Do I need all three rails?

With three rails, if you stack and stagger the trolleys from top to bottom in a tier formation, you can achieve a minimum of 1.00” of spacing between lines. With two rails, that goes up to 1.50”. With a single rail, the minimum spacing is 3.00”.

For a lower trolley density, up to 6 units, the laser stand off and ring mount can be flipped on half of them, allowing the lasers to get closer to each other, but that is again not repeatable for a full load such as 14 trolleys.