Problems with multiple UNION in Blender I am trying to combine many objects (in the order of hundreds) in BLENDER by the UNION operation (boolean modifyer, union). Correspondingly I wrote a small script that cycles through the objects, combining one after the other with the alwyays growing first object. This script works quite well for a few objects and operations (that I can also verify by hand). If their number rises, however, I get funny results. Usually several objects are missing from the growing "all-union-object". I assume that the UNION-function at some place messes up (as described in the www), and that all subsequent UNION-operations suffer from this. Is there any Modifier (or other way) that I could treat the single objects with in order that this UNION works? I have tested so far the REMESH and TRIANGULATE modifiers and also have scaled the single objects by different numbers in order to get rid of identical faces that might exist among the objects. Unfortunately, all this seems to change only the ultimate output and the appearance after combining a few objects. Cycling through the larger list of objects, however, always gives problems.
Any help is highly appreciated.

To the background: From another program I get initially in VRML/WRL many different spheres and cylinders that in part are identical and in part overlap. I cannot change this behavior and would like to have in the end one single entity (or object) like the UNION of all those little objects or the outer surface encompassing all those little objects. Importing to BLENDER (which works as expected) and combining all little objects by UNION (my question) would solve the problem (at least in theory if there were not the problem I am asking here ...). I am certainly not limited to this approach, so maybe there is also another one that would circumvent this issue with the multiple UNION in BLENDER ...
Join all the objects you want to unite using Ctrl+J
Create a new cube that contains all the joined objects inside
Use the Boolean Modifier on the Cube with Carve Solver and Intersect Operation