Hi Ray, the problem is that Revolve does not know how to make an interior cavity like you want.

To do it you will need to do 2 separate revolves one for the outer skin and one for the inner and then use boolean difference.

That's how I made the attached version.

- Michael

Hi Mr Gibson,

Thank you for your prompt response. Are you going to have the opportunity to include this feature in 3DMoi version 5v as it is very important to me and others.

I appreciate your help so much.

Hi Ray, I've put it on my list of new features to work on in future versions but it is fairly complex and not likely to happen in the v5 time frame.

You can get the result you need currently by separating your profile into 2 curves leaving out the lines on the revolve axis:



You can then select both profiles and run Revolve which will generate 2 solids.

Then select the outer piece and run Construct > Boolean > Difference and select the inner
piece as the object to subtract. You can use a window select or click Edit > Hide to hide the
outer object to make it easier to pick the inner piece.

The result of the boolean will have the interior void region like you want.

- Michael