during last weeks, sometimes when i use[solid union test.gh|attachment]solid union i have a problem, solid union tell me “boolean union set is empty” but 've checked my geometries and are ok.
i don’t find the problem
On rhino (and so grasshopper) it is always advisable to avoid solid booleans with congruent surfaces.
Your breps have some surfaces exactly overlapped.
Even on rhino doing a boolean union with those breps will take more time than expected.
Usually it is best to use intersecting breps/polysurfaces in solid boolean operations.
In your specific case you can just remove the faces and use the open loft (without caps) as this: solid union test_re.gh (428.6 KB)