What dissolves / removes magnetic wire enamel / coating ? - Page 1
Forum section: electronics / beginners

author: lordvader88
author_rank: Frequent Contributor
timestamp: March 24, 2018, 02:16:46 am
content: I hate trying to sand the ends off mag. wire, especially fine stuff. Is there a common solvent that usually works on average cheap coated copper wire?

author: BravoV
author_rank: Super Contributor
timestamp: March 24, 2018, 02:24:02 am
content: Acetone.

author: Rog520
author_rank: Regular Contributor
timestamp: March 24, 2018, 03:04:04 am
content: Depends on what the wire is coated with. Basic enamels and polyurethanes are best stripped with solder and flux. More durable insulations like polyimide require mechanical or chemical stripping. Molten sodium hydroxide (lye/drain cleaner) works well...just be very careful to do it under a fume hood or outside with plenty of ventilation (i.e. don't breathe the fumes!).

author: joeqsmith
author_rank: Super Contributor
timestamp: March 24, 2018, 03:25:24 am
content: An eraser. Not the kind you have on a pencil. It's similar to a centerless grinder. I've used one a fail amount and it works well.

author: joeqsmith
author_rank: Super Contributor
timestamp: March 24, 2018, 03:28:20 am
content: Also, even for fine wire, at home I have resorted to holding it onto the ESD mat and dragging the X-acto blade over it. Hold the knife so the brake is dragging over the wire, not cutting into it. This is a bit of a pain. If you do it a lot, the eraser.

author: MasterT
author_rank: Frequent Contributor
timestamp: March 24, 2018, 04:53:10 am
content: Aspirin, press wire to a pill by hot iron.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: March 24, 2018, 05:25:34 am
content: At room temperature? Methylene chloride?At high temperature, soldering heat does it, for "Sold-Ez" types.Ask the manufacturer, it varies by formulation. Some high temperature enamels (polyimide based) have to be removed mechanically, or chemically with some very unsavory substances.If nothing else, if you find you need fire -- fire leaves scale (copper oxides). These can be removed with a strong flux (usually acid), but acids cause corrosion later. I find it's better -- and much more exciting (wear PPE) -- to use a spoonful of molten NaOH. This melts around the melting point of lead, and forms salts of everything involved (lead and tin oxides dissolve, forming the respective {plumb|stann}{ite|ate}, while copper oxide becomes the strongly blue sodium cuprate; metal particles floating around tend to turn the melt gray or black, though). Quench the wire in water and soak until the lye and salts are completely dissolved. Do not get NaOH in your eyes if you want to keep them; melt can spatter, quenching NaOH releases fumes; etc. All the usual stuff.Quote from: BravoV on March 24, 2018, 02:24:02 amYikes! Your wire has terrible enamel, for your own sake dispose of it and buy new!Tim

author: Brumby
author_rank: Unknown
timestamp: March 24, 2018, 06:05:12 am
content: Quote from: joeqsmith on March 24, 2018, 03:28:20 amYep. I'm a scraper, too.

author: lordvader88
author_rank: Frequent Contributor
timestamp: March 24, 2018, 01:03:32 pm
content: This is dissapointing

author: Brumby
author_rank: Unknown
timestamp: March 24, 2018, 01:13:00 pm
content: I think I am like most others, for the quantity of work that I do with such wires, the simple mechanical scrape is the easiest option.If I was doing 20 a day, I'd probably look for something faster - and if I was doing 100, I certainly would.

author: joeqsmith
author_rank: Super Contributor
timestamp: March 24, 2018, 02:18:04 pm
content: Quote from: lordvader88 on March 24, 2018, 01:03:32 pmEraser cost too much? If you are not sure what I was referring to, marketing clip..https://youtu.be/KyDjcNE1090

author: SeanB
author_rank: Super Contributor
timestamp: March 24, 2018, 02:34:22 pm
content: When I was doing a lot of windings I went and got a pair of cheap plastic tweezers, and took some 1000 grit waterpaper and superglued it to the jaws, then cut to the shape of the jaws. To use simply grip the wire in the tweezers lightly and pull, it strips the enamel enough to solder perfectly then. Worked from 22SWG to 48SWG enamelled wire no problem. For another I had to clean corrosion off the inner terminal, recessed deep in a housing, some 200 grit waterpaper superglued to a bit of shafting ( the guide rod from a old 5.25in Floppy drive was the right diameter and long enough to reach down, plus had a turned flat end both sides) fitted down there and was easily able to clean off the green gunk there.

author: RoGeorge
author_rank: Super Contributor
timestamp: March 24, 2018, 02:35:18 pm
content: Aspirin, also known as acetylsalicylic acid (ASA) can disolve enamel when heating with a soldering iron.https://en.wikipedia.org/wiki/AspirinI used to use this trick back in the days, but it has a terrible, terrible smell.Be aware that bad smells usually means toxic, or other kind of health hazard.

author: lordvader88
author_rank: Frequent Contributor
timestamp: March 24, 2018, 06:59:10 pm
content: Well I might try acetone/nail polish removerIn the meantime I should try finer grit spthe tweezers plus sp is a good idea too, easy to improvise from scraps

author: Crazy_Engineer
author_rank: Contributor
timestamp: March 25, 2018, 01:10:23 pm
content: For smaller amounts of wire I have always cranked up the heat on my soldering iron to melt it off. If that failed or it was a large amount of wire acetone was my next tool.

author: BrianHG
author_rank: Super Contributor
timestamp: March 25, 2018, 01:28:52 pm
content: For the really thick high tension wire, use the 45 degree angle metal wire polish/scraping brush on your dremel drill tool. It removes the enamel instantly like a magic eraser, no chemicals, no fumes, just clean easy to solder bright copper remains. For the smaller/thinner wires, just turn up the temperature of your weller.As for the other hot method, one of my custom local transformer/toroid manufacturer used to have a hot solder pot. (Don't remember what they are called). It was just hot enough, much more than a weller, the guy at the manufacturer just dipped the ends of the transformer wires in the pot filled with molten lead and the enamel vanished/bubbled away instantly.

author: tautech
author_rank: Super Contributor
timestamp: March 25, 2018, 01:43:52 pm
content: BrianYou're on the money....a solder pot.Couldn't believe it took so long for somebody to mention this.And they're cheap:https://www.aliexpress.com/wholesale?catId=0&initiative_id=SB_20180325054251&SearchText=solder+pot

author: BrianHG
author_rank: Super Contributor
timestamp: March 25, 2018, 01:49:43 pm
content: Quote from: tautech on March 25, 2018, 01:43:52 pmLordvader needs a 120v version. Go for the high power 300watt version:https://www.amazon.com/100mm-Solder-Capactity-Welding-Soldering/dp/B076M2BCPQ/ref=sr_1_2_sspa?ie=UTF8&qid=1521985750&sr=8-2-spons&keywords=solder+pot&psc=1A smaller 150watt version:https://www.amazon.com/50mm-Solder-Capactity-Welding-Soldering/dp/B074K3GVQM/ref=sr_1_1_sspa?s=hi&ie=UTF8&qid=1521986241&sr=1-1-spons&keywords=solder+pot&psc=1Plus a bar of solder:https://www.amazon.com/40-Lead-Solder-Made-RotoMetals/dp/B001QUZ6W0/ref=sr_1_5?s=hi&ie=UTF8&qid=1521985935&sr=1-5&keywords=Bar+SolderDon't forget flux...

author: mikemxyzzy
author_rank: Contributor
timestamp: March 25, 2018, 04:03:20 pm
content: There are tools made for this:https://www.knipex.com/index.php?id=1216&L=1&page=group_detail&parentID=&groupID=1390Knipex part #15 11 120

author: Neomys Sapiens
author_rank: Super Contributor
timestamp: March 26, 2018, 12:08:49 am
content: Quote from: mikemxyzzy on March 25, 2018, 04:03:20 pmI was scrolling all the way down, and since halfway I wondered if I have to tell them first about the Lackabziehpinzette.Also here (Vomm):https://www.weidinger.eu/shop/werkzeuge/pinzetten/vomm_pinzetten/vomm_pinzetten_fuer_spezielle_anwendung/wl26792or here (Bernstein):https://www.amazon.de/dp/B00IOHIUFI/ref=asc_df_B00IOHIUFI51133689

author: kg4arn
author_rank: Unknown
timestamp: March 26, 2018, 09:09:40 am
content: I use the Knipex tools.

author: dhutch
author_rank: Newbie
timestamp: August 12, 2020, 10:21:44 am
content: Put the enamelled copper wire in 98% sulphuric acid for 10 minutes. The coating lifts and floats away.

author: jpanhalt
author_rank: Super Contributor
timestamp: August 12, 2020, 11:32:00 am
content: "Enameled" magnet wire is not a single entity. There is a variety of coatings, some are harder to remove than others. For the solderable versions, it is usually not problem. For the non-solderable versions, a molten salt bath can be used. There used to be a commercial version of that. I am not sure it is still available.I took a small steel block, bored a 1/2" to 3/4" hole, and used a mixture of NaOH and/or KOH with a little NaNO3. (ratio 4:1).At about 300° to 325°C the insulation is cleanly removed. The wire may darken quickly when removed, but is still easily soldered without further treatment.

author: Psi
author_rank: Super Contributor
timestamp: August 12, 2020, 11:40:49 am
content: Unless you are winding transformers, motors or something that runs hot.. throw that wire in the rubbish bin and buy the type where the coating can easily be burnt off just by touching it with the iron tip and some solder.Using the type where you have to use sandpaper, or scrape with a knife, is just too annoying to be bothered with.When it comes to enameled wire, even with the kind that is removable by soldering there are different grades. Some are still annoying while others very easy to remove. so YMMVFor super fine wire the roadrunner stuff is awesome. I don't think they make thicker wire.

author: Ian.M
author_rank: Super Contributor
timestamp: August 12, 2020, 12:05:59 pm
content: Of course there's alwaysFOOF, which will dissolve any wire varnish or insulation except pure PTFE. It has the minor disadvantage that it also explosively decomposes the wire, lab bench, technician and nearly all other nearby substances, which would make a dip pot of the stuff excessively 'interesting' (in the curse sense) even if you can cope with the need for cryogenic cooling of the pot.https://blogs.sciencemag.org/pipeline/archives/2010/02/23/things_i_wont_work_with_dioxygen_difluorideMuch of the joy is in the comments!

author: Psi
author_rank: Super Contributor
timestamp: August 12, 2020, 12:08:28 pm
content: Chlorine tri-fluoride would also probably remove the coating. Doesn't mean it's a good idea.

author: Dulus
author_rank: Contributor
timestamp: August 12, 2020, 02:28:54 pm
content: I'm surprised that so little people suggested fire.Baptize the damn thing with fire .!Most of my comments below are made for "low quantity lab use".For large amount of work, a hot solder pot with an aggressive flux dip is the key.Just keep a lighter around.Most of the coatings can be burnt away with hot iron burnts to a molten bulb of slag and broken off after it cooled.And even the temperature resistant ones lose their elasticity and become somehow brittle after the beforementioned baptism.Than you can scrape those away with an almost sharp object.Oxide layer either can be cleaned mechanically afterwards, or if not too severe, left there for flux to handle.Also, inside edge of metal tweezers are quite good for scraping the enamel.Most tweezers edges has just the right sharpness for the job.Pinch it with your thumb and pull. Turn the wire between pulls and voila....Cant imagine having a molten solder pot in the lab or bench all the time.And they take some to heat up.People who suggested molten bath of lye scare me....

author: filssavi
author_rank: Frequent Contributor
timestamp: August 12, 2020, 03:12:15 pm
content: For mass production of electrical machines (hairpin winding, the wire comes per-insulated) they use either mechanical stripping or laser ablation (in order of both price and performance), you can also use just burn the insulation off (with a lighter) however it does a very poor job of it, leaving residues that still hamper solderability, and also gives off toxic fumes.Overall I too think that for lab use you should just throw it in the recycling bin and buy some regular stuff.Edit: I would not go down the chemical path if you don’t know the type of resin used as there are many with very varied composition

author: janoc
author_rank: Super Contributor
timestamp: August 12, 2020, 03:58:14 pm
content: Acetone, sulphuric acid (!!) ... uuugh folks ...For the people who recommend the so called "solderable" enamel (the one which burns off when heated using soldering iron to about 360-380 degrees C), be aware that polyurethane enamels release toxic fumes (isocyanates) when heated. You will need to do it with a good fume extractor, that is really not something you would want to breathe in.

author: BrianHG
author_rank: Super Contributor
timestamp: August 12, 2020, 06:44:51 pm
content: There is an electric tool designed for this:https://www.aliexpress.com/item/32962954758.html?spm=a2g0o.productlist.0.0.37253d7bDYoCKp&algo_pvid=76f1cb5f-de66-4cde-8ee4-1fa014f363b6&algo_expid=76f1cb5f-de66-4cde-8ee4-1fa014f363b6-1&btsid=0be3746c15972582249054995e75e9&ws_ab_test=searchweb0_0,searchweb201602_,searchweb201603_See here:https://youtu.be/bsS_7EEYx1Y?t=1390

author: SilverSolder
author_rank: Super Contributor
timestamp: August 12, 2020, 09:00:30 pm
content: Quote from: joeqsmith on March 24, 2018, 02:18:04 pmThat looks like a cool little device - a kind of inside-out wire brush?

author: KL27x
author_rank: Super Contributor
timestamp: August 12, 2020, 09:18:55 pm
content: A solder pot works a treat. The reason it's different than just burning or using an iron and solder blob, you don't dip the wire, you have to swish the end of the wire in the pot to remove all the gunk leftover after melting. You are melting it and cleaning the wires by swishing it through molten solder as the cleaning agent. Esp on thinner wires, this is important cuz you can dissolve those wires before you get them clean, otherwise.

author: janoc
author_rank: Super Contributor
timestamp: August 12, 2020, 10:42:32 pm
content: Quote from: SilverSolder on August 12, 2020, 09:00:30 pmMore like a sander.However, this is unlikely to be useful for the thin wire commonly used in electronics - it would likely destroy the wire.

author: Psi
author_rank: Super Contributor
timestamp: August 12, 2020, 11:48:03 pm
content: There's so many different grades of coating.Some you can burn off the coating simply by soldering it, others you must sand or scrape the coating off.And all combinations in between.

author: StuartA
author_rank: Regular Contributor
timestamp: August 13, 2020, 07:55:42 am
content: Quote from: jpanhalt on August 12, 2020, 11:32:00 amAs a qualified chemist who has spent quite some time on this subject, I think the above synopsis is right on the money. There are now so many different types of "enamel", you usually have to just find out what works. But for the very toughest coating, often used in the past, the molten salts bath works well when you need the throughput.

author: Analog Kid
author_rank: Super Contributor
timestamp: July 18, 2025, 02:03:56 am
content: Scraping with a sharp knife blade. That's how I do it.Dunno what chemicals would work: probably acetone? But would be messy.

author: antenna
author_rank: Frequent Contributor
timestamp: July 18, 2025, 06:56:14 am
content: I use a lighter on the fine stuff and a butane torch on the heavier wire. Lightly sand with fine sandpaper folded over the wire to clean it up afterward.