Jump to content
Ultimaker Community of 3D Printing Experts

Consistently clogging in the Bowden tube


Recommended Posts

Posted · Consistently clogging in the Bowden tube

I have a Creality CR-10 Mini, and I've had a constant problem of filament clogging in the Bowden tube. I've gotten through entire spools with no problem, but then sometimes it'll print for an hour when a clog occurs. The stepper gear will start slipping since it can't push any filament in, and if I try to manually push/pull the filament, it goes nowhere.

 

I've ran filament at various temperatures, I've used different brands of filament, I've used different Bowden tubes. I check the level of the bed before each print, and when I connect the Bowden tube, I keep the nozzle unscrewed about 1-2 turns, push it as far as I can, and then screw in the nozzle. I'm also very careful to square the tubing before putting it in. I've cleaned the stepper gear with a toothbrush and alcohol, too.

 

I don't know what the cause is, and I don't know what to do. I'm running on fumes trying to figure it out, and any help would be appreciated.

  • Link to post
    Share on other sites
    Posted · Consistently clogging in the Bowden tube
    15 hours ago, dadinfinitum said:

    ...and when I connect the Bowden tube, I keep the nozzle unscrewed about 1-2 turns, push it as far as I can, and then screw in the nozzle.

    I think that's too far.  Try 1/4 - 1/2 turn instead.  With 1-2mm of the Bowden tube sticking out and getting squished when you tighten the nozzle, the inside diameter of the bowden tube will get squished smaller.  Prints with a lot of long retractions will move soft material into that necked down area and cause a blockage.  Prints without a lot of retractions don't seem to notice near as much.

  • Link to post
    Share on other sites
    Posted · Consistently clogging in the Bowden tube
    43 minutes ago, GregValiant said:

    I think that's too far.  Try 1/4 - 1/2 turn instead.  With 1-2mm of the Bowden tube sticking out and getting squished when you tighten the nozzle, the inside diameter of the bowden tube will get squished smaller.  Prints with a lot of long retractions will move soft material into that necked down area and cause a blockage.  Prints without a lot of retractions don't seem to notice near as much.

     

    Thanks for the insight. I've also been told to check my fan settings. Here's hoping it works.

  • Link to post
    Share on other sites
    Posted · Consistently clogging in the Bowden tube

    The hot end fan runs 100% and continuously so there aren't any settings for that one.  The layer cooling blower is adjustable and if you have a beastly blower installed and it blows on the nozzle too much it can cause hot end problems.  The stock one shouldn't be causing issues.

  • Link to post
    Share on other sites
    Posted · Consistently clogging in the Bowden tube

    Have you checked to see if the main hot-end cooling fan is working while you are printing?

     

    I've been have the same type of issue with my CR-10. I started to get heat creeping up the Bowden tube and clogging it. I've tried a few different things and tests some small prints and found the the hot-end cooling fan is not turning on during print.

    I have tested the unit and when I do a normal preheat the fan is on a t all time. once I try to start a print the fan turns off. I've tried to turn on all the fans manually in Cura to no success. I've been using Cura for a couple years now and just started having this issue in the last couple months.

    So far I've had to replace my hot end because the original one got so badly clogged with plastic I couldn't fix it. I done' know how many nozzles I have clogged and Bowden tube I have gone through.

    Going to be running a new test and turn the fan on manually to see if that work. I'll keep you informed

    I'm running a Creality CR-10 V1 and using Cura 4.8

  • Link to post
    Share on other sites
    Posted · Consistently clogging in the Bowden tube

    The hot end fan is hard wired in the "On" position.  When the printer is on, the fan is on.  There are no controls for it, there are no Gcode commands you can send that will effect the RPM, or turn it off or on.

    If it's turning off by itself I think you may have a problem at the mainboard and it might be as simple as tightening the screws that bind the wires for the hot end fan.  Check for any chafing along the length of the hot end fan wires as well.

     

    I was never able to overcome the heat creep with the stock hot end.  Eventually I stripped the threads for the nozzle on about the 500th time I pulled it out to clean it.  Although a heli-coil insert worked as a repair, I bought another stock hot end.  Same problems.  Now it's a Micro Swiss.  Not perfect, but a lot better.

     

    One of the problems I had with my Ender (same print carriage and hot end assembly) was the mainboard fan.  It IS wired to turn on and off with the layer cooling blower (not variable speed, just on-off).  I printed a lot of PETG with the cooling blower turned off to avoid warpage, the mainboard fan didn't turn on, and eventually the mainboard components would overheat.  The fix for that was to wire the mainboard fan to the terminals of the hot end fan - because it's always on.

     

    Eventually I designed a deflector that fits inside the hot end housing and directs the flow from the hot end fan at the heat exchanger.  That wasn't enough.  With a 3mm shim behind the hot end housing mounting surface, a 4015 ball bearing fan will fit into the housing.

  • 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

      • Startups, apply for the Forward AM Innovation Award!
        Are you a startup using 3D printing? Perhaps you should continue reading... 
         
        Together with BASF we are launching the Forward AM Innovation Award - the very first global contest for startups developing new applications with 3D printing!
         
        Why apply?
        The winning startup will receive €100,000 in goods and services*, along with coaching and marketing exposure from top-notch leaders in the industry.
         

         
        Who can apply?
        Your startup creates products using Additive Manufacturing, is less than 5 years old, and has less than 50 employees. We are looking for 3D printing applications with a strong focus on innovation, sustainability and scalability.
         
        Dental aligners, shoes, tools, automotive parts, music instruments, industrial tooling and molding, medical implants, sports equipment, toys, architecture, fashion, construction... all are welcome to join!
         
        Do you have an innovative, sustainable and scalable idea that leverages the unique possibilities of 3D printing? Then it is time to apply!
        More information can be found here.
         
        Applications close on March 28th, 2021
        * What does "in goods and services" mean?
        The winner will be able to pick any item from the overall product and service portfolio of the sponsors, e.g. printers, materials, consulting, software... Choose whatever you need to accelerate your startup.
         
          • Like
        • 0 replies
      • New here? Register your Ultimaker for free 3D printer onboarding course
        Hi,
         
        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
        • 0 replies
    ×
    ×
    • Create New...