Hi Ronni, can you please post the .3dm model file with the objects you're having trouble with?

If you want to keep it private you can e-mail it to me at moi@moi3d.com

Thanks, - Michael

Hi Ronni, thanks for sending the model through e-mail.

I sent you some more details in e-mail but the main problem is you will need to select
only the 3 faces on the interior area of the shell wall instead of the whole object, like this:



- Michael

Hi Ronni, then the next steps:

Select edges:



Fillet:



Draw rectangle:



Extrude:



Array circular:



Select extrusions and interior faces of thin wall:



Boolean union with "subset" face selection:



Draw circles:



Extrude, Move extrusions in Z:



Boolean difference:



Draw circles:



Boolean difference using circles as cutting objects, done:



- Michael

Super, vielen Dank Michael,
ich bin begeistert. Dass ich nur die einzelnen Flächen und nicht den Körper auswählen muss, darauf wäre ich nicht gekommen.

Gruß Ronni