I have two closed polysurfaces, one that is a cut out of a site that I need to boolean difference from the base, however, I have tried every technique to get it boolean differenced, but nothing seems to work. Please help me, thank you!!!
260209_Site Model_SiteCutOut.3dm (8.8 MB)
one issue might be that there is already some far from origin issue here:
(check other topics “far from origin”)
min = 717608.477,209.575,1827812.695
max = 717886.250,230.516,1828444.143
dimensions = 277.773, 20.940, 631.448 feet
and - boolean operations don’t like overlapping, nearly identical surfaces.
you have quite a few of them
for boolean difference to work, a single (or a set of) closed curves are needed - and you can check if this can be found by intersecting both parts.
this is what i get:
how to solve your issue ? - either work with single surfaces, trim join.
or - my guess this is the way to go here:
_intersect to get the red curves above.
_explode
pick the elements you need to get a nice closed curve / loop.
use this poly-Curve to trim both the base and the cutter, join.
wait - i ll give it a try…
more issues:
even some more issues - check _mergeAllCoPlanarFaces.
deleted some faces and _cap to close them again…
this is befor the final join: (green is the cutting_crv
the final version:
260209_Site Model_SiteCutOut_tp_fix_01.3dm (15.8 MB)
Hey @MayaStudent 
Your site model has some issues?
First, I ran the SelBadObject command and it found some, which I deleted. Then the SelDup command, I think you had overlapping faces. Also, there was some weird triangular shape sticking out of the bottom of the site model. Deleted that and closed a hole with Untrim. No more naked edges.
Second, given your subtracting solids have surfaces that are shared/flushed with the site solid, a slight increase of their boundaries (DupBorder + {small} Offset + Patch + Trim + {solid} Extrude) makes the solid difference work.
In case it helps:
260209_Site Model_SiteCutOut.3dm (10.4 MB)
