Jump to content
UltiMaker Community of 3D Printing Experts

Print is not straight


Recommended Posts

Posted · Print is not straight



Last week I assembled my Ultimaker but found my print is not straight, I have tried some of solutions here but still have no luck to have the problem fixed.


This problem makes me unable to print anything with my new Ultimaker :sad:

Print is not straight. Z Axis Issue?

I have already spent the whole weekend on figuring out the potential root cause:

1. Added 4 washers under X motor to avoid friction between belt and wood

2. Ran bed level wizard for many times

3. Rebalance the X motor pulleys


Two things I suspect are the Z axis rod is wobbling while bed is moving, also the drive nuts on the rod is not steady.


I have tried using glue gun to fix the drive nuts to tighten the rod and 2 axes, unfortunately, wobbling is still there and print is still bad... Is there any idea how to solve the issue?


Could you please advice me what else I can try?


Thanks a bunch!


  • Link to post
    Share on other sites

    Posted · Print is not straight

    If you've already checked that the belts aren't rubbing, then the most likely cause is that one of the X-Pulleys is loose.

    Check that they are all properly tight, including the one on the motor shaft itself. I gather that UM now includes replacement grub screw for the pulleys, in case the ones included in the pulleys by default don't fix tightly enough.

    I would try making a mark on each pulley and the shaft it is attached to with a sharpie, so you can see if there is any movement during the print. And I'd definitely avoid glue. Not sure how well that's going to attach anyway, but I think it's going ot cause more problems than it solves.


  • Link to post
    Share on other sites

    Posted · Print is not straight

    This problem you post about is very common and usually easy to fix. There are many causes. After seeing your picture it is almost certainly one of two problems: A) setscrews or B) rubbing belt.

    You already addressed B but did you make sure the belt isn't twisting each time the X motor changes direction? It's the motor behind the robot in this picture (back right corner). Not only might you need to add the washers (which you did) but you might also have to slide the pulley closer to the motor. It should be as close as possible without touching the motor - mine are about .5mm from the motor.

    But more often the problem is that the set screws aren't tight enough (as illuminarti says). You should do at least 2 of the following things:

    1) tighten the hell out of all 6 screws (six! not 4, not 5, but six). Tighten it until you are almost to the point where you are afraid you will break something. The most common problem screws are the two pulleys on the short belt because the other 4 pulleys have half as much load (but they can slip also so tighten all 6).

    2) Mark the pulleys: Use a sharpie (aka permanent marker). Put a tiny mark on each pulley and on each rod. Perhaps even photograph them or make a note of how perfect your marks line up. After printing another part that slides, recheck the markings.

    3) Replace the existing setscrews with the extra ones. The extra ones are supposedly better (pointier, sharper) but I haven't used mine yet as the ones that came inside the pulleys are working fine for me.


  • Link to post
    Share on other sites

    Posted · Print is not straight

    Thanks very much GR5 and illuminarti for so detailed and prompt reply!

    You guy are genius! :-P After tightening all setscrews on rods, the print is close to perfection! I spent too much time on fixing the z rod, which is definitely in a wrong direction. Your solution really saved me lots of time!

    There is still a small defects on my print, as you can see from the picture below, the top of the robot's head is a little bit melted by hot end when print ended, can I avoid this by tuning up the Cura settings or Ultimakers?

    Thanks again!

    Issue resolved after tightening all setscrews on rods


  • Link to post
    Share on other sites

    Posted · Print is not straight

    This is a common problem with the UM robot. Because the antennae are so quick to print they don't have enough time to cool and they slump.

    There are two parameters (maybe only one) you need to adjust to fix this:

    1) Under Advanced, "cool" section make sure minimum layer time is at least 5 - 7 seconds is default (if fan is off then double these values).

    The second parameter - probably the one causing your problem is

    2) Under "expert settings", "cool" section set minimum speed to zero. Not only is there a bug in this setting for some versions of Cura, you probably don't need it with the newer ultimaker hot end design.


  • Link to post
    Share on other sites

    Posted · Print is not straight

    Thanks a lot, gr5!

    I tried one more time, when Cura was printing robot's antenna, the hot end was swamped by printing materials. Actually I tried gr5's suggestions, but looks like it might help some old versions of Cura, the melting problem is still there after applying the suggested settings.

    I think the melted robot's antenna might be caused by the layer settings.

    I am using the latest Cura 13.06.05, for some reason, the layer height is changed to 0.1mm in this version. I checked the settings in Cura 13.04, the default layer height is 0.2mm.

    Once I changed the layer height back to 0.2mm in Cura 13.06.05, the melting problem is gone, however, which is expected, the print quality is worse.

    I tried to use Flowthermostat Cura plugin, but looks like it is incompatible with the latest Cura, and temperature is always constant.

    Any ideas to print the tapering top such as robot's antenna without losing quality? (layer height: 0.1mm)

    Thanks in advance!


  • Link to post
    Share on other sites

    Posted · Print is not straight

    You should start a new thread.

    What temp are you printing at?

    I'm not sure if there *is* a fix. Those antennas are tiny and even though you print only one layer every 7 seconds, the head is still touching the antennas most of the time.

    There is some new kind of head-cool-retraction setting in the new cura. I'm not sure what it does but I think it is supposed to rest above the part for 5 seconds to let the layer cool.

    I guess I would manually lower the temp when the printer is almost done with the robot's head. I would lower to 185C and then when that is stable for a few minutes I would lower to 180 (if you hit 170 I believe Marlin shuts off the extruder so be careful). I would experiment with printing only the top of the head of the UM robot.

    Another solution is to create a "cooling tower" where you print a small pillar next to the robot while printing the robot at the same time. The problem is then you will have stringing issues which have their own challenges (but can be dealt with nicely after some experimentation).


  • 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

      • UltiMaker Cura 5.3 stable released
        In this stable release, Cura 5.3 achieves yet another huge leap forward in 3D printing thanks to material interlocking! As well as introducing an expanded recommended print settings menu and lots of print quality improvements. Not to mention, a whole bunch of new printer profiles for non-UltiMaker printers!
          • Thanks
          • Like
        • 21 replies
      • 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
        • 18 replies
      • UltiMaker Cura 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
        • 22 replies
    • Create New...