I know I need to use a fan for my hot-end to help prevent the barrel from pushing out of the ptfe and PLA from jamming. The problem is where should the fan be aimed? I set up the hot-end and tried to aim a fan at the PTFE but it still felt fairly warm to the touch, and the hot-end would not heat above 140 degrees. I know it can heat up more than that because when the fan is not on I can easily heat it to 200 degrees and probably higher.
Yes - and as far as I know, this is primarily for J-Head not ends. Also, the fan need not be powerful. The heat builds up from convection, so all you need to do is disturb the air enough to break up the rising heat.
