Quote Originally Posted by old man emu View Post
1. If the fan you are talking about is the fan blowing on the extruder head, disconnect the fan from the RAMPS board and connect it directly to either one of the power input points from your power supply. That way, the fan will always be on and the temperature of the extruder will stay constant.

2. If it is the stepper motor that is heating up, then there is too much current going through it. You will have to adjust the variable resistor. Look here ( http://3dprintboard.com/showthread.p...formance/page2 ) for discussions about doing that.


3. For your problem with the printer bed, it is not getting enough current. Get a 12V horn relay from an auto shop and wire the relay between your power supply and bed. Use connections from D8 on the RAMPS board to switch the relay on and off.
DO NOT PUT A RELAY BETWEEN THE POWER SUPPLY AND EXTRUDER HEAD. You'll end up frizzling your Arduino board.

Old Man Emu



Thank you for the advice with the fan. I will definitely do that.

I have adjusted the current on the stepper drivers. I have it as low as I can go with out it stopping extrusion. I can print PLA for 10 hours with out getting anywhere near as hot.