There are two main methods for removing enamel, formvar, and other coatings from magnet wire: mechanical stripping and heat.

The mechanical method uses a (usually) 3-blade rotary tool that strips off the coating by cutting it off as it is pulled out of the tool. You can get one for about 60 bucks, sometimes a bit less, bit also a lot more for high volume commercial solutions.

The heat method uses either a thermal stripper of the kind used for PTFE insulated wire, or more commonly a heated bath like the Eraser Dip Strip product and its melting pot. The Dip Strip is a caustic salt that melts at about 250℃ and is usually used at about 400℃. The wire is dipped into the molten salt for 2-5 seconds depending on the insulation material, and it melts off.

I have personally had some success with an ordinary solder pot using 60Sn/40Pb alloy for some types. You can turn up the temperature to higher than would be used strictly for tinning to make it work better.

For both of these methods you will be dealing with fumes, very hot caustic material or molten metal, and potential for splashing if moisture is introduced. Unless you are doing a large volume, the mechanical method is the most sensible one. Larger gauge wire is not too much trouble, but with really fine gauge stuff you might have to resort to a method that uses heat.

 

I was puzzled about the "aspirin" suggestion until I read the description: "Must be rude, strong natural aspirin from russia or it satellite countries where it is still in use. One tablet may clean several tens of wire ends. " That sort has not been available in the USA for at least 50 years.

 

I know this is an old thread, but I would go with acetone. You can buy it right next to women's nail stripper.

 

Here is a puzzle: Often an old thread will appear in my emails and when I open the thread I get an announcement that it has been over a year. This time that did not happen, and yet the discussion stopped in late December 2021.
What was different this time????

 

The aspirin is just plain un-coated aspirin. If all you can get is coated aspirin go ahead and crush it.

 

I was puzzled about the "aspirin" suggestion until I read the description: "Must be rude, strong natural aspirin from russia or it satellite countries where it is still in use. One tablet may clean several tens of wire ends. " That sort has not been available in the USA for at least 50 years.

Yeppp, I myself had not been able to buy pure aspirin anymore in apothekes, only that microcellulosae mixed sort. And then I got in Ukraine Lviv (before the war) and see that packet with 6 tablets cost 0.4 cents in the course of exchange. I asked do I can buy the 1000 packets. The apotheke lady said, they have only 100 in stock - so I bought every the last. So for my life will be enough to clean the wires. RE: Dick Cappels : ``The aspirin is just plain un-coated aspirin. If all you can get is coated aspirin go ahead and crush it.``
Wonder if so easy will happen. In Europe at us the nowadays aspirin is nano-mixed 10% aspirin acid with 90% of microcellulosae to get kilo-price and mega-interest for factory. BUT the chemical shops like sigma aldriht and many more sells for rather acceptable price the acetilsalicyl acid in powder form in kilogram sized packs, so, its with nothing worse a medical tablets. Just buy and crop like a cocaine on the wood piece (only never sniff it!), just in the wire-end placement must happen the small melted aspirin acid "lake".

 

RE: Yaakov and mechanical methods:
1) sandpaper number 800-2000. But not applicable to very tiny wires like under 0.1 mm.
2) sliding scalpel against the thumb. Transversally of course, to not cut in the flesh. Good method but when wire count is several tens, then copper particles drift into skin deep and that is painful and probably toxic. May do when only few wires must be cleaned.
3) take the most hated and unuseful pincet, even mild-steel sorts are applicable. With strong plyers bend the ends 90 degrees one against another and sharpen like knife. Adjust them both to look gapless straight one against other. For conveniance of self-centering the wire, sliff with a micro-rasp the middle about 0.1 mm deeper but still sharp. Use this instrument like a finger with scalpel. But it badly works when wire is very tiny, like 0.06 mm or so. But it is magnificent in scale 0.3...1.0 mm and for oxidized resistor legs cleaning before soldering.

 

Here is a puzzle: Often an old thread will appear in my emails and when I open the thread I get an announcement that it has been over a year. This time that did not happen, and yet the discussion stopped in late December 2021.
What was different this time????

It’s no puzzle, Bill. Someone else posted and the post remained. Much of the time the thread was awakened by a spammer, and their post has been deleted.

RE: Yaakov and mechanical methods:
1) sandpaper number 800-2000. But not applicable to very tiny wires like under 0.1 mm.
2) sliding scalpel against the thumb. Transversally of course, to not cut in the flesh. Good method but when wire count is several tens, then copper particles drift into skin deep and that is painful and probably toxic. May do when only few wires must be cleaned.
3) take the most hated and unuseful pincet, even mild-steel sorts are applicable. With strong plyers bend the ends 90 degrees one against another and sharpen like knife. Adjust them both to look gapless straight one against other. For conveniance of self-centering the wire, sliff with a micro-rasp the middle about 0.1 mm deeper but still sharp. Use this instrument like a finger with scalpel. But it badly works when wire is very tiny, like 0.06 mm or so. But it is magnificent in scale 0.3...1.0 mm and for oxidized resistor legs cleaning before soldering.

Yes, I use knives in a pinch—but even for gauges big enough not to immediately break while attempting it, I have had too many cases where elongation or nicking has lead to failures later.

So, I do try to avoid that. I was wondering, though, about the possibility of designed a 3D printable vernier adjustable, or spring tension thingy that could be dialed in the way the commercial rotary tools allow. It could use cheap utility blades or craft knife blades, or something like that. I have to think about it.

 

MisterBill2: ``Here is a puzzle: Often an old thread will appear in my emails and when I open the thread I get an announcement that it has been over a year``
Probably I was those started to "kick a dead", sorry. But it show a first few upper positions on the forum timeline so I have no a habit to inspect always when the first post is printed. I am sure the problem is in software algorythm - one fresh post on the 100 years old original post means it stands a timeline first freshest.

 

It's an old thread which i bumped into, but i am quite surprised that no definite answer has been discussed. Makers in India are quite familiar with a solution available for chemically stripping enamel from copper wire. It's called E-sol, but use is limited to production units . I'll post a link to one seller below. There are more than one manufacturers, and other brands also being sold. I've used it and it surely works! No comments on its safety profile. No idea what it contains, and that's exactly what i was trying to find today when i came across this thread.

https://bhallachemicals.com/product/esol-copper-wire-enamel-remover/

 

It's an old thread which i bumped into, but i am quite surprised that no definite answer has been discussed. Makers in India are quite familiar with a solution available for chemically stripping enamel from copper wire. It's called E-sol, but use is limited to production units . I'll post a link to one seller below. There are more than one manufacturers, and other brands also being sold. I've used it and it surely works! No comments on its safety profile. No idea what it contains, and that's exactly what i was trying to find today when i came across this thread.

https://bhallachemicals.com/product/esol-copper-wire-enamel-remover/

The contents of the bottle is right there in the picture that you linked to: Methylene Chloride and Phenylic Acid. A quick google search result is that it is used in paint stripper.

 

Post #41 covers how I have done it, usually with AWG 14 or 16 wire. The mechanical method was leaving fine copper flakes with the removed insulation so we used a blow torch to burn it off and after heat a cold wet rag to remove the coating.

Ron

 

I take an un-coated aspirin tablet and melt a spot in the tablet being my soldering iron, pulling the wire through the puddle. Avoid breathing the fumes because they hurt!

 

chatgpt gives me this

Removing enamel insulation from magnet wire can be done in several ways, depending on the specific application and available tools. Here are some of the most common and effective methods:

1. Using Heat (Flame or Soldering Iron)

Flame Method:

• Step 1: Hold the magnet wire in a pair of pliers, leaving the enamel-coated section exposed.
• Step 2: Carefully use a flame, such as a lighter or a small torch, to heat the wire. The heat will cause the enamel to burn off.
• Step 3: Once the enamel starts to melt or burn, quickly wipe the exposed wire with a rag or use pliers to scrape off the remaining residue.
• Caution: This method can create smoke, so work in a well-ventilated area and avoid inhaling fumes.

Soldering Iron Method:

• Step 1: Heat a soldering iron to the appropriate temperature (around 350°C or 660°F).
• Step 2: Touch the soldering iron tip to a small section of the magnet wire.
• Step 3: The heat will melt the enamel, and you can use a rag, paper towel, or steel wool to wipe off the enamel.
• Note: This method is less likely to burn the wire but still requires care to avoid damage.

2. Chemical Strippers

Certain chemical compounds can dissolve the enamel without damaging the copper wire underneath. Look for a product designed specifically for removing enamel from magnet wire.

• Step 1: Apply the stripper according to the manufacturer’s instructions, usually by dipping or applying with a brush.
• Step 2: Allow the chemical to work for several minutes.
• Step 3: Wipe or scrape off the enamel.

Popular chemical removers include:

• Nitric acid (commonly used for removing enamel)
• Paint strippers (some types are effective on enamel)
• Specialized enamel removers (available in electronics or wire-working supply stores)

3. Mechanical Methods

Using abrasives can also help remove the enamel from the wire.

• Steel Wool or Sandpaper: Gently rub the wire with fine steel wool or sandpaper (preferably 400-grit or finer) to strip away the enamel.
• Rotary Tool (Dremel or similar): You can also use a rotary tool fitted with a small sanding drum or wire brush attachment to carefully remove the enamel.

Caution: Mechanical methods can damage the wire or leave tiny abrasions on the surface, so use them carefully.

4. Soaking in Acetone or Nail Polish Remover

For some types of enamel, soaking the wire in acetone or nail polish remover can soften and dissolve the coating over time.

• Step 1: Submerge the wire in acetone or a similar solvent for several hours or overnight.
• Step 2: After soaking, use a soft cloth or abrasive pad to wipe off the softened enamel.
• Step 3: Dry the wire and ensure there is no remaining residue.

5. Mechanical Stripping Tools

There are dedicated wire stripping machines or hand tools designed to remove enamel from magnet wire efficiently. These tools often work by feeding the wire through a series of abrasive rollers or using a heated blade to strip the insulation.

• Use case: Best for bulk wire stripping in industrial or high-volume applications.

Choosing the Best Method

• For small amounts of wire: The heat or soldering iron method is quick and effective.
• For larger quantities or precision: Chemical strippers or mechanical wire strippers are often better.
• For delicate or thin wires: Be careful with flame methods, as excessive heat can damage or break the wire.

Always take safety precautions, including working in a well-ventilated area, wearing protective gloves, and ensuring the work surface is flame-resistant if using heat.

 

In my experience, using acetone works with in seconds not overnight.

 

At one time enameled wire was available with insulation called "Polythermaleze" (I may have the spelling a bit wrong). That wire insulation vanished with the heat of soldering. At least THAT was the claim.