Jump to content
UltiMaker Community of 3D Printing Experts

Lower layers are bumpy and rough

Recommended Posts

Posted · Lower layers are bumpy and rough


I can upload a photo if needs be but it's simple to explain. After the brim is printed and the model layers start, the first few layers are bumpy and messy, and then it slowly starts to get better. Any thoughts?



  • Link to post
    Share on other sites

    Posted · Lower layers are bumpy and rough

    Could be a couple of things:

    - Your bed is a bit too close to the nozzle. During the brim pressure is building up but not escaping, when it's doing the first layer pressure is building up as well but eventually it manages to break through and a blob of plastic is the result. Does it look like there's a really really thin layer of plastic for a while and then suddenly it gets bumpy - rinse repeat?

    - Your filament may be thicker than the default 2.85mm that is set in the firmware. Measure your filament diameter in several places. Also measure at 90 degree angles in case it is oval. See if it's significantly higher than 2.85mm. If so, change that in the material settings on the printer.

    - Could also be that the plastic isn't adhering well to the bed. If you're printing without glue, make sure the bed is very clean, fingerprints will stop the plastic from sticking. If you're using glue, make sure it's a nice and thin layer. Put on a thin layer of glue and then use a wet piece of cloth to spread it around and then let it dry. You'll barely be able to see the glue.


  • Link to post
    Share on other sites

    Posted · Lower layers are bumpy and rough

    I'll give all that a try, thanks.

    Checking the filament I get 2.86 - 2.95 at various points. It's an ellipse though in cross section, so not a 2.95 diameter circle.

    I do use glue, it's very thin. So I'll re-level the bed. When it says to move the bed closer to the nozzle until you feel th paper catch a bit, how much should it catch? I can just about feel it catching.

    When this print finishes I'll upload some close up shots so you can se the brim. If I can get it off the bed, these things stick really well.


  • Link to post
    Share on other sites

    Posted · Lower layers are bumpy and rough

    Really "bumpy" can describe at least 3 different problems so a picture would be best. It's likely either too close or too far levelling issue.


    I can just about feel it catching.


    Perfect. Levelling is very critical but once you get it you shouldn't have to touch it for weeks.

    If you are too close then the extruder buildes up pressure and the feeder skips and you get under (no) extrusion for a few seconds and that looks kind of bumpy. If you are too far the lines that you lay down initially are wavy and not properly squared off and it looks like the printer is drunk. And it doesn't stick well.

    And there are other possible issues.


  • Link to post
    Share on other sites

    Posted · Lower layers are bumpy and rough

    During direct printing on glass without adhesive help you see it more clearly. If you have leveled very close to the glass, then the first layers, look almost like a cloudy sky. Particularly clear you can see it if you use colored material with transparency. I think it also has to do with the fact that a glass surface is never totally flat. So you can see the topography of the glass. Or is that wrong?


  • Link to post
    Share on other sites

    Posted · Lower layers are bumpy and rough

    I think my levelling is good then, as I'm getting squashed but clearly defined layers. I'll see war happens today, latest print has been running for 12 hours and has another 8 to go. Although that time is changing regularly.


  • Link to post
    Share on other sites

    Posted · Lower layers are bumpy and rough

    the first few layers are bumpy and messy,


    Your starting to annoy me that you still can't post a picture. It just occurred to me maybe you meant the *sides* of the layers and not the bottom surface. That is usually caused by build plate too hot - 75C is too hot. 70C is okay. 60C probably better depending.


    • Like 1
    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
        • 12 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...