Kruton,
I tried with a 1/2 spiral bit, the largest one I have. It did great for a while, made a big hole, but then eventually stopped as well.
KnarlyCarl, I haven't seen the charger flash the hot/cold sequence, it either flashes a single light to indicate that needs charging, or if the battery pack sat for a while while I charged the other one, when I put it on the charger the light is solid, as if it's charged.
so the theory that I'm overheating the battery or somehow hitting the load limit makes sense to me. But I still need to drill that hole, what should I do? do it little by little, drill until it stops and then let it rest for a while, or will that damage the drill? Any other tips or tricks?