The prototype can pull 100 cars. There's no reason yours shouldn't either. (Given it's properly weighted or with traction tires or bullfrog snot)I worked out a formula a long time ago where I figured out the exact number of cars you SHOULD be able to pull given the total weight of each car + # of cars and the maximum grade
It came out something like pulling power = (Engine Weight * .8 * cosine(hill angle)) = (total car weight * sine(hill angle) + Sum(axel rolling friction * # Axels * cos(hill angle))) *rolling axel friction is typically around <2% of the car weight for free rolling axels.At a 2% grade you get about half your pulling power due to th eweight of fthe rolling stock pulling on the engine (gravity kicking in on a hill)
Don - Specializing in layout DC->DCC conversions
Modeling C&O transition era and steel industries There's Nothing Like Big Steam!
Thanks to all for teh Posts. Really helpful. Need to change some trucks and check weights!
Gary
Of course it "all depends"............ What is the size of the layout? What RR, era, location is being modeled? What locos do you have available? Do you care if it is prototypically correct or not?
I've got an 11x15 HO layout with lower level staging and storage. Typically there are about 20 passenger cars and perhaps 130 freight cars. All are prototypical length for the 1950s. Without apology, I often run trains way too long for the layout - such as 10 car passenger trains and 20 car freights. Power is ATSF F, GP, RSD diesels and 2-10-2, 2-8-0, and 4-8-4 steamers.
Oh, I've got another 200 or so cars on the shelf, some of which have never been on track.
ENJOY !
Mobilman44
Living in southeast Texas, formerly modeling the "postwar" Santa Fe and Illinois Central
My prototype ran (maximum) 20 car freights, and either doubleheaded 2-8-2s or took a pusher up the 2.5% grade between (prototype names) Agematsu and Kiso-Fukushima. I built my layout to allow the same - passing track length, yard arrival track length, layover track length(s) in hidden staging...
The key is, I'm working from a master plan that's in its fiftieth anniversary year, building my 'last in this lifetime' layout and have long since figured out how to simulate the entire month of September, 1964, in a very limited area of the Central Japan Alps.
That said, my work with a narrow gauge prototype (in an oddball scale, 1:80) on the far side of a rather wide ocean probably has very little relevance to a typical North American model railroader. My recommendation is to decide what YOU (the cat in your boots) want - and then design your layout to suit. For assistance, find and read a copy of John Armstrong's Track Planning for Realistic Operation. It has proven to be invaluable when the, "How do I do this?" questions arise.
Chuck (Modeling Central Japan in September, 1964 - using John Armstrong's methods)
I have a long 2% grade on my layout. This video has three trains on it and each climbs that hill with no problems.
https://www.youtube.com/watch?v=X7Tn4PrzlFI&list=PL5E7C9C3E53977DF4
Brent
"All of the world's problems are the result of the difference between how we think and how the world works."
It all depends on the make up and configuration of your track. Put a loco on the track, and experiment. Hook up cars until it won't pull it any more, or the train "string lines" on a curve, and tips over. That will give you a good idea on how many cars you can pull on your lay out. Be sure to check the weight of the cars, bring them up to the proper weight. The cars will actually handle better, the closer to the recomended NMRA weight of "1 oz., plus 1/2 oz per inch of length" I believe is the formula. Tuned trucks and metal wheel sets make a huge difference.
Mike.
My You Tube
My average train is arround 10 cars but I have a very long dogbone and one day will pull over 100 as my mainline is 180' aprox.
I know it's not realistic to run 100 car freight trains on a Model Railroad but how many should I be able to pull with 1, 2 or 3 locos?