Jump to content
UltiMaker Community of 3D Printing Experts

Gaps in z-seam when printing stringing test tower

Recommended Posts

Posted · Gaps in z-seam when printing stringing test tower



I'm busy this week setting up my printer after adding a second Z-spindle to my Ender 3Pro.


I modelled a stringing test tower and printed it a couple of times with no infill, no top layers and a single wall.

When putting the z-seam in the back (this is the front of the tower in the picture) I noticed one tower has gaps in z-seam.






I tried to solve this by lowering the print speed from 50mm/s to 40mm/s, increasing flow to 105% and 110%, z-hop on/off, prime from 0 to 1mm^3.

There seemed to be some improvement but no solution.

(The warping in the left bottom was caused by me pulling the print of the still hot bed as warping is, at this time, no issue)


After studying the tool path in the Cura slicer I noticed the difference in build up of the layer between the towers.


In the good tower the print head leaves the freshly deposited layer tangentailly in the same direction as the print direction, in the bad tower the print head leaves the freshly deposited layer also tangentially but after reversing 180degrees. Apperantly this caused too less material being deposited at the z-seam.



- Good z-seam location is the start position of the layer

- 1 is the tool head position just after the start of the layer

- 2 is the tool head position just before the end of the layer

- green arrow is the movement to the start of the next layer


The start of the red horizontal arrow to the left is the moment the tool head leaves the right tower.

The head of the red horizontal arrow is the start of the layer in the left tower.

The start of the green horizontal arrow is where the tool head reverses direction after the completion of the layer.


This issue doesn't occur, or isn't visible, when printing 2 perimeters.


Printing a single wall tower with random Z-seam location seems to solve the issue but the model looks very course then.


Is there a function in Cura or a WoW to solve this?


Material: PLA

Nozzle diameter: 0,4mm

Nozzle temp: 210degree centigrade

layer height: 0,2mm




  • Link to post
    Share on other sites

    Posted · Gaps in z-seam when printing stringing test tower



    Adding some travel from the bad z-seam location to, in this case, the left would solve it I think.

    I have no idea how to add this to the g-code, except by hand but in other models this migth be too difficult due to angles and a very large number of code lines.


  • Link to post
    Share on other sites

    Posted (edited) · Gaps in z-seam when printing stringing test tower

    Check your Outer Wall Wipe Distance (0.1 or 0.2 usually works OK) and make sure Coasting is turned off.  Retract at Layer Change and/or Retract Before Outer Wall may cause that as well.

    I haven't seen anything like that with my Ender 3 Pro and so I'm thinking it might be a setting.

    Edited by GregValiant
  • Link to post
    Share on other sites

    Posted · Gaps in z-seam when printing stringing test tower

    Thanks! :)


    Retract at layer change turned off solved the issue and now the printer produced a near perfect tower, very nice.


    (This is right after pulling it from the bed, no post-processing/rework whatsoever)


    This saved me a lot of money as I was about to order a Prusa mk3s+ in the hope to solve all issues.


    Thanks again.


  • Link to post
    Share on other sites

    Posted · Gaps in z-seam when printing stringing test tower

    Well, there ya go.

    I am not totally enamored with my E3Pro but after getting to know it and it's idiosyncrasies I've gotten it to work quite well.  The second part was Cura itself.  It is not a simple program to learn as there are a ton of options and some can interfere with others.

    Taking the time to calibrate everything from the frame geometry through the e-step calibration, the belts, the wheels, axis angles, etc. pays dividends in the end.  Knowing how to read gcode, how to look at a model and know what it needs to print well, how to apply all the Cura settings to get what you want out of the print...a lot of stuff goes into getting good prints out of any printer whether it's your Ender, a Prusa, an Ultimaker, or my own design the (yet-to-be-released) "Harry Potter 3d Platinum Pro XL Extended Cabriolet w/Easy Button".

  • Link to post
    Share on other sites

    Posted · Gaps in z-seam when printing stringing test tower



    Now I have printed a single wall "cube" and a CHEP-cube also.


    I'm so content with the current setup that I have ordered a second Ender 3Pro with all the updates I have on my first one plus a Micro Swiss full metal print head today. This will be my "hot printer" for PETG and LW-PLA to print parts for my RC planes.



  • Link to post
    Share on other sites

    Posted · Gaps in z-seam when printing stringing test tower

    As you learned from the first one - Assume that nothing is put together correctly from the factory and you will be good to go.

    The all-metal hot end is a good idea.  So is a more robust layer cooling fan.  The 4010 blower that comes stock is weak to say the least.  You don't need one of those gigantic dual blower monstrosities but a good ball bearing 5010 is much better than the stock blower.

    • 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

      • 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
        • 22 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...