More Boolean issues with two closed polysurfaces

I am trying to boolean these two objects and it is not working. Presumably this is because there are shared faces. Do I really need to go around and delete all the shared faces or is there an easier way to join these two objects?


Boolean_union_test.3dm (2.5 MB)

Most likely that is because one of them is not a closed polysurface (not a solid). I added a missing surface, trimmed a little, and joined it back. Now Boolean should work.

Boolean_union_test.3dm (2.5 MB)

Hi Revel - the larger object is not valid (SelBadObjects)

  • try:

Delete the surface
Select the curves from DupBorder
Join it back into the object, run Check to verify.

But, the Boolean is still unlikely to work - it did not, here. The easy way out is probably to ExtractSrf & Delete all the coincident faces and then simply Join the two parts.


Thank you, Pascal. I have two valid polysurfaces, but, how do I do the above?



could you take another look at this, and / or describe to me how to go about joining these?

I tried deleting all coincident faces, and then joining, to no avail.



3 closed polysrf.3dm (3.7 MB)

Hi Revel - it looks to me like it all hooks up if you remove the coincident faces, except in a couple of locations - seems to be very slightly offset here:

Also, many of the surfaces that are chopped up into the three pieces are the same surfaces and can be untrimmed and retrimmed to avoid the seams where the three parts go together. I don’t know if it is with the effort but just so you know…


Yes, I am at the same stage here, see attached model. So in the case where you have two curves slightly offset like that, what is the best recourse? PlanarSrf? SrfPt? Cap?



3 closed polysrf(joined).3dm (2.5 MB)this case

I guess the easiest is to extract all the surfaces to the right, Move them, snapping to end points to close the gap on the left. That opens a gap to the right, but the surfaces there all appear to be linear in the side-to-side direction, so you can move the edges of the main object’s surfaces that are there over. (Sub object select the edges, Command-Shift click or window.)

3 closed polysrf_PG.3dm (2.7 MB)


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