Hi Pilou,

re:
> A simple 3 big extrude
>
> Then 2 Boolean Merge, then Boolean Union don't make the trick ?
>
> http://moiscript.weebly.com/uploads/3/9/3/8/3938813/tubeintersection_pilou.3dm

Nope, not quite - your version does not have all the interiors fully cleared:



- Michael