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 months ago (1 children)

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

[–] Nougat@fedia.io 30 points 2 months 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 months ago* (last edited 2 months 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 months ago* (last edited 2 months 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 months ago* (last edited 2 months ago)

It’s definitely a motor brush.

Yep. Here's an example.

[–] neidu3@sh.itjust.works 5 points 2 months 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 months 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 months ago (2 children)

But it is in fact a carbon brush nonetheless

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

Quality reply! Appreciate you taking the time. :)

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

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

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

Never to late to learn!

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

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

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

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

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

Every brush is a carbon brush.

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

And how do you make steel?

[–] clb92 6 points 2 months ago* (last edited 2 months 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 months ago (1 children)

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

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

Woah, I didn't even know. Thanks! 😁

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

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