Jump to content
UltiMaker Community of 3D Printing Experts

Feature Request: multi-extruder, single nozzle, without prime tower


Recommended Posts

Posted · Feature Request: multi-extruder, single nozzle, without prime tower

The motivating problem: I have recently experienced frustrating print failure at near-completion of a large, tall 2-color PLA print on a Creality CR-X (2 extruders, 1 hotend)—the problem is that even with a large prime tower footprint, when it gets tall (200-300mm), the torque from the printing pries the prime tower loose while adding layers.  Also, it is extremely wasteful of material.  


The solution (a new feature): It occurred to me that the prime tower would be completely unnecessary if the G-code would instruct the machine to perform filament switch before finishing one color so as to push the leftovers out on that same color, and then prime the next color into the interior of the part, for example fill or inner walls.  In this way, the primings are integral to the object being printed, resulting in zero waste and more robust printing.  This feature could be implemented in Cura with perhaps a checkbox and 2 parameters (the length to continue extruding after filament change and the volume to prime, which is already a parameter) and some programming to sequence the operations near a filament change.  There may also be the need for a feature that warns the user if there is not enough infill or inner wall to handle the desired priming volume.


Best Regards and thanks for the sweet software!


  • Link to post
    Share on other sites

    Posted · Feature Request: multi-extruder, single nozzle, without prime tower

    That's interesting but you run the risk of the part being knocked over when the priming is done on the inside and the printhead is wiped against the inner walls. Or to have small bits of filament sticking out of your part and messing up the layers and the coloring, in case the priming isn't perfect and tehre's still some leakage.


    It's been suggested to UM to make the prime tower conical: wider at the base and thinner at the top, to give it even more stability with the round shape, I do not know if this is on their todolist and would be implemented in Cura 4.0 or later, or maybe it is on list of things that would be nice to code but are not considered that important.



  • Link to post
    Share on other sites

    Posted · Feature Request: multi-extruder, single nozzle, without prime tower

    Thank you, Brulty.  I appreciate your points on that.  I have found that this issue of oozing can be easily addressed as follows.  At extruder switch, active extruder is retracted 100 mm by setting position to -100.  Then tool is switched to next extruder and instead of setting position back to 0 (thus reversing the complete 100mm retraction), the position can be set to -5 so that there is no oozing.  Then the risk is only of missing a small bit of material on the infill, which I do not forsee to be a problem.  The machine already retracts and de-retracts many times during a print.  An extruder switch would be no different.  Of course, this would not be universally applicable to every conceivable print, but gosh would it save a lot of waste material from the environment and save a lot of headache with failed prints.  In my case, the print has a wide base, so it is not nearly as susceptible to knocking over as the prime tower.  Another benefit would be that build space would not be taken up by the prime tower.

  • Link to post
    Share on other sites

    Posted · Feature Request: multi-extruder, single nozzle, without prime tower

    In my experience, using a UM printer with UM-brand filament, prime tower have become useless. I guess it should be possible to find settings with any combination of printer and filament to make the prime tower useless as well, thus saving a lot of time and material.

  • 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
        • 7 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
        • 16 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...