hi Koi, it's probably because the pieces are not quite fully aligned with each other, there is a sort of really thin slivery "shelf" like shape that would need to be created by the boolean. Things involving skinny fragments like this can make things difficult for the boolean intersection calculations:





I'll take a look at it some more later to see if I can give you any suggestions.

- Michael

Probably the best bet would be to scale the ring pieces slightly up or down so that they will have a simpler and cleaner intersection with the main piece without any sliver thin pieces getting created.

- Michael

Hi Koi, here's a version with those pieces booleaned in now. I scaled the rings slightly so they had a better intersection with the surrounding geometry.

3DM file attached.

- Michael

Hey Michael,
I understand... Thank you so much!! Also for sending me the right object :)

Thank you again and have a nice day!

Koi