Mesh issue with CSG and Extruded Shape

I’m trying to use a CSG to subtract a hole from a larger part, where the larger part is a simple extrusion of a rather complicated bezier curve. The product/resulting mesh has this weird shimmering quality to it that the original extrusion does not. I’ve seen similar things when I have two surfaces in planar alignment, but this doesn’t seem to be that. When I export the mesh to STL, a similar thing appears, its like the calculated mesh has a ton of holes in it or its somehow bouncing between planes when it shouldn’t.

I just presume I’m doing something wrong and it isn’t an actual bug. Can anyone tell me what is going on? Thanks in advance!

the mesh name is “rotor”, it is the blue color

BAAAAAHHHHH! I pasted the wrong playground link:

Extruded Shape Examples | Babylon.js Playground (

Commenting out the sideOrientation in the extruded shapes seems to work, they were probably messing up the normal calculation:

EDIT: Btw, welcome to the Babylon community! :smiley:

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@carolhmj thank you so much, that looks so much better. I had spent a ton of time trying to see if the vertices were somehow being duplicated but I don’t think they were. but now I’m wondering if CSG is creating overlapping faces and I’m wondering if that is going to cause issues with the stl export and printing, but I can cross that bridge when I get to it. When I use an extruded polygon with holes the resulting mesh looks much simpler and cleaner. I’ll dig in and start another thread if I find something of note. Cheers!

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