I broke the positive wire lead off my Novak GTB ESC.

I just tried to remove what remains of the old wire from the ESC with my soldering gun ( HAKKO ).

It seemed like the material the ESC was made of was absorbing all the heat away from my soldering tip. So much so that I couldn't even remotely soften the old solder.

Has anybody tried to repair these ESC's before? If so what did you have to do? Or am I just that inept with a soldering gun?

Any tips are appreciated.