03-12-2009, 12:07 AM
I was mistaken, the couplers I thought were tight lock are the shelf type which have the numbers of 118 for full shelf and 119 for the 1/2 shelf, or vice versa. With the modules we often have a problem with dips and bumps at the joiner tracks between modules, and long rolling stock like full length passenger cars are the most susceptible to uncoupling. The guys who have tried the shelf couplers have found that they do stay coupled better over rough track than the standard #5's that they were using. I should also mention that shelf couplers are not prototypical for passenger cars. The shelf type are actually designed for use on tank cars and any other car hauling hazardous materials, but they do work well to keep passenger cars coupled.