Hi, I'm new to OpenSCAD and am starting with very simple stuff: modifying an existing design that I import from an STL file. Rendering with F6 (required to produce an STL file that I can print) fails as follows: I've seen that a number of other folks are facing the same issue, but they don't seem to have found a solution. I'm currently running version 2016.10.04 (git 7e0935d) (on 32-bit Windows) but the problem also occurs with 2015.03-2. Attached: my SCAD file Bouton_robinet-2.scad <http://forum.openscad.org/file/n19332/Bouton_robinet-2.scad> and the imported STL file Bouton_radiateur.stl <http://forum.openscad.org/file/n19332/Bouton_radiateur.stl> (source: http://www.thingiverse.com/thing:83544 <http://www.thingiverse.com/thing:83544> ) I've tried "cleaning up" the imported STL file various ways, to no avail. How can I solve this issue? -- View this message in context: http://forum.openscad.org/Another-case-of-ERROR-CGAL-error-in-CGAL-Nef-polyhedron3-CGAL-ERROR-assertion-violation-tp19332.html Sent from the OpenSCAD mailing list archive at Nabble.com.

For simple things like this (drilling a couple holes in an existing stl) I have had decent success with using TinkerCAD (free simple In-browser CAD, it can import and export STL). There are a lot of STL files that OpenSCAD does not process (even after mesh repair tools like NetFabb). I have spent many hours trying to fix it STL files into something openscad will like, and most Of the time I haven't been successful. > On Nov 22, 2016, at 11:55 PM, sba923 <oscadforum.nospam4sba@xoxy.net> wrote: > > Hi, > > I'm new to OpenSCAD and am starting with very simple stuff: modifying an > existing design that I import from an STL file. > > Rendering with F6 (required to produce an STL file that I can print) fails > as follows: > > > > I've seen that a number of other folks are facing the same issue, but they > don't seem to have found a solution. > > I'm currently running version 2016.10.04 (git 7e0935d) (on 32-bit Windows) > but the problem also occurs with 2015.03-2. > > Attached: my SCAD file Bouton_robinet-2.scad > <http://forum.openscad.org/file/n19332/Bouton_robinet-2.scad> and the > imported STL file Bouton_radiateur.stl > <http://forum.openscad.org/file/n19332/Bouton_radiateur.stl> (source: > http://www.thingiverse.com/thing:83544 > <http://www.thingiverse.com/thing:83544> ) > > I've tried "cleaning up" the imported STL file various ways, to no avail. > > How can I solve this issue? > > > > > > -- > View this message in context: http://forum.openscad.org/Another-case-of-ERROR-CGAL-error-in-CGAL-Nef-polyhedron3-CGAL-ERROR-assertion-violation-tp19332.html > Sent from the OpenSCAD mailing list archive at Nabble.com. > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org

Normally this is a bad STL. Normally with Netfabb and Meshlab I can find something wrong easily. Not so with this one. Having had a very close look I can't find anything I normally would expect. I only found one anomaly, and I don't know what it means. In Meshlab, I selected Render/Color/per-face and got this: <http://forum.openscad.org/file/n19342/td19332_per_face.jpg> All faces black but the one red. So there may be something wrong, but it is beyond me. ----- Admin - PM me if you need anything, or if I've done something stupid... Unless specifically shown otherwise above, my contribution is in the Public Domain; to the extent possible under law, I have waived all copyright and related or neighbouring rights to this work. Obviously inclusion of works of previous authors is not included in the above. The TPP is no simple “trade agreement.” Fight it! http://www.ourfairdeal.org/ time is running out! -- View this message in context: http://forum.openscad.org/Another-case-of-ERROR-CGAL-error-in-CGAL-Nef-polyhedron3-CGAL-ERROR-assertion-violation-tp19332p19342.html Sent from the OpenSCAD mailing list archive at Nabble.com.