How to delete intersecting surface inside geometry

Hello everyone,

I am having issues with creating one solid geometry. So far I have created lots of individual polysurfaces into a few bigger closed polysurfaces, but when I try combining these into one entire one, it becomes an open polysurface and I can’t send it for toolpathing. The geometry itself is too complicated to manually combine every single thing at a time.

Attached is the file I am working on right now. I want to combine all 4-sided buildings as one solid, and the rest of 4 turrets as individual solid groups.
I would appreciate any help, it’s been a few days of struggling here…
I uploaded 2 files, as it was too big to upload as one. Please import the other to view the entire piece together.

Many thanks,
Main_Solid_Oct.07.3dm (18.3 MB)
Main_Solid_part 2_Oct.07.3dm (2.6 MB)

Forgot the attachment?

Oh sorry! Hi @Helvetosaur, here are the files for you!

Hello- it looks to me like the problem is that intersections correspond to surface edges in a few locations, which the intersector seems not to like - you end up with incomplete intersections at these locations:

As far as I can the objects are ok and it should work but at the moment the best I can do is put the examples on the pile for the developer. I guess some tedious ‘by hand’ trimming of surfaces may be the way out.