Version 4.0 solves one problem, reveals another...

[Lorcoft]

I had been having an issue with thin walled prints, where the infill overlap was printing outside of the wall... resulting in a rough "cottage cheese" appearance...

Version 4 resolved this, with changes to the way it handles thin walls (kudos to the devs!!!).

The fix also revealed another issue...

I think this is an example of Y-ringing? The vertical line appears to be an indent on one side of the print and a protrusion on the opposite side. My guess is that I can fix it in the short term by making the wall slightly thicker, but I'd rather correct the problem.

If this is an example of y ringing, would adjusting the acceleration speed help?

thanks for any input & advice;

Lorcoft.

[arhi]

you have ringing on both those images, just different frequency, is the print speed same?

[Lorcoft]

yes, I didn't change the speed. I was working to fix the first problem with the infill overlapping the walls, and didn't want to complicate the issue by changing multiple settings at once so it's not surprising that there is ringing in both models; as the first problem I was having was hiding the 2nd...

If this is y-ringing, then I should start by changing the acceleration speed? I know that acceleration & jerk work together, but don't think I should be changing them both at the same time.

[arhi]

"ringing" on the first image is due to microstepping, ringing on lower image I can't say from where it cames, probbly due to mass, accel, speed.. measuring frequency might help... can't say where it comes from, I'd start by lowering both accel and jerk (yes both) significantly lower just to see if that's the culprit and if yes you can then change only one by one to find the proper settings, but it can be unrelated to jerk&accel and be caused by something else completely... I'm having these days some really unexplained issues (started similar to your second image) that I can't relate to anything so writing some g-code inspection tool attm to be sure it's not s3d related (after normal visual inspection I'd say g-code is ok and it's not s3d's fault but can't be sure of anything any more it's driving me crazy)...

anyhow it's bit weird that speed is same in first and second image, the issue (wiggly walls) from the first image is not caused by the overlapping perimeters.. not sure how fixing overlapping perimeters solved it, unless some change in speed of perimeter printing changed...

[Lorcoft]

So, after your first response I decided to investigate the jerk / acceleration settings. As a test I set the acceleration of both the X & Y to 100 and printed 2 test pieces with 1mm walls.

This is the X axis, the banding is entirely gone...

This is the Y axis, there are still some oddities on the surface, but I think these are mechanical. When I manually move the print bed, it feels like there are some ruts. I've tried rotating the aluminum extrusions 90deg to no effect. My next move is to replace the rollers and see if that makes a difference.

I don't know why changing the thin wall operation in S3D worked, but since it does I'll chalk it up to FM.

I left the jerk at 20, again i didn't want to change multiple values and confuse the issue.

Since I'm not worried about speed, I think I'm quite happy leaving the acceleration at 100 unless there's a good reason to change it.

I don't know if lowering the jerk speed is a good idea since I've read that lowering it can make the corners worse.