carbon

so, carbon melts at over 6000 degrees F, and as you can see below my torch is melting it. Actually the pictures are all shortly after turning it off. Nonetheless, I estimate the temperature is more like 9000 degrees, based on the research I've done. This is actually hot enough to vaporize the carbon. Some further trivia, these rods are elementally the same as diamond, and this is one technique they use to create fullerenes, carbon nanotubes, and such.

I started out sharpening the carbon in a pencil sharpener, though for the positive side, that just caused faster melting. My advice is only sharpen one side, especially with a dc powersupply.
I found an excellent source of carbon, hopefully it will show in the attached image. I just cut open a 1.5 volt heavy duty battery and found 4 cells inside, each with it's own carbon rod. I got this battery out of a recycle bin. I think anything that says Heavy Duty, or Extra Heavy Duty will work, and EverReady is a popular brand. Expensive batteries have different reactions going on and don't have any carbon.