Hello All,
I’m attaching an excerpt with internalized data from a larger script.
My issue is that after a Solid Union operation I can not get Merge Faces cleanly.
For some reason a line still remains on one face. I thought maybe my initial boundary surface that I extruded was not planar, but not sure that’s the case.
I wonder if anyone has thoughts on this:
2024 1226_Facade 4-4.gh (21.7 KB)
I think your idea in (A) is: you have a middle surface, extrude it equally on both sides, then solid union them together into a single solid
I think the best solution (given couples of vectors have just opposite direction) is to move your surface half a vector in one direction (1), and extrude a full vector length in the opposite direction (2)
it makes things easier, uses one less solid boolean operation, and returns a final solid with already the minimum number of faces 
2024 1226_Facade 4-4_Re.gh (27.3 KB)
Alessandro,
I completely agree. This works cleanly.
But the question still remains - why Boolean did not work in my initial option?
Where did that line come from - that one remaining after Merge Faces…?
Maybe that’s because I created that segment of boundary curve by projecting onto a
cylindrical (curved) surface ? But that should not be a problem since the resulting boundary curve is still flat…
I think the boolean operation worked well in your initial definition
the problem of the faces not being merged together probably comes from the thing that the component is looking for adjacent coplanar faces
we might go into a sort of phylosophical question, like can they be co-planar if they are not even planar in first place… 
if the component description said it will merge adjacent surfaces with same Curvatures, then it should work, but by its description I assume it would not work on surfaces with any kind of curvature, they don’t lie on a plane so can’t be coplanar?
merge coplanar adjacent faces.gh (12.3 KB)
[edit] for clarity, the problem is with the non-planar surfaces generated by the extrusion of this curve:
Wow!
Your knowledge is so deep! Now it makes sense.
I did not realize that the merging faces had to be actual planes. I felt that even curved surfaces could be merged if the extrusion vectors for both objects are consistent (have same direction).
If I remove that extra edge the shape will remain the same, so that edge does not add anything really:
…but these are just me thinking out loud - the component works exactly how you explained.
