Brush from an electric motor. Looks to be a new-ish one.
this post was submitted on 21 Jul 2025
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What is this thing?
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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
Looks like the piezo-electric igniter from a lighter. Either that, or what GreyShuck said - A carbon brush from a motor.
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
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.
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....
But it is in fact a carbon brush nonetheless
What are their purposes?
The brushes glide along the commutator and transmit the electric current to the rotating armature (Anker) in the motor.
This is the first time I've bothered learning about this. Thanks!
Never to late to learn!
Quality reply! Appreciate you taking the time. :)
Aha, thanks. I wonder how it ended up in a park.
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.
To make an electrical connection to a moving (rotating) part.
Every brush is a carbon brush.
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.
To be fair, I'm only "right" pedantically. 😂 My understanding is rocks and minerals aren't mostly carbon, but still contain it...
And how do you make steel?
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)
Well, you take iron ore, heat it up, and add, uh...
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.
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.
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.
Happy cake day!
Woah, I didn't even know. Thanks! 😁
Lots of smaller brushed motors use brass or bronze brushes. Slower moving mechanisms use a variety of materials.