Sigh . . . you can be a good zookeeper for many years, but add one more hippopotamus and there's trouble. What the heck am I talking about? OK, here's the story.
The most beautiful train I run is my California Zephyr. I have been running eight of the gorgeous Atlas O Zephyr cars with three dual motored Lionel Legacy F units and three dual motored Lionel Legacy Denver & Rio Grande F units. The six motors come in handy hauling those eight cars up a long 2.2% grade. Even though the cars barely make it through O-72 curves and turnouts, I barely had any derailments. Once in a while if I was clumsy with some adjacent freight cars and nicked an Atlas O switch, the point rails might move slightly and the Zephyr cars might pick the points causing a derailment. The cars NEVER separated nor were there any issues with the arrangement of the cars. The build quality, especially the trucks and couplers was top notch. Even though the cars are very long and even though they are extremely close coupled and the diaphragms almost touch, they rarely if ever lost it on a curve. All was fine in Zephyr land.
Then, last week, I added the incredibly gorgeous diner and 16 section sleeper. The hippo was in the room. Over the course of a week I was not able to run the train around the layout one time without a major derailment. When I say major, I'm talking derailments in covered sections of the layout that a very small person could not get to, and I am a hippo type myself. Time after time, no matter how carefully the train entered these sections there were derailments. Tracking down the culprits was maddeningly difficult. First, the cars are close coupled so separating a car that is half in a tunnel is an exercise in deep breathing. Lifting the end of one car to uncouple it from its adjoining car is extremely difficult. The end of one car lifts the other. Time after time I had to fish 80+ foot cars out of tunnels. Yikes. After a dozen or more episodes I have identified the problems. Notice the plural.
Problem #1: Train weight and poor coupler design.
Eight cars run fine. Add two more cars and you increase coupler strain on the head end cars. So?
big deal. A locked coupler is a locked coupler. Noooooo. The moving knuckle of the Atlas O couplers barely locked together owing to the short length of that moving knuckle. The wide end section of the coupler pocket has been designed too wide. Though the moving knuckles of the couplers will latch and stay closed, cars STILL separated on level track even though coupler height is dead correct. Cars began to separate on dead level track and I would run over to see which coupler opened. Both were closed. It must be track irregularities then. Sooooooooo, I ran the train over and over the same section and discovered the weight of the ten cars causes the two locking knuckles to separate. Whoa . . . To test this I gently tugged on two coupled cars. Fine. As I increased force, the cars separated while the knuckles stayed closed. Ayyyy. Solution, take the cars with the weakest couplers and put them at the end of the train. Notice I said weakest. Owing to manufacturing irregularities, some couplers had knuckles that were slightly less long or accepting pockets too wide. So, some cars stay coupled and some do not even though the knuckles ARE locked.
Problem #2 Droopy Guys
On the new 16 section sleeper, the coupler pocket screw was loose causing the coupler to droop and causing the ******* thumbtack to catch on the stock rail of switches. Result? Derailment every time.
Sooooooo, I took the truck apart, first the roller plate, then the adjustment sections, and then removed the thumbtack plate. Turning the coupler over revealed a screw improperly inserted. So, I rescrewed and cut off the thumbtack. All of this, of course, in addition to adding electrical tape to the bottom of EVERY thumbtack. Fail to do that and a short will occur every time.
Long term prognosis: Replace the couplers on all the offenders, or, run the cars out of proper order, or send the offenders back to Atlas with all the cost and aggravation, or put the two new cars on a shelf and admire how gorgeous they are.
Watch out for the extra hippo.
k, thank you