Boolean Artefacts

I’ve just started a new model, two circles with a profile curve revolved between two curves (the circles). Then I boolean differenced blocks from the shape (extruded from red curves) and ended up with horrible artefacts as shown in the image. The actual model in wireframe is OK, the other end is fine.

Ouch, that looks bad, can you post the model? --Mitch

Yep will do Mitch, just built the model again using single curve then offset surface trimmed and caped the model then did the boolean and that worked fine ???

Boolean Fault.3dm (419.3 KB)

Ah, OK, there is something odd, your barrel volume is one single creased (kinked) surface instead of a 4 surface polysurface. Kinked surfaces usually make the render mesh go crazy, which is what you’re seeing. You can fix the existing object with DivideAlongCreases.

Rhino normally isn’t supposed to create kinked surfaces. Check your settings for CreaseSplitting, it should be set to SplitAlongCreases=Yes. On occasion it mysteriously sets itself to No, nobody knows why. In the past, plug-ins were suspected, but on Mac, there aren’t any, so that can’t be the case here.


Spot on Mitch it was turned off. I was doing similar work only a few weeks ago and it was working.