Carbon Brushes are Graphite right?

[Panthera Leo]

Carbon Brushes are Graphite ... right?

I was wondering if the carbon brushes are graphite? and if yes how pure?
These days I am in Sri Lanka and can't find any seller offering pure graphite tubes, to be used as a heating element.

So I though what if... I could use these carbon brushes instead as a cheap & fast alternative until I get one from abroad... lol

It's not a cleaver thought but any chance it could work?!

Thanks in advance

 

[sophiecentaur]

What resistance do you need? By design, brushes are short and fat and have as low a resistance as possible. A heating element needs to have high enough resistance to dissipate the power you require.- hence, long and thin (ish).

 

[and7barton]

Brushes are not pure graphite, by a long way - They are a mixture of carbon, graphite and a collection of binders to "glue" them together. They are baked (sintered) during manufacture. When they are running inside a motor, some of those other chemicals are liberated and act as a lubricant between the brush and the commutator... one of those lubricants, I believe, is plain old water.

 

[sophiecentaur]

Did you think about getting carbon rods out of old D type cells?
http://www.youtube.com/watch?v=oN21ELKEIns

 

[RocketSci5KN]

I wonder if a thick pencil core would work?

 

[sophiecentaur]

Yes, in principle - I have done it. You need to specify how much power you want and what your operating voltage will be before you can expect a quantitative answer but you can definitely get a pencil lead too hot to touch!