Steam & Excursion > Are you building track and plan to run at some speeds on curves?

A hundred years ago there were thousands of miles of new railroads being built.  Many miles were built by logging companies to reach new virgin forest.  Lima Locomotive built hundred of Shay and rod locomotives for hundreds of lumber companies.  Their magazine published some interesting shortcut on how to construct the short lived lines.

One short cut I already showed how you can use a 62 foot long chord and by measuring the mid-point off-set inches, will tell you the degrees of that curve as it will be the same, inches vs degrees.

Now, after you built that 3’ gauge line and decide to run with some speed on the curves, you can quickly learn the proper super elevation if you chose a speed you expect to operate, and vary the length of a chord based on that speed and also measure the mid-point off-set.
That distance of the off-set is the amount of higher outer rail should be over the inner-rail, the super elevation.
10 MPH:  chord length 12.5 feet.
15 MPH:  chord length  18.75 feet
20 MPH:  chord length  25.0 feet
25 MPH:  chord length  31.25 feet
30 MPH:  chord length  37.5 feet
The above is only for three foot gage =36”
 
The number and length of chord for Standard Gauge are greater:
10 MPH:  chord length 16.0 feet.
15 MPH:  chord length  24.0 feet
20 MPH:  chord length  32.0 feet
25 MPH:  chord length  40.0 feet
35 MPH:  chord length  48.0 feet  Maximum super elevation is 4”, In the old days with smaller cars, 6" was maximun super elevation. 
You don’t even have to know the actual degree of curvature. This is 110 year old data but will fit todays operations with MCB wheels.
 



Edited 1 time(s). Last edit at 09/19/20 17:02 by PlyWoody.

Naw. I like when we compensate for the curves, get the correct answerer and result is th train speeds up because something is flawed with the calculations.
Dreamer

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