Geeetech

On the A20m I got non planar wall, look like mini stairs (see pictures), specialy on cube border along z axis, this is a very small default but I have not this problem with my other printer.

Those mini stairs are constant along z axis on the whole height.

Any idea ?

the right side of X axis is too tight. And left side at Z screw possibly not tighten well.

Top side seems over extruded

thanks, so I should try to lose a little right X axis wheels ? I start a new print with this modification to see if it help.

The top layer is fine, probably the photo give this impression of over extrusion but it's really nice in reality.

I tight the left x axis wheel and lose the right one but unfortunatly no change , result is the same, little stairs are still there, do you think I should try to tight it even more ? NB: they appear in all the fourth borders along z axis.

I noticed that the default A20m profile on Simplify3D set the jerk to 10, I will try with 9 and see if it help.

same result with a jerk set to 9 ...

both GT2 and bed wheels are tight?

Yes they seems to be ok, but I will tigh them a bit more and check if that help.

Also I am wondering if it is not related to retractation because stair seems to be 4 layer height and retractation occur on each corner every 4 layers (according to simplify 3d preview), first layer it retract on border 1, 2nd layer it retract on border 2 etc...

Also in vase mode the stairs completly disapear.

Some more tests results :
- Trying with the second extruder (a20m) and a different filament doesn't help, same issue.
- Disabling retractation doesn't help

It is maybe something related to slicing (Simplify3D) because I notice that the nozzle go twice at the same location exacly every 4 layers, and stair's are every 4 layers.

I mean there is maybe something wrong on the slicing, because it go on the outer perimeter, draw it, than get back at the same location it started rather than a bit before, so the nozzle print twice at the location it started the outer perimeter.

Hi, you can check if your institution is loose,
If it is, tighten it.
Try to re-slice the model.

could be related to the lack of newer features like junction deviation & linear advance being available to use.

Yes maybe, I read a lot about linear advance and my conclusion is that it has also probably a downside, because if not I suppose that all manufacturer will enable it with a default value that works in most case , but maybe they already do that ?

I dont read and dont know a lot on junction deviation but I see that it has something to do with corners, but on this cube corners are nearly perfect with no infill even with multiple outline, I am not sure it will help in this special case.

I really think that this problem may come from the path of the nozzle when using infill. I will investigate more on the generated gcode to see if I am right or wrong. Maybe I missed an option in the slicer but I have done so many tests.

For now here are some results :
Those tests have been performed on two printers a20m, cr10s pro, three differents extruders, three différents filaments, two nozzles 0.4 and 0.6, one slicer Simplify3d.
Layers height : 0.3
Vase mode => render is ok
Two outline + infill 15% overlap infill 15% => render stairs on corner
Two outline + infill 15% overlap infill 0% => render stairs on corner
Two outline + infill 3% overlap infill 15% => render stairs on corner
Two outline + infill 1% overlap infill 15% => RENDER IS ok ! ( I really cant explain this result )
One outline no infill => render is ok
Two outline no infill => render is ok
N outline no infill => render is ok

NB: with layer of 0.1mm all print are ok, with or without infill, at least my vision is not enought accurate to see them...

It is a very small defect, less than half a millimeter, that appear with layers of 0.3mm height, nearly invisible with lower layers height.