Vertical Banding?

[Alishkus]

Hello,

I went into problem where I have tried almost everything and I am not sure what problem I am facing - mechanical or software?
Bellow you can see the prints with two identical printers.
Both printers has same* setup and same electronics (duetwifi).
However in one printer I have near perfect prints and other has huge problem with vertical banding. It looks like that it tries to repeat every mesh segment with stopping in every corner....


Anyone had similiar problems before? Extruder? Software? Drivers?

[DocTrucker]

Looks more like ghosting / ringing from the pictures? The first print has hardly any sharp corners and the second is full of them?

[DocTrucker]

Having said that the rining on the log appears to not die down as you would ecpect from ghosting. Are you axis belt driven? Does the pattern pitchatch the belt pitch?

[Alishkus]

Its not ringing. For ringing test I print XYZ cube at 70-90mm/s and very little ringing appears.
and this is test print in vase mode from today...

And yes axis are belt driven and vibration.banding pattern looks almost the same as belt pattern

[DocTrucker]

The pattern doesn't look like it's repeating the triangular mesh pattern from an STL. Have you looked at the STL to see if it is close? Are you running the toothed side of the belt over smooth idlers? Reasonably consistant belt tension between the two machines?

[Alishkus]

Its hard to say on rounded surface for triangular mesh, but on straight line (like OWL log) its not repeating any triangular mesh.
I am runnign toothed belt side on smooth idler (Y axis) and X axis is driven by 2 motors and they are also connected mechanically.
Belt tension is OK

[Alishkus]

[dc42]

It could also be an extruder problem. Try changing the layer height, and see whether the spacing of the banding changes (indicating an extruder problem) or remains constant (indicating an axis problem).

[Alishkus]

I have printed this one in 0.2 layer and banding is very very small but still exists. And layer consistensy is shit Maybe its really extruder, but from the side all looks smooth.
I

[dc42]

@alishkus said in Vertical Banding?:

I have printed this one in 0.2 layer and banding is very very small but still exists.

What layer height did you use before?

[Phaedrux]

Can you post your config.g and slicer settings? Some of it looks like ghosting.

Has this always been the case, or has it developed over time? Something could have become worn, or loosened over time. Bearings could start running rough.

[Veti]

have you checked each bearing separately? could be some debris in there

[Alishkus]

@dc42 for this particular print it was 0.2mm layer with 0.6 head
Ussualy with 0.6nozzle im printing 0.3-0.4 layer

@Phaedrux looks like this is developing over time and getting worst and worst

I already have inspected bearings and they all are perfectly smooth.
I have few more ideas where I will work on Monday (maybe Sunday).

Problem is that I saw what this build is cabaple of and now I cant repeat it

[Alishkus]

Ok. That escalated quickly.
Instead of 500 I wrote 50 in Jerk.
Is there any guide how to calibrate printers Jerk vs accelaration so to have less resonance as possible.

[Phaedrux]

@alishkus Can you post the STL? It looks like it may be fairly low polycount with large deviations at the facets.

As a test could you try printing this STL?
0_1543253139548_elephant-statue-1.stl

This file seems to be low resolution enough that it will produce similar results for me. The chunkines in the XY plane also occurs in the XZ and YZ planes which seems to result in bulges at the corners as well as what appears to be Z banding.

I had better results with higher jerk and higher acceleration and lower layer height, but there was really only so much that could be done.

[Alishkus]

@phaedrux I am still testing Jerk/Accelaration settings. But for now output is pretty good I think 0.6nozzle 0.3 layer devil design PETG

[Phaedrux]

@alishkus Yes that's much better than my early results. I gave them away as toys, so I can't show what they looked like, but it was similar to the photos you posted with the ridges.

What acceleration, jerk, speed settings were you using on that print?

[Alishkus]

@phaedrux lower your accelaration, increase Jerk.
Make sure all belts and at right tension