this post was submitted on 21 Jul 2025
81 points (97.6% liked)
What is this thing?
7127 readers
163 users here now
Let us help you identify that mysterious object you’ve found.
Currently in CHALLENGE mode: If you've got something obscure knocking about, post a picture, and let's see how we do. Please prefix such posts with "CHALLENGE:" so we know we've got a fighting chance.
founded 2 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
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.
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.
To be fair, I'm only "right" pedantically. 😂 My understanding is rocks and minerals aren't mostly carbon, but still contain it...
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.