I published this design on Thingiverse: https://www.thingiverse.com/thing:4582540/comments The design includes both source code and an STL. At least two users reported that the STL did not slice properly in Prusa Slicer. It sliced fine in Cura. Is this a problem with Prusa Slicer? Or is OpenSCAD screwing something up in the STL? I don't have Prusa Slicer to test with, and I would not be able to recognize an error in the STL file.

On Friday, September 25, 2020, 12:57:27 PM EDT, Douglas Peale <douglas_peale@comcast.net> wrote:  

I can confirm that it errors out with Prusa Slicer but Simplify3D has no problem with it. Meshmixer doesn't find any errors either. Prusa Slicer makes a good section of the model disappear! I don't have the OpenSCAD skills to make suggestions how to adjust your code to remove the Prusa failure. On Friday, September 25, 2020, 12:57:27 PM EDT, Douglas Peale <douglas_peale@comcast.net> wrote: I published this design on Thingiverse: https://www.thingiverse.com/thing:4582540/comments The design includes both source code and an STL. At least two users reported that the STL did not slice properly in Prusa Slicer. It sliced fine in Cura. Is this a problem with Prusa Slicer? Or is OpenSCAD screwing something up in the STL? I don't have Prusa Slicer to test with, and I would not be able to recognize an error in the STL file. _______________________________________________ OpenSCAD mailing list Discuss@lists.openscad.org http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

The STL has degenerate triangles and self intersections according to NetFabb studio. [image: image.png] Something in the design must generate vertices too close together for OpenSCAD. On Fri, 25 Sep 2020 at 18:13, fred via Discuss <discuss@lists.openscad.org> wrote: > I can confirm that it errors out with Prusa Slicer but Simplify3D has no > problem with it. Meshmixer doesn't find any errors either. > > [image: Inline image] > > > [image: Inline image] > > Prusa Slicer makes a good section of the model disappear! > > I don't have the OpenSCAD skills to make suggestions how to adjust your > code to remove the Prusa failure. > > > On Friday, September 25, 2020, 12:57:27 PM EDT, Douglas Peale < > douglas_peale@comcast.net> wrote: > > > I published this design on Thingiverse: > https://www.thingiverse.com/thing:4582540/comments > > The design includes both source code and an STL. > > At least two users reported that the STL did not slice properly in Prusa > Slicer. > > It sliced fine in Cura. > > > Is this a problem with Prusa Slicer? Or is OpenSCAD screwing something up > in the STL? > > I don't have Prusa Slicer to test with, and I would not be able to > recognize an error in the STL file. > > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >

I don't know the reason (it's really broken without reason) but after Rendering in OpenSCAD I exported it as AMF, this can be imported in PrusaSlicer and it works. Am Fr., 25. Sept. 2020 um 18:57 Uhr schrieb Douglas Peale < Douglas_Peale@comcast.net>: > I published this design on Thingiverse: > https://www.thingiverse.com/thing:4582540/comments > > The design includes both source code and an STL. > > At least two users reported that the STL did not slice properly in Prusa > Slicer. > > It sliced fine in Cura. > > > Is this a problem with Prusa Slicer? Or is OpenSCAD screwing something up > in the STL? > > I don't have Prusa Slicer to test with, and I would not be able to > recognize an error in the STL file. > > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org >

On 2020-09-25 18:56, Douglas Peale wrote: > I published this design on Thingiverse: > https://www.thingiverse.com/thing:4582540/comments > > The design includes both source code and an STL. > > At least two users reported that the STL did not slice properly in > Prusa Slicer. > > It sliced fine in Cura. > > > Is this a problem with Prusa Slicer? Or is OpenSCAD screwing something > up in the STL? > > I don't have Prusa Slicer to test with, and I would not be able to > recognize an error in the STL file. I ran the STL through AngelCADs polyfix application, it reports several zero area faces, one duplicated face and one nonmanifold face (=face with at least one free edge). After a couple of iterations it seems to be fixed though. $ polyfix Spade_Bit_Rack.stl Parameters: input_file = Spade_Bit_Rack.stl polyhedron 0 ================= volume=75230.9, dtol=0.01, atol=1e-06, maxiter=10 iteration 0: vertices=43296 faces=14432 warning: 31 zero area faces. warning: nonmanifold edges: uc(1)=43296 merged 36208 vertices removed 256 collapsed or zero area faces removed 1 duplicate face removed 1 nonmanifold face total changes=36466 no warnings iteration 1: vertices=7088 faces=14174 removed 1 unused vertex merged 14 vertices removed 28 collapsed or zero area faces total changes=43 no warnings iteration 2: vertices=7073 faces=14146 total changes=0 no warnings Summary: polyhedron 0: vertices=7073 faces=14146 : no warnings Writing: Spade_Bit_Rack_1.stl ... polyfix finished, time used: 0d 00h 00m 01s Another thing I tried was using OpenSCAD to convert your .scad file to .csg and then read that into my experimental .csg interpreter. It reports that at least one of your polygons has wrong winding order: ...Warning: 1st polygon2d contour staring at (0.000000,-1.000000) has wrong winding order I'm not sure what the polygon point winding order policy is in OpenSCAD (whether it automatically reverses wrong-winded polygons or not), but wrong winding order can get one into trouble. The documentation at https://en.wikibooks.org/wiki/OpenSCAD_User_Manual/Using_the_2D_Subsystem#polygon does not explain proper winding order clearly, but the examples show CCW winding order for the outer contour. Regards Carsten Arnholm