Luban slicing bug?

first, allow me to show my simple design in Sketchup:

a couple of simple columns by pulling a circle up, placing horizontally.

This is what I see in Luban

This is what the slicer did (I didn’t realize the small plug becomes two notches until I print them)

This is what I realized gone wrong and stopped the process.

This is weird a figure created by a simle cylinder which comes out in two different pieces
I have already performed the repair as suggested by Luban.

I am going to slice by Cura and try to see if there are some glitch in my drawing.

Luban (and Cura) won’t render features that are smaller than the nozzle diameter. My guess is that the model is hollow, with thin walls. Although if that was true, it wouldn’t’ve printed anything, so I’m not sure. The gray ghost outline on the preview is what I see when something is too thin to print.

This applies only to Cury version <5. See Arachne engine remark in the release note of version 5.0.0:

However, the issue seen here is most likely unrelated to that.

First thank you to your suggestion. :slight_smile:
My works are not big one, the diameter of the bugged end is 6mm, but the bigger one is just 8mm
it works fine for the 8mm but something missed in the middle of 6mm, which is even bigger than the 2 ends.
This is my query
Later I repaired the figure in Luban, and then export the repaired stl to Cura, it just works fine.
BTW, the gray ghost outline is just I scroll down the layers in perview mode, you can see the bugged end is doing good, red, green and yellow appear means the slicer could tell the different parts.

Something more is that, I printed them in the first trial vertically as there is a bigger column with exactly the same height, I just put them together to save my time. However in the middle, maybe some filament wrap up and crashed by the printhead, all the columns turned into a mess:

So I divided them into 2 separated parts and printed them horizontally.
In the vertical position Luban slilces correctly, that why I think something gitch in Luban.

I have occasionally had similar issues with slicing sketchup models. Check that all your faces are correct (that they are all the “white” face, and that the “blue-gray” faces are inside). This can sometimes help. Secondly, move “inside” the sketchup model .I’ve found internal lines and faces can give both cura and luban grief. If that’s the case, cura has an option to ignore internal geometry and create one solid. This might help. For me, different combinations of the above have helped, but sometimes, for reasons completely unknown, I’ve had to redo the model in sketchup. :frowning:

Agree, I didn’t consider the face vector and the internal. I will work it out.
However I just create the cylinder by pulling a circle up and then offset and pull again, there was no reason to have internal geometry for my consideration of having bugs.
It should be one of the simple structure for any slicing software :smirk:

Key word is “should”! LOL. I also wonder if it’s a precision issue in sketchup, as I’ve never had any luck working less than 0.1mm increments, so I wonder if it “tears” the structure? The other thing I’ve done is created the model in sketchup at 10x or 100x actual size, then scaled in the slicer (10% or 1%). Can’t remember if this fixed this issue, but it helped with accuracy, nice round parts, etc, as I can have more sides on a model.