Functional width of the conveyor, object also move on frame

Hello, I have physics conveyour in my program and when I place a cylinder on it completes works, but the can not only moves on the black part but also, but also on the frame. How can I change that objects only move on the black moving part, like a real conveyor.
Screenshot 2024-01-09 102141

Shift the physics-conveyors side rails to another link.
Set that links root node physic option to precise.
Change the sliding friction of the thus created physics entity to a higher value to have your products come to a stop on them.