Not sure why you have problems with dimensional accuracy because objects designed in OpenSCAD are the size I specify in the code, so I don't need to measure them. One thing to be aware of when making rounded objects by hulling circles, cylinders and spheres is they should always have a multiple of 4 vertices, so you get a vertex exactly on each axis to align with the sides of your box. Otherwise it will be slightly too small. See https://github.com/nophead/NopSCADlib/blob/52e9c1d7fd97555a03ea9c029887902d28aefae5/utils/core/global.scad#L69 Also I replace the OpenSCAD sphere with my own that has vertices at the poles. See https://github.com/nophead/NopSCADlib/blob/52e9c1d7fd97555a03ea9c029887902d28aefae5/utils/core/sphere.scad#L23 On Wed, 12 May 2021 at 11:00, Terrypin via Discuss < discuss@lists.openscad.org> wrote: > > > > ---------- Forwarded message ---------- > From: Terrypin <T.pinnell@btinternet.com> > To: discuss@lists.openscad.org > Cc: > Bcc: > Date: Wed, 12 May 2021 00:32:51 -0700 (MST) > Subject: [OpenSCAD] Re: Merging sub-assemblies? > Thanks, that tool looks fascinating. I’ll try it next time I need to > reassure myself about dimension accuracy. > > The situation in the case I described was because in exasperation I was > resorting to trial and error after losing control of my intended geometry! > I made a better job of it on my subsequent more methodical attempt. > ------------------------------ > Sent from the OpenSCAD mailing list archive <http://forum.openscad.org/> > at Nabble.com. > > > > ---------- Forwarded message ---------- > From: Terrypin via Discuss <discuss@lists.openscad.org> > To: discuss@lists.openscad.org > Cc: Terrypin <T.pinnell@btinternet.com> > Bcc: > Date: Wed, 12 May 2021 00:32:51 -0700 (MST) > Subject: [OpenSCAD] Re: Merging sub-assemblies? > _______________________________________________ > OpenSCAD mailing list > To unsubscribe send an email to discuss-leave@lists.openscad.org >

/"Not sure why you have problems with dimensional accuracy because objects designed in OpenSCAD are the size I specify in the code, so I don't need to measure them."/ That's my aim too, but I did explain in my reply a few hours ago. Thanks for the suggestions about hulling which I'll study. Meanwhile just about to post my own 'hull' result. -- Sent from: http://forum.openscad.org/