Gary S. said:
I think the heavier cars will help in all aspects of coupling and uncoupling. However, I have one negative to report. To get the 12 car train moving, I had to crank the throttle up pretty good to get the train to move, and as soon as it would start rolling, it would kinda lurch up to speed, as in the friction would go down as soon as the initial drag of the train was overcome. I'm not real happy about this. Now I understand why free-rolling cars are desirable. It allows the loco to creep up to speed from a stand-still, and to pull a train very very slowly without stalling. It is my opinion that the loco manufacturers need to change the gear ratios in the locomotives, cutting the top speed about in half, which would give much more low end power and speed control.
I've found that the main disadvantage to heavier cars is their effect on loco performance when a grade is encountered. However, I feel that operation can be enhanced with heavier cars if operating practices are modified. Starting a reasonably long train with normally weighted, free-rolling cars can often result in false uncouplings as the train passes over a track magnet. If the loco stutters, even momentarily, on a turnout, or slight undulations in the track cause the free-rolling cars to bunch up due to slack run-in, couplers over the magnet can part. Part of the key to starting a heavy train is to follow prototype practices, and "take slack" (back the loco into the train to bunch the coupler slack - coupler slack on our model trains is proportionally greater than on the prototype, by the way). When the loco starts to move forward, very slowly, the weight of each car is added individually to the load, and this should occur throughout the length of the train, with no sudden increase in speed. This requires both smooth-running locos and a control system that offers power with control. My normal power source is an MRC ControlMaster 20, with a walk-around controller. This power source will power pretty much any or all of my locos, including multiple locos on heavy trains. However, the controller, in my opinion, is a bit heavy-handed, and very touchy to speed adjustments. On a very heavy train, this is not a problem, as the weight of the train tends to smooth things out. On a shorter train of heavy cars, or a longer train with a mix of light and heavy cars, this does present a problem, as the lighter cars respond more quickly to throttle adjustments. Slack run-out and run-in can occur at the same time in different parts of the train, even on level track. Passing over an uncoupling magnet usually yields interesting results.

If I need to mix light and heavy cars (well under or over recommended weights), I try to place the lighter cars at the rear of the train, where this unpredictable slack action will have little effect on the rest of the train. This also makes the chance of "stringlining" on curves less likely.
Changes in grade, both up and down, introduce slack action into the train, and again, with heavy cars and careful operation, train handling can be done quite prototypically.
The introduction of helper locos on the rear of a train will necessitate even more careful operation, but if car weights are fairly consistent for the entire train, it can be interesting to watch the point of neutral slack move through the train dependent on which end of the train is on a grade, either up or down. Introducing a lighter than normal car into a train with motive power on both ends is asking for trouble.:curse:
I also have two different types of SCR throttles, which run from an AC power source. These offer excellent speed control (one even has a mutiple-position brake, which allows the operator to set the speed, then control the train with the brake), but unfortunately, these will not put out enough power to run multiple locos on a heavy train, especially when a grade is encountered.
I have a friend whose philosophy is to add weight until the trains will stay on the track,

and, having operated on his layout several times, almost always derailment-free, I can see some merit to this idea. I once scratchbuilt a boxcar for him, and knowing his methods, weighted it to about 7 oz.: it wasn't the heaviest freight car on his layout, but at least it wasn't the lightest.

He preferred his passenger cars the same, giving true meaning to the term "heavyweight": most were between 10 and 15 ounces, with the majority at about 12 or 13 oz. I weighted some of my own passenger equipment to these same standards, which makes for a very solid-rolling train, but later brought them back to more conventional weights when I occurred to me that trucks with plastic sideframes would eventually experience premature "bearing failure". Most of his cars had all-metal trucks. It was a very impressive sight, knowing the nature of the rolling stock, to see several passenger trains (and a few freights, too) running off the miles, derailment-free, with 5 or 6 locos on the headend, trailing 15 or 20, or even more, Pullmans, or an equally long freight. Operations here were strictly running trains though, with no grades, and multiple track continuous running.
Wayne