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Deformation of a cylindrical surface when cutting 2 holes on it at an angle of 45 degrees (by al-vo)
Many thanks to all the authors for a wonderful convenient program!
Question. When cutting holes by rotation on the cylinder, a visual change occurs in the cylindrical surface between the holes. It seems to be pulled towards the center. Perhaps this is a known issue?
Thu Jan 19 2023, 01:20:28, download attachment 1.slvs
(no subject) (by Andrew)
Saw the same effect, but only at some orientations of the view. It also shows on the stl export regardless of orientation. A work around is to use force to NURBS in the last group.
Thu Jan 19 2023, 06:06:25
(no subject) (by al-vo)
Unfortunately, the use of "force NURBS surfaces to triangle mesh" leads to errors in the exported STL file and a significant increase in the size of the SLVS file itself.
If "red lines" and "bare surfaces" in 95% of cases it is clear how to fix it, then occasionally problems with surface deformations ("white lines") do not yet lend themselves to a logical explanation.
Fri Jan 20 2023, 00:34:25
(no subject) (by Andrew)
The only visible effect on the exported stl that I see is segmentation of the perimeter, and this is controlled by 'export chord tolerance' in the configuration page. Also, you can turn force nurbs ... on and off, and so only turn it on for the export, and off otherwise, and avoid file size expansion of the saved slvs.
Fri Jan 20 2023, 09:48:33
(no subject) (by ruevs)
This is a rather interesting "quirk" of the triangulation algorithm. I've not looked at those parts of the code much, but I will create an issue for this on GitHub.
Fri Jan 20 2023, 18:54:10
(no subject) (by al-vo)
Andrew, thanks for the help! The idea works.
Ruevs, a still similar situation with a “white crack” in the attached picture.
Sat Jan 21 2023, 05:49:41, download attachment 2.jpg
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