To keep some custom rolling stock on the rails I have to add weight, how much? To any book learning dudes what would be the scale weight of a prototypical engine that weighs 40,000lbs, at our linear 1:160? thanks, thad
Oh, no... you didn't go there. Weight doesn't scale the way most people think. Weight is directly proportional to density, which depends on volume... So the weight of a 1:160 (linear) scale object is 1: (160*160*160) == 1:4,096,000 Your 40,000 pound engine - that's an awfully small engine, btw... a switcher? - would weigh only 0.16 oz. Actual N scale rollingstock is much heavier than "scale weight" for operational reasons. A true scale weight car (or loco) would have trouble staying on the rails. NMRA has a a recommended practice for weight of rolling stock... it's dependent upon the length of the car. For N scale it's 0.5oz + (0.15 oz * length of car in inches). A 50 foot boxcar should weigh about 1 oz. You'll find a rather humorous treatment of this topic (and learn why I have a rather notorious reputation for dubious physics) in this thread on nScale.net.
Adding more weight is only part of the problem. Additional weight will not fix bad track work. So it is very beneficial to pay attention to the basics. One point with car weight is consistency. Not only will different manufacturer cars weigh differently but their rolling capacity may also differ. Trying to get cars to weigh the same and settling on one truck and wheelset combination [in addition to good track] will help a lot. The NMRA guides to car weight is a good start and the industry defacto standard of the MTL truck/wheelset combination really helps.