1 Topic by gwfami

  • gwfami
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  • Registered: 2013-03-11
  • Posts: 142

Topic: Lumpy ABS thread

Hi,
When the ABS comes out of the extruder head, it looks kind of lumpy and blobby.  Anyone seen that before and is it a problem?

Thanks,

GWFAMI

2 Reply by wire10ga

  • wire10ga
  • wire10ga
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Re: Lumpy ABS thread

Sounds like the filament has too much moisture in it. Has it been humid lately for you? You need to dry out your filament. Search the site here; there are a few threads on how to do this.

SD2 - Glass Bed, Fans on PCB and Y motor, Custom enclosure
Slicer - Simplify3D

wire10ga's Website

3 Reply by rickq

  • rickq
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  • Registered: 2013-07-11
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Re: Lumpy ABS thread

"lumpy and blobby"

If this is a very regular/repeated lumpy, about every 3/16" or so, it is probably your extruder stepper driver not running the stepper smoothly.  Use "Manual Controls" in Repetier to extrude some material at around 200mm/min and feel the extruder stepper while it is running.  If the vibration is really obvious then that is your issue.

There is a tiny potentiometer on the extruder driver board that you can SLOWLY turn.  In one direction the vibration will lessen.  Keep turning that direction and the extruder will eventually stop.  Basically, you want it running with the least amount of vibration you can get.

As for a proper tool, they can be purchased or fabricated.  If you make it out of a coat hanger using a dremel, then DON'T SLIP.

Search these forums for extruder pulsing for more info.  Officially, there is a proper bias voltage that you can measure and set. But tuning "by ear" is quite common.