Big Jim posted:I have no knowledge of these cars, however, if the drawbars (read...couplers) are truck mounted...there is the problem with pushing!
Any truck mounted drawbar in any scale will have this problem because the pushing force is imparted to the truck, not the car body, making it tend to skew (even on a straight line) and thus derail.
If the drawbars/couplers were body mounted the pushing force would not be directly transmitted to the trucks leaving them to rotate in the curve on their own and exponentially reduce the tendency to derail. I learned this many years ago while in HO.
And there, in a few concise words, is a PERFECT explanation of the shoving problem with truck-mounted couplers. Nicely written, Jim.
About the only thing you can do to improve things is to add a little weight to the cars. The NMRA web site has a good recommended practice for car weighting. If you choose to follow it, you will be amazed at how much it improves the tracking ability of your rolling stock.
The NMRA Recommended car weighting standard for O scale cars is this:
- BASIC WEIGHT: 5 ounces
- Add 1 ounce of weight per inch of car body length
- EXAMPLE for a 21" long car (your 86' flats)
Basic Weight: 5 Ounces
Additional Weight: 21 ounces
Total Car Weight = 26 ounces
As built, those cars are MUCH lighter than that.
Given that we 3-railers typically run much tighter curves than the 2-rail scale guys, you could cut that weight specification by adding only a half-ounce per inch of length and still improve things tremendously.
