Blender colliders not functioning

Questions & Answers
1

Hello all,

I have a double connical cylinder rod imported from Blender into Unity. They collide with objects created in Unity just fine. But when 2 copies of the rod collide, they pass through each other. They do collide when one of the rod’s mesh collider is set to convex.

I also wrote a simple script gives a return value when these objects collide. I’m not getting any return value from the collison.

So, I have established that the colliders are not working at all when 2 copies of the objects collide with each other. Am I missing something painfully obvious here? I’m rather new to Unity and Blender as well.

2

You have given answer in your question itself.

They do collide when one of the rod’s
mesh collider is set to convex.

You need to set your mesh collider to be convex for it to collide with other mesh colliders. It is clearly stated in Unity Manual for Mesh Colllider:

Convex: If enabled, this Mesh Collider will collide with other Mesh
Colliders. Convex Mesh Colliders are
limited to 255 triangles.