Simplify3D User Forum

Why would S3D do this, area indicated by yellow arrows, on the first layer. It breaks the first layer into two sections which makes the surface of the print look bad. Remaining layers print ok or fill in to the perimeters without the break.

Model has been checked and is error free.
Surface is flat and 100% on the bed.

Tried three different printer profiles and materials and get the same thing.
Tried a variety of settings changes and it doesn't change.

In my experience, things like that are typically caused by odd changes in the topology of the STL file, but it's hard to make any better guesses without being able to look at the exact setup for your print. Can you post the factory file for the print?

S3D-Jason wrote: ↑Mon Jan 22, 2024 9:07 am In my experience, things like that are typically caused by odd changes in the topology of the STL file, but it's hard to make any better guesses without being able to look at the exact setup for your print. Can you post the factory file for the print?

It is a customer file so I can't share it.
The model is very straight forward with no issues. Model check in Netfabb.

The model slices fine in Bambu, Orca and QIDISlicer.
Settings for the printer are basically defaults 0.2mm layer height, 0.4mm nozzle and printer is a Prusa MK2.5s.

wirlybird wrote: ↑Mon Jan 22, 2024 10:10 am

S3D-Jason wrote: ↑Mon Jan 22, 2024 9:07 am ...odd changes in the topology of the STL file...

It is a customer file so I can't share it.

Then at least share an image of the section in question. It's obvious there's some thin wall feature or a
height change in topology coming, because what you're showing in your first post highly suggests this...

The model is very straight forward with no issues. Model check in Netfabb.

So because there's no potential errors inside a model we now know the topology of the model in question? Interesting...

The model slices fine in Bambu, Orca and QIDISlicer.
Settings for the printer are basically defaults 0.2mm layer height, 0.4mm nozzle and printer is a Prusa MK2.5s.

Doesn't tell too much because depending on the model features I'm pretty sure other slicers can produce the same unwanted
behavior.

Example:
Object Sliced using settings A: ...and settings B: But for some reason people often simply don't want to deliver neccessary information to help them in a troubleshooting forum...

Or maybe it's a bug report and I'm just missing the details, like steps to reproduce this issue. Who knows. All I can say with the
information given: Check your settings, adjust them to fit the unknown object in question so it gets printed in a way you like...

The model is as it looks. It is 5mm thick and the shape is what you see, it does not change as layers increase. Just a flat model at that end. No change in geometry.
I tried a number of settings changes including layer height, number of top/bottom layers, number of walls, extrusion width, speeds etc. Nothing seemed to make any difference.
Tried my profiles for three different printers and got the same results.
Ended up printing it using a different slicer and it printed fine and no issues with the resulting print.

No idea why it did that. I did not think to try it in version 4 though, so I just checked it and it slices fine. No issue.
So this issue is limited to V5. I am not surprised as this is not the first slicing oddity I have seen in V5.

May be one of those things we never find an answer to!

If the part is literally just a constant rectangle with one cutout, I think it would be easy to share with our team. You can email it directly to us at the link below if you don't want to share it publicly.
https://www.simplify3d.com/contact-us/

Without providing the actual files though, I doubt anyone will be able to provide many more suggestions...

S3D-Jason wrote: ↑Wed Jan 24, 2024 1:14 pm If the part is literally just a constant rectangle with one cutout, I think it would be easy to share with our team. You can email it directly to us at the link below if you don't want to share it publicly.
https://www.simplify3d.com/contact-us/

Without providing the actual files though, I doubt anyone will be able to provide many more suggestions...

I have determined it is an issue specific to V5. I sliced the same file in V4 and it is fine. Also slices fine in other slicers.
As we know, V5 has some slicing anomalies which show up from time to time and are not explainable.
I'll have to write this off as one of those.

I've seen lots of files that sliced fine in one program, while failing in another. In many cases, it was still a problem with the mesh. Depending on the settings, different mesh errors can trigger issues in different places.

I still think it would be best to let our team investigate the file. Even if it's an issue, there's no way our team will ever be able to fix it without providing example files. An extruded rectangle should be an easy one to share, and as I mentioned you can email it privately if you prefer.