Why do these surfaces not properly create the full curve intersection?
It appears that the middle surface might be the problematic one. The side surfaces intersect the middle surface up to the mid-line isocurve on one edge, then from the other edge to the mid-line isocurve.
These were offset surfaces, loosely built at 0.05 inch tolerance, from primary surfaces that made a bigger closed polysurface.
Rhino 8 file attached.
Thanks
Intersection partial error.3dm (175.5 KB)
Here’s another weird one. Again, an offset surface, with a loose tolerance of 0.05" from a primary trimmed surface that formed part of a closed polysurface. There is a line I made to trim off part of the offset surface that ended up funky. However, when I pulled that line to the surface (to trim the surface) the pulled curved does not touch the surface at all. What is going on? Is it because the surface is not a single span?
Pulled crv completely off surf.3dm (139.1 KB)
the points circled here are very close to tangent to the adjacent surface. (turning on the points for a surface is a good way to see what is really happening.)
this makes extending the surface troublesome as they don’t really intersect, they go very close to coplanar (not actually coplanar, but for lack of a better term, they are lying on top of each other)
you have a few options…
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split by isocurve to model “gaps” and then close them up with blendsrf or something similar.
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point edit your surfaces to get a true intersection
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project curves to use as trim curves, model gaps, and close up
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use filletsrf and then trim with those surface edges. (you will still have some hand work to do with this solution
can’t quite figure out what is happening with the second one… I see a curve and trimmed edge, but not the original curves or any context of what you’re trying to do?
can you provide some more details?
For the second example, zoomed in at the red arrows on the earlier image, I wanted to trim this offset surface, as it did not correctly offset within the overall polysurface. So after extracting it, I drew a line from two edge points. Then I pulled that line and tried to trim the surface. But that pulled curve is completely off the surface, at least in the viewport. So how is the surface bad?
It’s actually easier to see in wireframe:
