Jump to content
UltiMaker Community of 3D Printing Experts

overextrusion using 2 extruders (pla with pva)


Recommended Posts

Posted · overextrusion using 2 extruders (pla with pva)

Hi all


i'm a french student in electronical engineering and for my tutorship project i have to print a reflectarray (telecommunication)

this project needs extreme printing accuracy and i have trouble finding the right settings. Also i'm working on a ultimaker S5 with ultimaker PVA and generic PLA 


so the main probleme i have is when printing with pla (AA 0.4) and pva (BB 0.4) to support my structure.

What's happening is that when the printer is changing materials lets say from PLA to PVA ,a bit of PLA is still coming out of the extruder, so when changing again from pva to pla it puts too much materials. I've tried the setting "retract at layer change" but didn't get good results


here is some picture so you can understand better 


So this is a print whith PLA support and i'm pretty satisfied with the quality but wasn't able to remove my structure from the support (it's very thin so it must have melted together) 


so i've tried with PVA but this is when the probleme of overextrusion occured 


as you can see there is some overextrusion when changing material so when changing materiel it create a sort of blobs on the sructure 


here is the strucure after dissolving pva as you can see the quality is far from the first print when using just one extruder 



I've thought about using pla from ultimaker or change the support for breakaway anyways i'm gonna continue to test with different setting but maybe you guys can help me 


Thank you for your helps 


  • Link to post
    Share on other sites

    Posted · overextrusion using 2 extruders (pla with pva)
    7 hours ago, b16ior said:

    when changing again from pva to pla it puts too much materials


    The prime tower is meant to deal with any flow inaccuracies, so that anything is nice and equalized when the extruder comes back to the actual object.


    My advice is: if it really needs to be printed in this orientation - enable the prime tower (or use a bigger one). Place it near the printed object.


    Although - the part looks like it could be printed upright  - and without support structures. Would this be an option?


    BTW: which nozzle size is this printed with? 0.25mm?

  • Link to post
    Share on other sites

    Posted · overextrusion using 2 extruders (pla with pva)



    Sorry for the late answer i was really busy with exams this weeks and thanks a lot for your advices !


    I've tried with the prime tower and it was exellent. I'm printing with a 0.4 AA i'm not sure i have a 0.25 available at my lab but will definitely ask. 


    I didn't know you could place the prime tower near the printed object so i will try to cut some print time maybe ? 


    I've noticed that i'm almost hitting the object when the nuzzle is going to the prime tower so i thought about checking the z-hope when retracted parameter or the z hope after extruder switch. 


    Your idea of printing the model downward could be very nice the tricks is that my part is similar to a plate so what coold be the best for printing a plate upward or downward ? 


    Thank you again for your concerns 




    PS: i'm gonna post photos of my project so you guys can follow my advancement 


  • Link to post
    Share on other sites

    Posted · overextrusion using 2 extruders (pla with pva)

    1) Please post your project file (which will include the model).  Or at least post the model.  I don't understand the shape.  Is it supposed to be spherically curved?   (in cura "file" "save project as").


    2) Putting the tower closer to the part doesn't just save time.  During that travel time the nozzle can leak.  The shorter the travel, the better.


  • 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

      • Here it is. The new UltiMaker S7
        The UltiMaker S7 is built on the success of the UltiMaker S5 and its design decisions were heavily based on feedback from customers.
        So what’s new?
        The obvious change is the S7’s height. It now includes an integrated Air Manager. This filters the exhaust air of every print and also improves build temperature stability. To further enclose the build chamber the S7 only has one magnetically latched door.
        The build stack has also been completely redesigned. A PEI-coated flexible steel build plate makes a big difference to productivity. Not only do you not need tools to pop a printed part off. But we also don’t recommend using or adhesion structures for UltiMaker materials (except PC, because...it’s PC). Along with that, 4 pins and 25 magnets make it easy to replace the flex plate perfectly – even with one hand.
        The re-engineered print head has an inductive sensor which reduces noise when probing the build plate. This effectively makes it much harder to not achieve a perfect first layer, improving overall print success. We also reversed the front fan direction (fewer plastic hairs, less maintenance), made the print core door magnets stronger, and add a sensor that helps avoid flooding.

        The UltiMaker S7 also includes quality of life improvements:
        Reliable bed tilt compensation (no more thumbscrews) 2.4 and 5 GHz Wi-Fi A 1080p camera (mounted higher for a better view) Compatibility with 280+ Marketplace materials Compatibility with S5 project files (no reslicing needed) And a whole lot more  
        Curious to see the S7 in action?
        We’re hosting a free tech demo on February 7.
        It will be live and you can ask any questions to our CTO, Miguel Calvo.
        Register here for the Webinar
          • Like
        • 13 replies
      • UltiMaker Cura 5.3.0-Alpha 🎄 Tree Support Spotlight 🎄
        Are you a fan of tree support, but dislike the removal process and the amount of filament it uses? Then we would like to invite you to try this special release of UltiMaker Cura. Brought to you by our special community contributor @thomasrahm
        We generated a special version of Cura 5.2 called 5.3.0 Alpha + Xmas. The only changes we introduced compared to UltiMaker Cura 5.2.1 are those which are needed for the new supports. So keep in mind, this is not a sneak peek for Cura 5.3 (there are some really cool new features coming up) but a spotlight release highlighting this new version of tree supports.  
          • Like
        • 17 replies
      • New here? Get ahead with a free onboarding course
        Often getting started is the most difficult part of any process. A good start sets you up for success and saves you time and energy that could be spent elsewhere. That is why we have a onboarding course ready for
        Ultimaker S5 Pro Bundle, Ultimaker S5, Ultimaker S3 Ultimaker 2+ Connect.   
        They're ready for you on the Ultimaker Academy platform. All you need to do to gain access is to register your product to gain free access. 
        Ready? Register your product here in just 60 seconds.
          • Like
        • 14 replies
    • Create New...