Hi there

I've recently purchased and completed building the Prusa i3v 10". It's my first personal 3D printer, and I love everything about it so far.

I have a couple questions:
1) When printing ABS, the bed starts at 110 °C but after the first couple layers, the bed drops in temperature to around 70 °C. Is this normal? My ABS prints are having issues sticking to the bed, and I'm wondering if this may be part of the issue.

2) What's the safest way to install a power switch to work with the 12V/30A power supply? I don't want to accidentally fry any of the electronics, but I don't want to have to keep plugging and unplugging the power supply from the wall when I use the printer.

3) Is 10 awg wire too thick to wire FROM the power supply to the necessary inputs on the printer electronics?

Thanks in advance!