Union operation not sucessful with joint of three cylinders made out of multiple sides


I am trying to make 3 way PVC Corner component in sketchup 2016 pro.

When I use 25 side it works well.

I have created a cylinder with 1000 sides and when tried to make union it does not work.

Please let me know what needs to be done ?


Don’t use such an obscenely huge number of sides. There’s no need for 1000 sides. Try something like 96 sides.


How does it not work? SketchUp must be doing something.
Not only is 1000 sides way too much (as @DaveR pointed out), but operations on intersections with ‘Union’ may create small mutual edges that hinder SketchUp in creating new faces. Or endpoints may merge, creating unwanted triangulation in new faces.


Thanks …@DaveR, Wo3Dan

I tried by with 100 sides and it worked well.

However, when exported to .stl and opened in mesh lab it shows faces on outer surface. This will appear as faces in 3D print object, I guess so. To make smooth surface I am trying to increase number of faces.

It really make endpoints with square/triangular holes. How to fix such issues ?

Best regards,
Makarand Acharya, India


Curved surfaces are always going to be made of small, flat faces. That’s just the way SketchUp works. It’s not an issue to fix in SketchUp.


If you get (square and/or triangular) holes as a result of the ‘Union’ operation (or whatever operation for that matter) try scaling up your geometry before the operation by 10x or even 100x. Scale down again after that to get back the actual size.