experiment.
Another thing that will soften varnish so it may be washed off is hot lye solution. That's cheap, but it's dangerous, and has to be near boiling to work well.
Question, Ig... what's #1 brass scrap selling for these days? Is there any advantage if it's all one alloy, and very clean?
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Karl, that really gave me a snicker! Apparently, that was written prior to 1965.
Belden Wire came out with "Beldsol Insulation" around then. It's advantage was that you could just dip the ends of the wire in a solder pot, and they'd tin. Contrary to the report above, we were making small chokes and transformers with Beldsol wire in the 1960s.
I think that what you are getting at is right, nothing else works as well as burning. (note that varnish is not as bad to burn as would be wire insulation).
Lloyd, there is not one price, you need to call your local scrap yards. Quantity and consistency are always an advantage. Also, open a corporate account. They treat you better.
I am scrapping a fair amount of stuff now, taking dump trucks of ferrous and scrapping copper by the half ton.
Here's a picture of my above mentioned dump truck.
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I work hard to learn scrapping business (meaning, buying stuff for the purpose of scrapping). So, I am still a beginner in the scrapping business.
The last fun project was buying a 80 "ton", room sized, 6,500 lbs "Trane water chiller". It yielded 500 lbs of clean copper, 666 lbs of copper aluminum radiators, 5,000 lbs of iron and a bit of wire, plus
Excellent advice. I just saved a couple bucks this morning by having a Ewing Irrigation cash card. I picked up a box of 500 landscape staples, for when I take out my front lawn. It's going to be nice without the leaves/branches dropping every year, roots ruining mower blades, moss on the roof, etc.
I guess it's running fine? How are you doing with the semi tractor?
You're definitely in the right area for that, Ig.
Whassa "copper aluminum radiator"? Price? Is iron still going for $140T? How much is clean copper vs #2?
-- Shake off all the fears of servile prejudices, under which weak minds are servilely crouched. Fix reason firmly in her seat, and call on her tribunal for every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason than that of blindfolded fear. -- Thomas Jefferson
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Not likely with windings of that vintage. It would be a natural organic (i.e. vegetable) varnish (as opposed to a synthetic urethane) like Hysol brand, which was specifically formulated for vacuum potting of transformers.
I did a stint as the senior lab tech for Florida Transitron, WAY back in the day. A few transformers were potted in more exotic compositions (like epoxies), but most were simply put in the big Hysol vacuum pot, then drained and rolled into the oven for a 24-hour bake-out.
Well ... there used to be a chemical available in small bottles with a brush for dissolving the insulating enamel on the wire. If you dissolve that, the paper will go away too. But it was nasty stuff, and I would want a fume hood to use it in if I were working on something as big as your 250 lbs of copper. IIRC, it was called "Formex" IIRC and sold by General Cement (who sold a lot of electronics chemicals back when). I usually scraped the enamel off the end of magnet wire, but when working with the tiny stuff (e.g. #50 and smaller), one scrape and you cut though the wire, so this was the only way to do it reasonably.
I think that it was related to the stuff which an employer back in 1960 used to dissolve epoxy potting compound (and it also dissolved the epoxy from G10 circuit boards, and the Bakelite shells of resistors (along with the color code bands. :-) That that certainly *was* used in a fume hood.
Not sure that you can get any of that stuff these days. :-)
It was typically called an "enamel" not a lacquer or shellac. Specially formulated to be tough enough to avoid cracking and splitting off when the wire was bent in the process of winding the coils. I think that "Formvar" was a name of what was used, and what was likely used in this.
Tetrahydrofuran? THF.. Used nowadays in PVC solvent-welding-"glues".
One reference states that 67% methylene chloride, 17% phenol, 4% ammonia works for most magnet wires.. The rest is thickeners etc. for making it stick to magnet wire. Used to be "strip-X" as a commercial product. I have not tried this myself.
Is it really more economical to use some hazardous chemical (producing chem waste) to "purify" the copper scrap, compared to just selling the copper as is (with the paper etc.)..
Your local chemical supplier is happy to sell you anything.. If you are a company, of course.
The problem here is that it wouldn't. This is not a standalone, spec'd and rated ferroresonant transformer with it's own housing, it's a custom unit with no specifications and ratings, unenclosed (on it's own) that was an OEM part in an obsolete product. Scarp value really is it.
The dump is running fine. The semi, is also running, but we are not yet using it, because the insurance is so expensive and also, the fifth wheel on it needs some work.
Copper aluminum radiator is a sheet of radiator with copper lines and aluminum fins. I got $1.49 per lb for it. They have to be clear of iron.
Sheet iron I sold for $295 per ton.
Clean copper went for $2.89 per lb, and copper #2 (with solder) went for $2.74 per lb.
Aha! That is the name I was trying to remember. Thanks!
I have used it, and it was the preferred way to remove the enamel from really fine magnet wire. Any mechanical means was more likely to shorten the wire. :-)
An interesting point.
Which I am not, and I don't think that "Iggy" is, either, for the purpose of buying from chemical suppliers. :-)
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