Re: Skipping with Direct Drive Extruder

[danman]

If you are running 1.75mm, then direct drive should have enough torque to push the filament. 

Without knowing more of the history, here is what I would check: 

1. Did some debris clog the extruder? Heat the extruder to ~170-190 C and pull out the stuck filament, try again

2. Consider experimenting with a higher extruder temperature in 5-10 degree increments - it's possible that your thermistor is not reporting an accurate temp and the filament is not hot enough to extrude correctly

3. If you are having a symptom where the extruder works fine for some period of time like 5-10mins and then quits, it's either that the stepper driver is overheating or you have an extruder barrel heat problem.

Extruder barrel heat problem:

 i.e. if the cold portion of the extruder is inadequately cooled, then heat will slowly expand from the hot end up the barrel. As the heat travels up the barrel, the "soft and sticky" zone for the filament lengthens to the point where no amount of torque will push the filament through the extruder (the torque required is greater than the force that the filament can transfer). The solution for this sort of heat problem is to find any way you can to cool the barrel - if you have a good fan and it is still not working, consider purchasing a new hot end.

Stepper problem: 

- check the stepper voltage to insure it is not too high and causing the stepper driver to overheat

- swap out the stepper driver in case it has marginally gone bad

4. Stepper  voltage tool low: check the voltage on your stepper driver for the extruder - low voltage can cause inadequate torque

(see directions here: http://reprap.org/wiki/Pololu_stepper_driver_board)

On Monday, October 5, 2015 at 6:57:13 AM UTC-7, Blake O'Brien wrote:

Recently, I've noticed my extruder stepper has been skipping steps when extruding PLA. I use a direct drive extruder (which you may find here), so I believe this issue is being caused by a lack of torque. So, what would you suggest? My thought would be to switch to a Wade's style extruder, but should I take this route?