this post was submitted on 21 Jul 2025
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What is this thing?

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It looks like some sort of wiring inside

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[–] GreyShuck@feddit.uk 106 points 2 weeks ago (1 children)

Brush from an electric motor. Looks to be a new-ish one.

[–] Nougat@fedia.io 30 points 2 weeks ago

Could be from a destroyed power tool, or discarded from an alternator or starter rebuild.

https://www.amazon.com/General-Electric-59G-Brush-Motor-AK-Motor-Brush/dp/B01F818V7Y

[–] neidu3@sh.itjust.works 4 points 2 weeks ago* (last edited 2 weeks ago) (2 children)

Looks like the piezo-electric igniter from a lighter. Either that, or what GreyShuck said - A carbon brush from a motor.

[–] clb92 24 points 2 weeks ago* (last edited 2 weeks ago) (2 children)

It's definitely a motor brush.

I've never seen a piezoelectric igniter that looks anything like what OP posted. Just to be clear, you're talking about these that are in most lighters, right?

Image of piezoelectric igniter

[–] AFKBRBChocolate@lemmy.ca 6 points 2 weeks ago* (last edited 2 weeks ago)

It’s definitely a motor brush.

Yep. Here's an example.

[–] neidu3@sh.itjust.works 5 points 2 weeks ago

Yes. There's one variant that looks more similar to Ops picture, but I haven't seen it around in ages. But the wire inside the spring is more indicative if a motor brush.

[–] givesomefucks@lemmy.world 7 points 2 weeks ago (1 children)

piezo-electric igniter from a lighter

Waaay more likely to be laying around in the ground outside too.

Like, I can't recognize a brush on sight, but I would be shocked if they looked identical to a common switch found in cheap electric lighters....

[–] PyroVK@lemmy.zip 28 points 2 weeks ago (2 children)

But it is in fact a carbon brush nonetheless

[–] givesomefucks@lemmy.world 11 points 2 weeks ago (1 children)
[–] whaleross@lemmy.world 3 points 2 weeks ago (2 children)
[–] Successful_Try543@feddit.org 14 points 2 weeks ago (3 children)

The brushes glide along the commutator and transmit the electric current to the rotating armature (Anker) in the motor.

https://upload.wikimedia.org/wikipedia/commons/5/5b/MotorCommutator.jpg?20071230191926

electric motor

[–] BorisBoreUs@lemmy.world 5 points 2 weeks ago

Quality reply! Appreciate you taking the time. :)

[–] Gerudo@lemmy.zip 5 points 2 weeks ago (1 children)

This is the first time I've bothered learning about this. Thanks!

[–] Akasazh@feddit.nl 4 points 2 weeks ago

Never to late to learn!

[–] whaleross@lemmy.world 3 points 2 weeks ago (1 children)

Aha, thanks. I wonder how it ended up in a park.

[–] Onomatopoeia@lemmy.cafe 4 points 2 weeks ago

Fell out, either from a destroyed tool or simply fell out, as they're held in with a simple screw cap.

Could've also fallen/dropped by someone who repairs such things, as it's sometimea an easily replaceable part.

[–] zout@fedia.io 7 points 2 weeks ago

To make an electrical connection to a moving (rotating) part.

[–] Empricorn@feddit.nl 6 points 2 weeks ago (3 children)

Every brush is a carbon brush.

[–] clb92 7 points 2 weeks ago (2 children)

A steel wire brush isn't.

I was initially going to say "my hairbrush isn't", but I forgot plastic is largely made of carbon, so you's still be right.

[–] Empricorn@feddit.nl 3 points 2 weeks ago

To be fair, I'm only "right" pedantically. 😂 My understanding is rocks and minerals aren't mostly carbon, but still contain it...

[–] Davel23@fedia.io 3 points 2 weeks ago (2 children)

And how do you make steel?

[–] clb92 6 points 2 weeks ago* (last edited 2 weeks ago)

And how do you make steel?

I don't. I have people to do that for me.

(But to answer your question, with a small amount of carbon, sure, but in my opinion that doesn't mean that steel is "made out of carbon" any more than we would say humans are made out of iron)

[–] threelonmusketeers@sh.itjust.works 3 points 2 weeks ago (1 children)

Well, you take iron ore, heat it up, and add, uh...

[–] Successful_Try543@feddit.org 1 points 2 weeks ago* (last edited 2 weeks ago) (1 children)

As iron, unlike gold isn't a noble metal, an important aspect is, you need carbon to make ~~pure~~ iron from the iron oxides in the iron ore: The carbon will react with the oxygen and ~~pure~~ elementary iron and carbon oxides are left.

[–] threelonmusketeers@sh.itjust.works 1 points 2 weeks ago (1 children)

Pure iron is somewhat soft. To make steel, you typically add extra carbon to the iron, which results in a harder (though more brittle) metal.

[–] Successful_Try543@feddit.org 2 points 2 weeks ago* (last edited 2 weeks ago)

Essentially, you reduce the carbon content of the raw iron by blowing in oxygen until you have the desired amount of carbon left. I should have written 'elementary' iron instead of pure.

[–] threelonmusketeers@sh.itjust.works 5 points 2 weeks ago (1 children)
[–] Empricorn@feddit.nl 2 points 2 weeks ago

Woah, I didn't even know. Thanks! 😁

[–] XTL@sopuli.xyz 3 points 2 weeks ago

Lots of smaller brushed motors use brass or bronze brushes. Slower moving mechanisms use a variety of materials.