All: I have a very strange rendering problem where I am trying to add a cylinder to an STL file. (Essentially this is to create a flat bottom for 3d printing). Below is my openscad code and attached is the STL file. The issue is when I do F5 the model looks like I want it to. When I do an F6 the bottom ends up hollow. It actually looks more like a difference than a union. See attached image. Reversing the STL and Cylinder does not make a difference. What am I missing? //use <write/Write.scad> baseSTL = "RECYCLING_BIN_ASM.stl"; //End settings module can(){ //move the stl to center the text at 0,0 rotate([90,0,0] )translate([0,3,0]){ scale([0.05,0.05,0.05]) import(baseSTL); } } union(){ cylinder(r=11,h=4,$fn=120); can(); } <http://forum.openscad.org/file/n10999/RECYCLING_BIN_FlatBottom.png> RECYCLING_BIN_ASM.stl <http://forum.openscad.org/file/n10999/RECYCLING_BIN_ASM.stl> -- View this message in context: http://forum.openscad.org/Strange-rendering-issue-with-STL-and-added-object-tp10999.html Sent from the OpenSCAD mailing list archive at Nabble.com.

On 01/10/2015 04:25 PM, bytemedwb wrote: > The issue is when I do F5 the model looks like I want it to. > When I do an F6 the bottom ends up hollow. It actually looks more like > a difference than a union. See attached image. > Reversing the STL and Cylinder does not make a difference. > What am I missing? > Normally those issues are caused by broken STL files. But in that case it actually looks more like a bug. The STL does not show any errors in blender or netfabb. And the render using the OpenSCAD 2014.03 release version does produce a different but also strange result. I guess that needs some deeper investigation... ciao, Torsten.

This is just a guess: remove the scale([0.05]) and increase the radius of the cylinder by 20. And see what happens. 2015-01-10 17:09 GMT+01:00 Torsten Paul <Torsten.Paul@gmx.de>: > On 01/10/2015 04:25 PM, bytemedwb wrote: > >> The issue is when I do F5 the model looks like I want it to. >> When I do an F6 the bottom ends up hollow. It actually looks more like >> a difference than a union. See attached image. >> Reversing the STL and Cylinder does not make a difference. >> What am I missing? >> >> Normally those issues are caused by broken STL files. But in that > case it actually looks more like a bug. > The STL does not show any errors in blender or netfabb. And the > render using the OpenSCAD 2014.03 release version does produce > a different but also strange result. > > I guess that needs some deeper investigation... > > ciao, > Torsten. > > > > _______________________________________________ > OpenSCAD mailing list > Discuss@lists.openscad.org > http://lists.openscad.org/mailman/listinfo/discuss_lists.openscad.org > -- stempeldergeschichte@googlemail.com <karsten@rohrbach.de> P.S. Falls meine E-Mail kürzer ausfällt als Dir angenehm ist: Ich probiere gerade aus kurze Antworten statt gar keine Antworten zu schreiben. Wenn Du gerne mehr lesen möchtest, dann lass es mich bitte wissen. P.S. In case my e-mail is shorter than you enjoy: I am currently trying short replies instead of no replies at all. Please let me know, if you like to read more. Enjoy!