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Print Inconsistencies Between R2's and Relative to Z-Height

Discussion in 'Troubleshooting' started by RoboticsRob, Aug 30, 2020.

  1. RoboticsRob

    RoboticsRob Member

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    Hi everyone. I've got a few R2's, and the print quality varies wildly between them. Here's an example of a part printed on two of my R2's, same gcode, printed simultaneously, printers in the same room, same filament brand, and both printers do have a z-stepper support installed.

    Note that the printer that printed the white z-stepper support tower shows no real issues when printing parts that are under 15mm in height, so it seems this is likely more hardware related than anything.

    What may cause the R2 to display reduced print quality like this as the z-height increases?

    Thanks everyone. Also soliciting feedback on suggestions to better hide the z-seam, as I've not entirely ruled that out as a contributing factor.
     

    Attached Files:

  2. mark tomlinson

    mark tomlinson ༼ つ ◕_ ◕ ༽つ
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    In your slicer turn on the randomize layer start position if you have not already (this will impact the seam)
    As for the defects as it move up that sound like a loose gantry issue. As the height increases the amount of play is likely increasing and that is what is getting you. Sanity check the gantry is square and tight.

    The gantry alignment procedure is here: https://help.robo3d.com/hc/en-us/articles/115001792512-Gantry-alignment
    the tool is here (assuming you don't still have the ones that came with the printer): https://www.thingiverse.com/thing:2532723
     
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  3. RoboticsRob

    RoboticsRob Member

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    Hey Mark, thanks for the ideas. I did do a gantry alignment following that procedure (I will go re-do the procedure to double check, since you think it could be at fault)... Ok I went and double checked and the belt tension is nice and uniform all around, but sure enough, I just noticed that the timing belt pulley you loosen when adjusting the gantry belt tension is doing double duty and also controlling the positioning of the gantry within the printer and sure enough, one of the rods has about 1.5mm or so of play back and forth..... so I will go re-adjust that paying attention to not only the belt tension, but the gantry retention/position. I love adjustments that simultaneously adjust more than 1 variable....

    As for the slicing settings, I actually quite like the z-seam being lined up, because you can put it in the back or place it where you'd like for any parts that it matters on. I should have noted, these are PETG with a 0.6mm plated copper nozzle, and I almost exclusively print PETG and TPU, so using the random layer starting point incurs random little blobs/zits all over the exterior of the part (suggestions to minimize that little blob further are also appreciated, though admittedly I've not run anything with random z-seam since doing a bit of further profile tuning, so maybe thats overdue to retest also).

    Thanks Mark, I'll go double check all my gantries again and rerun a set of test prints to look for any improvements.
     
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  4. tkoco

    tkoco - -.- --- -.-. ---
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    Double check the temperature settings for the filaments. Different colored filaments along with different manufacturers of filament could have different temperature ranges similar to PLA filaments. It's one of the factors which need to be checked before slicing the model.
     

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