The discussion in the thread “Are you cheating on your boxcars?” has prompted me to bring up something I’ve been thinking about for some time - scaling loco power to match the layout.
The concept came from a John Page editorial in Model Railroader from the 1950s.
The idea is to adjust the pulling power of locomotives to fit the train lengths on your layout, while maintaining proportional power levels between units. For example, my BLI Heavy Mikes can pull 16-18 cars (not counting the caboose) on level track (as I’m just about to start on the grades - 1.7% maximum, roughly - I don’t know how they’ll do there yet). They’re about the biggest power I’ll normally have on the layout, which is designed for a maximum train length of about 22 cars. I won’t want the loco to slip pulling the maximum length train, so I’ll add about 10 per cent and adjust the loco to pull 24 cars, either through adding a bit of weight, or replacing the main driver with the traction-tired one that came with the locos. My P2K 0-6-0 yard switchers are about the smallest power on the layout, so I’ll want them to be able to handle a cut of maybe six cars maximum. The 0-8-0s should handle maybe eight cars. Everything else will fall somewhere in between. Consolidations will be weighted to handle perhaps 14-18 cars (depending on whether the locoos are light, medium or heavy). Pacifics, Praries and others will be scaled to handle appropriately shorter trains. If I do add a Santa Fe or a Texas, they will be scaled to handle the very occasional over-length train of 25-27 cars.
If my maximum train length was 30 cars, loco power would be scaled up to handle the longer train lengths. If it was 20 cars, loco power would be scaled down.
This will make the hostler’s job more complex because now he’ll have to fit the loco to the train. If all the big power goes out too early, later trains may not have the locos they need to pull them. If a train goes out with a too-small loco, it may get hung up on a grade a
I like your line of thinking. It’s very sound …and prototypical.
That’s something that can be done to a fairily good degree in HO and larger scales, and sometimes with larger steam in N scale.
I started that post because I have this freakish “thing” for small to medium steam in N scale and theres just not a lot of room to fiddle with those things. The boiler is pretty full from the factory.
I do have a little room in some of my medium sized loco’s though, and I like this idea. I think some experimentation is in order on the Autumns Ridge Railway & Navigation’s rails.
On my old layout (now coming down due to a move) I had 2.5% ruling grades. That grade set the train length. On my 10x25 three level layout, I could run prototypically long trains of 68 cars or so, but trains that long looked silly doing so (they were longer than one side of the layout!). Besides, the only power I had that could handle that large a train was three engine GP9 lashups (and I’m a steam guy, so that option was out!).
My train length solution was simple: figure out how much train my largest engines could drag uphill (P2K 2-8-4s), and set that train length as my passing siding length (plus two cars or so for luck). All of my rolling stock has been tweaked to include free-rolling metal wheelsets and NMRA RP weight. My Berks could handle 22 cars uphill, my USRA light mikes (from various manufacturers) could handle between 12-20 cars, and my 2-8-0s could handle between 8-12 cars (my brass H-5 Mikes could handle 30 cars uphill, and were rejected for the test! We stopped testing my Mantua Mikes at 45 cars).
If I had gotten to the point of operating sessions, I was going to have car cards for each engine, which would tell the engineers and yardmasters how much “tonnage” each engine could handle uphill (downhill was obviously not a problem!). I’ll be implementing this procedure once I get my new 15x25 layout off the ground.
So from my experience, it’s always better to plan the layout around the engines, rather than trying to re-engineer the engines to fit your model of what you believe the engines should be able to handle. Especially with modern plastic steam (which has almost no room for TE improvement) this is a simpler solution. Besides, real railroads did about the same thing, so why not us modelers?
Always a good idea. For those locos that can pull WAY more then they ‘should’, you can set tonnage limits using some formula. Usually the layout size is more of a limiting factor - like in orsonroy’s case, yeah he could run 68 car trains but they looked ridiculous. Even when I get all the way around the basement, it looks like in my space a 15-18 car train will be the max without having it in 2 towns at the same time - I’m still trying to figure out how some of these people squeeze so much into such little space - I still think they ‘cheat’ on the drawings in MR. Anyway, even my smaller swichers can pull 15-20 cars - so I will have to artificially limit the train length a given loco can pull. Now, all but the greenest operator is goignt o realize that they cna tack more cars on than the tonnage charts say - so you just have to do what it takes to keep your yardmasters honest. You see a few too many cars in a train - pull the old “owner’s privilege” card and say it’s now derailed - or somethign that will cause enough of a headache for the offending yardmaster that they won’t cheat anymore. [:D]
Ah, but there’s nothing like having a too-small loco ineefectually slipping its drivers on a ruling grade to bring home tonnage limits!
Just SAYING that a loco that can handle 50 cars can only 22 isn’t at all the same thing as the loco really being able to handle only 22 cars - at least in my opinion.
This is true - but uless we are prepared to deface our locos and mill out weights and so forth to make them TRULY pull less, there’s not much we can do but fake it and play by the rules.
It’s easier to do it for real with steam - most model steam engines aren’t even properly balanced to get the most from what pulling power they have.
Unfortunately, I model the mid-50’s, so pretty much all diesel. Every single one of my locos will pull more NMRA-weighted cars than the prototype could, unless I add obscene amounts of weight to the cars, or use 4% grades. Even if my loco could only move a realistic 20 cars, I guess I’d never need multiple units, as I don;t have the space to run more than 15-20 car trains - so once again there is the need for an artificial limit. 15 cars plus caboose with 2 units pulling doesn’t look odd to me, even though the prototype loco could easily pull those 15 by itself.