Boolean difference without intersection

Command “BooleanDifference” works fine when two solids have intersection.

I have large solid (let’s say sphere) and another smaller solid (sphere) which is completely inside of the large one. Trying to extract the small solid from the large one with command “BooleanDifference” but have the message “Objects don’t intersect. Nothing done”.
How can I extract one solid from another when they don’t intersect?

Many thanks in advance,

Hi Simon -

Rhino is a surface modeler, not a solids modeler. You could use tricks to achieve what you ask but why would you like to do this?


I made the figure for chess set and want to make it not solid but hollow. External surface has complicated shape and I am trying to create simple insert (like deformed cylinder or similar) inside my solid and then to extract it from the main figure. No intersection between figure external surface and surface of the insert is allowed.
Can you teach me how to do that?


What will your digital model be used for? For many uses separate internal and external surfaces are satisfactory.

Model is for 3D printing. Tried separate external and internal surfaces - end up with solid part, internal surface simple invisible for printer

Someone with 3D printing knowledge will need to provide advice.

Hello- many 3d printer systems will allow you to set a wall thickness for solids or offer to fill solids with a matrix of material.


This forum has a lot of results if you search the terms “Boolean difference hollow”…

This here might be helpful:

Boolean difference of a Box in Box - Rhino / Rhino for Windows - McNeel Forum

If you Flip the normals on the internal surface(which you can do once it’s in mesh form,) that will work. But no slicer actually needs that interior, it controls the wall thickness and ‘infill’ for voids.