They dont look or feel isolated, like ones inside a headphone cable

73 points

They’re called enameled cables, they’ve got a thin layer of insulation which prevents them from rusting or shorting.

permalink
report
reply
9 points

To add, enameled wires are also used in motor windings and old CRT monitors (deflector windings). The easiest way to identify it is to scratch with a knife or burn a small portion of the wire to see if the enamel separates.

permalink
report
parent
reply
2 points

What does it look like when the enamal seperates vs a non-enameled wire?

permalink
report
parent
reply
4 points

Slightly brighter and shinier. The enamel gives it a slightly darker matte finish. More importantly though, the peeled/burned enamel looks different from copper.

permalink
report
parent
reply
60 points

I created an account just to answer this. They can short. We had a string of these, and it shorted and nearly caught the tinsel on fire. They weren’t man-handled, in fact we were extra-careful with them, because they were so thin and fragile-looking. These are dangerous. Do not use them.

permalink
report
reply
15 points

The power supplies feeding these are typically .5A at 5v so they can’t draw more than ~2.5w. Is that really enough to generate sufficient heat to start a fire? Maybe if they are wrapped around something incredibly flammable?

permalink
report
parent
reply
21 points

Is that really enough to generate sufficient heat to start a fire?

In case of a short circuit, yes, more than sufficient

permalink
report
parent
reply
6 points

Welcome

permalink
report
parent
reply
3 points

Thank you. :)

permalink
report
parent
reply
48 points
*

There is a nonconductive coating on the wire that also prevents it from oxidizing. The wires can touch, but if the coating isn’t scratched it won’t short.

Some fine grit sandpaper will reveal the metal so you can solder connections.

permalink
report
reply
16 points

will also see it sold as “magnet wire” (for winding your own electromagnets) and the heat from your soldering iron is usually enough to melt through the enamel varnish

permalink
report
parent
reply
13 points

That’s generally not recommended as a way of stripping them though, since the coating is often made of polyurethanes, which release alkyl isocyanates (highly toxic) when heated strongly. While a small amount in a well-ventilated area might not be enough to give you any problems, if you get too much it is very bad. The organic material will also impact the ability to solder. Better to scrape it off first.

permalink
report
parent
reply
23 points

They are all insulated

permalink
report
reply
5 points
*

Yeah, those kinda puzzled me as well. They didn’t look like they’re varnished, but I suspect I could be wrong about that. After all, they do work, lol 😂.

permalink
report
reply
2 points

“Never change something that works”

permalink
report
parent
reply
9 points

It works for now, but the reason most wires have a rubber-like insulator around them is that it takes very little to Crack or abrade a thin coating such as this and turn it into a fire hazard.

I’m surprised a product with such a small safety margin is allowed for sale.

permalink
report
parent
reply
3 points

It works with 2 or 3 AA batteries, not that much power

permalink
report
parent
reply

Technology

!technology@beehaw.org

Create post

A nice place to discuss rumors, happenings, innovations, and challenges in the technology sphere. We also welcome discussions on the intersections of technology and society. If it’s technological news or discussion of technology, it probably belongs here.

Remember the overriding ethos on Beehaw: Be(e) Nice. Each user you encounter here is a person, and should be treated with kindness (even if they’re wrong, or use a Linux distro you don’t like). Personal attacks will not be tolerated.

Subcommunities on Beehaw:


This community’s icon was made by Aaron Schneider, under the CC-BY-NC-SA 4.0 license.

Community stats

  • 3K

    Monthly active users

  • 2.8K

    Posts

  • 55K

    Comments