Use 12v fans for your ESC/motor...

[BrianG]

@AAngel: The insulator is used because the metal tab on many regulators is electrically the same point as the output of the IC. So, if you don't use it, the heatsink (and the shole chassis if you use the chassis as a heatsink) will be floating at 12v.

The pad I used is some kind of mica part that is electrically insulative, but thermally conductive. It's not really an ideal thermal conductor, but given the heat levels for this "circuit", it is more than adequate. I'd rather trade off a tad bit of thermal performance for the electrical insulative properties, especially since we dealing with power losses on the order of less than 1w.

@Dafni: I'm sure most fans have a working range. I just get real anal about running them (and anything really) higher than rated.