In most models “seams” show where they aren’t desired. I’m posting this on this forum because I’m relying on Hidden view, which I believe is specific to Va.
Here’s a corner in shaded and in Wireframe view. No 90 degree “seams” on the face of this door frame corner. (There’s no diagonal seam either, but every solid display mode erroneously shows those - let’s focus on the unwanted 90 degree seams.)
Nor 90 degree seams there either.
But here in the Hidden view (please note its display settings also) there they are, as they are in most every door frame I model. (This door frame happens to - unrealistically - wrap around a curve, but this issue happens with orthagonal door frames also.) Can I get rid of these things?) They are interpreted as an undesirable decorative feature.:
@djhg In that model I can see the seams at door frames corners, which is normal because you have got there 3 different polysurfaces for the frame. If you make a boolean union, you won’t see the joints:
That doesn’t work here, Francesc. I continue to get both the diagonal seam and the two horizontal lines visible in the last image on my o.p. (Were you able to prevent display of the tangent seam in the curb shape? I can’t get rid of that either.)
I notice that I’m using a version of 2.8 published on July 15th, while the latest one available for download appears to be from May 13th. Maybe that’s the issue. Apparently my drivers are up to date.