Cannot Add/Subtract/Intersect

Problem23.3dm (516.6 KB)

In the attached file I have two solids. I would like to be able to subtract the black from the cyan. However, I get “Boolean difference failed.”

The same thing happens for union and intersection. I was wondering why?

Intersection failure- the first line of diagnosis on failed Booleans is to Intersect the objects and then inspect the resulting curves - in this case there are two locations where the curves are open where they should be closed. Still poking.

-Pascal

Thanks for the tip (I save save all of them you folks give me in a file).

I am puzzled why the problem occurs where it does. The shapes appear rather benign.

I think it happens because the intersection is exactly on a knot line of the revolved surface.
Nope.
The cyan surface is too sparse - try this:

ExtractSrf the revolve.
InsertKnot, Direction = Both (though I suspect V is the one that counts). Hit Automatic a couple -three times. Join it back up and Boolean away…

(@bigjimslade - fixed, by the way, in the next version (6) of Rhino.)

-Pascal

Thanks,

I was having a similar problem on another assembly and tried this on that one as well. I was trying to Boolean Union a sphere to a part and that was refusing as well. I did this on the sphere and it corrected.

Problem24.3dm (117.7 KB)