laying curve track to lean

UPJ,
The leaning you're refering to is called super-elevation. There have been several threads about it. You might try searching thru past posts. Basically you add something under the outside track to create up to about a 4-5% cross slope on the tracks, typically throughout the curve. You should also ease the outer rail up and back down. I've heard about guys using several layers of tape, thin cardboard, stryene, cardstock, etc.
DOc
 
babydot94513 said:
Silly question, but why make the rail lean in the first place?

JD
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JD, The "lean" is to keep the load even on both rails in a high speed turn. Like a banked turn on a race track. On a flat curve the weight would shift to the outside rail, and a passenger would be pulled that way also.
 
OK - I get the overall concept of "the lean" but realistically does it really matter on an HO scale application?

SAL Comet said:
JD, The "lean" is to keep the load even on both rails in a high speed turn. Like a banked turn on a race track. On a flat curve the weight would shift to the outside rail, and a passenger would be pulled that way also.
Click to expand...
 
It's all in the center of gravity. If you have a good sense of it then it shouldn't be to hard to do. Just a little concentration. But keep in mind that when your building it to "bank" there are cars that are short, long, tall, short, as well as light and heavy. These are key things to think about when you lay it down so you'll know when it's to much of a bank or not enough.
 
The best rule of thumb I can offer is; if you're running steam era 40' cars, superelevate. If you are running modern, tall, high capacity cars ( 89' auto parts boxcars, auto racks, double stacks) don't superelevate.
I know it looks great, but the modern cars will tend to fall into the curve, and superelevation ( enough to be visible ) will increase that tendancy. Remember, model trains do not have the same physical "moments"( distribution of weight, center of gravity, reaction to centrifugal force ) as the prototype cars, and react much diferently to superelevated curves.
Pete
 
thanks guys this will help me alot. My layout is going to be Logging and Coal runs on a point - to - point layout.

One thing is did they super elevation on logging mainlines back in the days :confused:
 
UPJunkie said:
thanks guys this will help me alot. My layout is going to be Logging and Coal runs on a point - to - point layout.

One thing is did they super elevation on logging mainlines back in the days :confused:
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I think the term "logging mainlines" may be an oxymoron. Logging lines were generally backwoods operations with temporary track put down to get trains into the woods where they could be loaded with logs and then to get them to the sawmill where the logs could be sawed into lumber. The first time that log saw anything resembling a class 1 railroad was when it was a lumber load on the train headed for a big city lumber yard!
 
Superelevation is a function of curve radius, train speed and train type. (Can you tell I'm a math grad?) If the prototype were running on our curves at our sppeds, it would be banked like a race track at about 45 degrees.
As a passenger, banked curves are very nice at speed, but if you stop on them there's a funny sensation of sliding down your seat to the center of the curve -- opposite to the feeling of going around too fast. It does interesting things to your coffee cup. The Brits refer to "cant deficiency" which is how much more tilt would be required to keep the coffee level.
In HO, a reasonable amount can be made with 2 or 3 layers of making tape under the outside rail. Remember to build it up slowly over a passenger car length or two.
 
UPJunkie said:
thanks guys this will help me alot. My layout is going to be Logging and Coal runs on a point - to - point layout.

One thing is did they super elevation on logging mainlines back in the days :confused:
Click to expand...

Nobody has answered this question: Logging lines would not superelevate the curves. Superelevation is a costly feature to construct and maintain, and with the temporary (and low speed) lines the loggers used, they wouldn't care.

Superelevation is found on high speed (< 25 MPH or so) track, usually, but there will always be exceptions for and against it.
 
UPJunkie, there is an article in MR July 2004 How to lay track perfectly that briefly covers how to super elevate track. The author states that he places a .040" styrene shim under every 15th tie to raise the track. He starts out with a .010" shim and then increases the thickness of the shims by .010" until he reaches the desired height. Then he uses the ballast to fill in the remaining space under the ties. Hope this helps.

Freelancer
 
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