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CURA slicer, gaps between inner walls and infill


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Posted · CURA slicer, gaps between inner walls and infill

Please can someone advise as to slicer setings to change to correct my problem, details given below. I have already tried tweaking as many things as possible and all to no avail.


I have tried varying wall counts, vastly increasing the overlap setting and different patterns of infill and top/bottom layers, nothing has helped. I have tried enabling extra blobs to fill gaps, and disabling it, and toggling the "filter out tiny gaps" option. I have edited each of wall thickness and line count and even tried adjusting wall line widths in the quality settings. If this is a printer isue rather than a slicer issue, then please advsie what settings to try in the slicer so as to properly be able to diagnsoe what is wrong with the printer.


Problem description:


I have a Creality CR20 pro

I am using the Cura slicer, version -4.11.0 (linux ubuntu)

It seems that the inner walls, such as on the central shaft of this gear test piece, are underextruded and leave gaps between them and the main infill, as well as between them and the top/bottom layers of the part.

I've tried prints adjusting about every setting related to wall thickness and top and bottom layer counts, and still keep getting these gaps beside the walls. Yet in cura's preview view nothing looks wrong for any of the options tested.

2 images are attached, two showing the gaps visible from the top side. Holding the printed items up to light shwos many of these gaps run right through to the bottom. Pausing a print halfway through to take a good look also showed that these gaps beside the inner wall are present in layers at infill heights as well as in top and bottom layers.


My slicer settings are:

The standard cura print profile as shown in image, I couldn't see a quick way to export them as text from cura so took screenshots. This shwos one of the many different combinations for wall thickness, top/bottom layers, top/bottom patterns, infill density and pattern, and support wall line count and infill overlap percentage which i tried. All still have the same issue on multiple different printed objects. Bed is 65C, nozzle is 200C, filament is grey PLA (eryone), print speed and nozzle retraction are at the default values for the CR20 pro, which I think are the same as for the standard Ender 3 profile, but I'm not quite sure how to look those settings up. However I have slowed the speed during the raft phase due to trouble in the past I had with rafts warping up from the bed, this fixed it so I kept low speed for the raft.


Thank you for your help




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    Posted · CURA slicer, gaps between inner walls and infill

    Zooming in on the photo of the 4 gears they are 15 to 20% under-extruded.  Before you start changing other settings I think you need to address that.  The center walls of the hole for the shaft look more like hex's than circles.  I think that's because the plastic wasn't getting smashed down and instead it was dragging in towards the centerline of the hole.

    This is your photo.  I've added some red lines where there is under-extrusion.  Fixing it might be as simple as calibrating the E-steps.  It could be other things as well but that's where I'd start.


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