Jump to content
UltiMaker Community of 3D Printing Experts

PLA shrinking


jcosmo
 Share

Recommended Posts

Posted · PLA shrinking

Ive been doing calibration on my printer and finding that I seem to be getting shrinkage in the x and y directions.

Its very uniform, such that the 20mm boxes come out at 19mm quite consistently. At first I thought it might be slipping somewhere in the drive mechanisms, but I noticed that whe I printed a hollow box that the base is accurately 20mm square, and the. The layers above "step in" to 19mm square. The box itself is very consistent above that point, indicating to me that the accuracy of the printer probably isn't the problem.

Any hints?

Does PLa shrink in this fashion? I'd read ABS was more prone to shrinking than PLA.

Is it likely that the is a mechanical problem somewhere in the printer instead?

Rather rushed photo

  • Link to post
    Share on other sites

    Posted · PLA shrinking

    A better photo:

    http://www.flickr.com/photos/jasoncosmo ... otostream/

    I attached the gcode file & cura profile.

    Interestingly I just ran off four of Daid's UM feet and whilst they don't exhibit the 'elephant foot', they are all 29x29x20 rather than 30x30x20.

    http://www.flickr.com/photos/jasoncosmo ... otostream/

     

  • Link to post
    Share on other sites

    Posted · PLA shrinking

    Observing the print process as closely as possible I think that the printing is being done at the 19mm box size, but that the foot was printed larger, so probably not a shrinking problem but a problem in the size it's attempting to print to.

  • Link to post
    Share on other sites

    Posted · PLA shrinking
    Observing the print process as closely as possible I think that the printing is being done at the 19mm box size, but that the foot was printed larger, so probably not a shrinking problem but a problem in the size it's attempting to print to.

    Hi

    I couldn't see anything wrong in the GCode

    Things to check

    Steps per unit for x and Y. Default is 78.74

    Do a 100mm X 100mm square to see if the error is proportional, that is about 3% out (should be 3mm out), or if it is still out by 1mm

    Let us know how you go

  • Link to post
    Share on other sites

    Posted · PLA shrinking

    FYI,

    I've printed a "tube" of 118 mm inner diameter (should fit OVER something that we measured as), and it came out 116. About 2% error.

    Then I printed an L shape with 100 mm between the surfaces (on the same side). That measured up as 99.8. only 0.2% error. It might be that it's overflowing my edges.

    The L-shape comes out bent: The PLA shrinks a bit.

  • Link to post
    Share on other sites

    Posted · PLA shrinking

    I've had to take the hot end apart and remove plug - first time I've had to do that so took a while.

    The X & Y steps per unit are as described.

    I'll go over the machine and check all the belts and pulleys, install the belt tensioners I printed a while back, and then see how it comes out.

  • Link to post
    Share on other sites

    Posted · PLA shrinking
    Interestingly I just ran off four of Daid's UM feet and whilst they don't exhibit the 'elephant foot', they are all 29x29x20 rather than 30x30x20.

    http://www.flickr.com/photos/jasoncosmo ... otostream/

     

    The tipped corners are rounded off. Mine are also 29x29mm.
  • 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
     Share

    • 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
        • 9 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
        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
        • 14 replies
    ×
    ×
    • Create New...