As a newbie, and coming from Form Z. I am struggling to get my head around the problems Rhino 8 has with Boolean operations. I have created a simple roof and just need to boolean union the gables. I know that I have some coplanar faces on the base but even if I scale up, the booleans still fail. I have tried all the workarounds but without success. There must be a simple answer? I am working on Rhino Version 8 (8.33.26188.13002, 2026-07-07), on a Mac OS 26.6. Attaching a file. Thanks for the feedback.
If you select your main roof surface you will see it described in the command line as an open polysurface. It ought to be closed - and needs to be in order to boolean - so that is your clue. Isolate the roof, change to wireframe mode and explode it. You will find two unwanted internal surfaces like this:
Thanks for picking up on my open poly surface.
This is where I have a problem with Rhino 8 and its Boolean operations. When Boolean Unioning it sometimes does not remove surfaces that then become internalized. I exploded, removed the surfaces and Joined. The first joining process made a mess and gave me some Naked Edges. I tried to repair these naked edges using Patch, JoinEdge etc. But I just went from Bad to worse. So I retracted my steps unjoined and rejoined- and it worked???
This is where I have a problem with Rhino, it is not very forgiving and then to repair the model it is not straight forward if things start to go in the wrong direction.
The Rhino community is unbelievable and I am hoping that I can move over this hump. Doing a course in September
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