Random solid layer where there is a circle??

[Bluemeane]

So I have seen this on two recent prints that use support, and have a 'circle', or 'hole' in the part.

It will after a few layers print a solid circle a few mm smaller that the hole, or circle in the part... Please see the images:

This one shows the support starting:

This one shows the random solid layer:

This one shows the support continuing on top of that random solid layer:

[Bluemeane]

Here is the part, please note that there is no solid floating circle in the middle:

[dkightley]

There's an issue in S3D where occasionally inconsistencies in the mesh are not interpreted correctly....and I think your model is one of the models that suffer from this.

An easy fix.....change the layer thickness in your profile by 0.0001 and try the slicing again.

The proper fix.....run the model through the online repair service: https://netfabb.azurewebsites.net/

[Bluemeane]

I will give it a shot, sounds legit. However I have printed this in the past in S3D without dual extrusion and not had this happen....

[burtbick]

That buglet probably explains what I had happen today. I've sent the STL file on to S3D for them to look at.

In my case I was working on printing a calibration model that I created to work on getting holes to print at the proper size.

The model had been printing just fine, but I made one test where I changed the size of an 8mm hole to make it slightly larger. When that happened the outer edge of the 8mm hole moved so it was touching the outer edge of a 10mm hole that was next to it.

When S3D sliced the stl file it printed a single layer about 50% up from the bottom of the hole. For a test I sliced the same stl file with CURA and there was no problem, CURA did NOT print the single layer covering the hole as S3D did.

I then went into FreeCAD and changed how I had the 8mm circle constrained so it will always attempt to keep some addition distance from the 10mm hole.

S3D was able to properly slice the model again after I made that change.

I'll keep in mind the trick with changing the layer hight as suggested above if I see this in the future.

Note also that I had pulled the model into netfabb before handing it off to S3D and netfadd didn't find anything wrong with the stl file, and S3D's tests also said that the model file was fine.

Burt