Hello there Building DC motors has sort of become a hobby lately and I'm about to build the best version yet. However, I have a few questions when it comes to the brushes. I salvaged a couple of brushes from an old electric saw that my dad was throwing away but the resistance of those are much too high for what I'm going to use the motor for. The biggest battery I have is at 11.1V so I can't have brushes with a resistance of almost 10 ohms each. I have read that high resistance brushes gives better commutation but still . I also read that carbon graphite brushes can handle a current density of 7 amps/cm^2, which seems low to me. What material are the brushes made of in start motors? (low voltage high current) What do I search for on fleabay if I want brushes with a maximum resistance of 1 ohms each and that can handle a higher current density? Your answers are appreciated as always :) Edit: I've been using copper brushes until now What I've found so far is that Electrographitic and Metal graphitic brushes are good for what I'm going to use them for but there are so many grades that it's hard to find the right ones on ebay (or any at all).