Union fails sometimes after copy or Save As

Rhino Rhino for Windows
1

Hello. New user here.

I have noticed that I sometimes get Boolean Union Failed after using Save As. So I have a bunch of objects that I want to union in preparation for exporting a mesh and 3D printing, but I don’t want to lose the original assembly. I first Save As to a new file before using Union, but it fails. Yet when I go back to the original file and Union the same geometry, it works fine. I have also noticed this when trying to copy objects, they will Union fine in the original file but not when pasted into a new file. My best guess is that the tolerances get changed, which makes some sense when copying objects from one file to another, but not when using Save As. Any insight would be most welcome.

2

Most likely, the difference is in the order you select the objects to union. If you are doing a SelectAll to select the objects, then saving will reverse the order. If you have an example of two objects with this problem, this is easy enough to check. In any case, please submit any failed booleans as bugs. Either post them here or if you don’t want the public to have access, send them to tech@mcneel.com.