How to make a passable tube?

Hey guys

What I want to do is actually really simple (I thought). The player should be able to fall trough a Tube or Pipe which I made in Fusion 360 and exported as .obj (also tried other formats). The thing is the player needs a mesh-collider (because otherwise it would not be precise enough) and now I cant fall trough the pipe. Because to be able to collide with each other as far as I know they both have to be convex enabled. But a Convex tube/pipe removes the whole in it... Has anyone an idea how to solve it? I appreciate every help! (When the player has a box collider and the tube isn't convex, everything works fine)

Kind Regards
Nik

 

The tube itself doesn't need to be marked as convex. Simply un-check the convex option in it. All other objects that have to collide with the tube do need to have Convex enabled.