Boolean difference of a Box in Box

Hi eveyone,
attached, please find a Rhino File of two closed volumes. One of them is completely inside of the other one.
I tried to create a Boolean difference, in order to create a “hollow” Box, but that didn’t work.
I need to do this in Order to calculate the volume correctly. (Not add the volumes, but subtract them from each other).
Is that generally possible?

Or more generally, how does Rhino handle hollow boxes with a “wall thickness”?

Thanks
Karl

BooleanQuestion.3dm (370.8 KB)

Trying to boolean difference the red from the black in order to create a “hollow solid”

Have a look at this thread

Given the number of threads on this recently, looks like I might need to make a Wiki page on this…

–Mitch

Hi Karl,

Have a look at this topic, it is are about the same issue you have:

HTH
-Willem

Hi Karl
Make a micro hole in outer polysurface

–Paolo

boolean Question_PN.3dm (365.8 KB)

Basically, Booleans do not work on objects that do not intersect.