Jump to content
Ultimaker Community of 3D Printing Experts

Consistently Under-Extruding


Recommended Posts

Posted (edited) · Consistently Under-Extruding

Ender 5 Pro with a Duet 2 Maestro board, E3D Titan extruder driven by a 0.9 degree motor direct over a E3D Volcano hotend with a 0.6mm NozzleX configured for 3mm filament.

 

I used to run a BMG extruder with a 1.8 degree motor through a bowden tube into a Micro Swiss hotend with 0.4mm nozzle setup for 1.75mm filament. I had the extruder steps/mm set to 420, and that worked perfectly for months. Never had any extrusion issues. I could command 100mm of extrusion through the Duet web control interface, and that's exactly what I got every time. Prints came out perfect, or if they ever failed, it wasn't due to extrusion issues.

 

Now with the new setup, I went through calibration steps and came up with 840 steps/mm, which makes sense since I switched to an 0.9 degree motor. Once again, if I command 100mm of extrusion through the web interface, that's exactly what I get every time at any hotend temperature within 10c from the filament recommendation and at any extrusion speed from 1 to 4 mm/s.

 

But prints from Cura are coming out terrible. There's very obvious under-extrusion throughout. Gaps between lines, fragile infill, holes in the top skin, it's all miserable. If I increase filament flow by 20% through the web interface during a print, the issues mostly resolve themselves, though the top skin still doesn't look anywhere near as nice as it used to with my old setup. But +20% seems like a heck of a bandaid. I'd love to know why Cura isn't asking for more filament flow.

 

I've confirmed that I have the nozzle size set to 0.6mm, and the filament size for the extruder settings is at 2.85mm. The filament itself measures in at exactly 2.85mm and seems consistent. It's a good quality ABS (Polymaker Polylite ABS) and it's dry.

 

What would be appropriate steps to take to diagnose this issue?

Edited by GoremanX
  • Link to post
    Share on other sites
    Posted · Consistently Under-Extruding
    13 hours ago, GoremanX said:

    What would be appropriate steps to take to diagnose this issue?

     

     I would (in unsorted order):

    1. try a different slicer to rule out (or confirm) Cura settings as the cause
    2. disable interpolation for the extruder - leave it untouched for all other axis (config.g M350)
      I had similar experiences with a 3mm DDG extruder, interpolation mode of the trinamic drivers results in a lot less torque of the motor (as far as i understand it) and that may well explain the underextrusion.
      It's working well with "M350 E32 I0".
  • Link to post
    Share on other sites
    Posted · Consistently Under-Extruding
    2 hours ago, tinkergnome said:

     

     I would (in unsorted order):

    1. try a different slicer to rule out (or confirm) Cura settings as the cause

    Good call! Tried it in Slic3r. There's absolutely no under-extrusion when I print a file from there, and I'm not adding any extrusion in firmware. In fact, the top surface came out perfect, no issues whatsoever. I was even able to turn off some of the retraction and pressure advance hacks that I've been using to try to deal with this issue. Slic3r is giving me the kind of print quality with my current setup that Cura used to get me with my old setup. The reason I don't typically use Slic3r is that it doesn't have any enclosure temperature control, and I'm just much more familiar with the Cura workflow.

     

    So now the question is, why is Cura causing so much under-extrusion with my current setup?

  • Link to post
    Share on other sites
    Posted · Consistently Under-Extruding
    7 hours ago, GoremanX said:

    So now the question is, why is Cura causing so much under-extrusion with my current setup?

     

     Could you please provide an example gcode file that exhibits this problem? Thanks.

  • Link to post
    Share on other sites

    Create an account or sign in to comment

    You need to be a member in order to leave a comment

    Create an account

    Sign up for a new account in our community. It's easy!

    Register a new account

    Sign in

    Already have an account? Sign in here.

    Sign In Now
    • Our picks

      • Talking additive | The 3D printing podcast
        Why should we be the only ones asking questions? Join us and ask Jabil all your questions on September 22nd 5pm CET
          • Like
        • 3 replies
      • Ultimaker masterclass: Optimizing your Ultimaker Cura workflow
        Save your seat for either broadcast on September 23.
        What will you learn?
        · Best practices for iterative print preparation and every lesson you should learn from each print
        · The right way to use per-object settings and when they are most useful
        · Easy-to-use resources for anyone who wants to develop their own printer definitions, plugins, or print profiles
        · How to optimize print profile settings and whether to “keep” or “discard” changes
        · When is the right time to export your drawing from CAD? (Based on Ultimaker Cura’s surprising power as 3D control software)
        · And a whole lot more tips and tricks!
         
        How can I join?
        This free masterclass will take place twice:
        1. 11am CEST (5pm SGT, 5am EDT)
        2. 5pm CEST (11am EDT, 8am PDT, 11pm SGT)
          • Like
        • 0 replies
      • Do you use 3D printing at work? Let us know
        It doesn't matter if you are using 1 Ultimaker or 10, there is inspiration in everything. We're looking for ...
        • 1 reply
    ×
    ×
    • Create New...