Rigid Body Mesh Collisions: Objects falling through each other I have a scene  that I need to run simulations on, and quite a few of the collision shapes need to be set to mesh. This works fine for most objects but there are some that are acting weird, basically falling through each other.

Following the tips here and here, I have tried to solve this by:


Increasing the number of steps per second
Applying the object's scale
Tweaking the boundary margin
Subdividing the meshes
Flipping Normals


Further, the masses are similar and the dimensions are reasonable.

None of these tweaks have helped. Though the simulation runs fine if one of the objects collision bounds is set to convex hull. Is there something I can do to the meshes to make this work?

Example file:
As @m.ardito and @Rich Sedman pointed out, the solution is to remove doubles: Edit mode, select all, Remove Doubles. 

The simulation now runs fine