working, well almost

So I know that my new heater core works, I did notice that I was still having problems with the idler wheel. I took it off and found some epoxy had spilled onto the outside edge, and was a little bubbled near the bearing. So I cleaned these up and went to put it back on and realized that one problem was the epoxy, the other was the idler was rubbing against the bottom of the geared tooth pulley. So I added another washer to fix the height and now it moves properly. When I reconnected everything I figured this time I would run the heater core through the relay board. Everything was going well until I neared the set point at which there was this strange screeching noise coming from what I thought was the board. Upon looking at it closer I found that the extruder board must be sending something like a square wave to the other board as it nears the set point so that it doesn't overshoot too much. Well as it would get close my homemade heater core must work very differently than their so it would send the relay board into a fit switching the relay so fast it would sound like screech. Guess I'll just have to run it through the extruder board again, so much for trying to be nice to the board.