help with homemade fans

[Byrok]

I was wondering how many 9 volt batteries you need for 1, 12 volt fan.

[neo71665]

one batt will work. two will too but it will burn the fan up (over time) and be loud as hell, from the fan spinning so fast. one will be a little slow but you wont even notice unless you hook the fan up to a 12v power supply.:crazy: