Scale Speed

    Among model railroaders the term "scale speed" often comes up when
running trains.  In our world of miniature, it is often difficult to
judge whether a train is running at the proper speed to look realistic
in reference to the distance it is traveling.  In many cases, large
scale railroaders still have traces of "Lionelism"  in their systems,
and often run their trains at speeds that would be dangerous in the 1:1
world.  I know that in many garden railroad videos, the trains seem
running extremely fast.  This may be to get as much running on the
layout being taped as possible in the time permitted, but I have often
heard criticism about this from the group watching.   By running your
trains at scale speed you greatly enhance the illusion that your trains
are in fact part of a railroad empire, and not just toys running around
a loop of track.  Measuring scale speed is not "rocket science" and can
be fun and easy.
    What we are looking at is measuring our models traveling in feet per
second and converting it to scale miles per hour.  Two markers need to
be placed by the track that can be easily seen.  These need to be about
10 feet apart minimum in  large scale. You will also need a stopwatch or
a watch with a second hand for your measurements.
    Get your train up to the speed you want to measure, and time how
long it takes the front of the locomotive to go from the first marker to
the second marker.  Take this reading and use it to calculate your
    Calculate your speed in feet per second, by dividing the distance
between your markers by the time in seconds it took for the locomotive
to travel between them.  This gives you a measurement in
real-feet-per-second or rfps.  Multiply this number by the factors
listed in the following table to get-scale-miles-per-hour.

Scale:               1:32             1:29          1:24     1:22.4          1:20.3

rfps-to smph     21.8             19.8          16.4      15.5             13.8

    For a quick check at slow speeds, time how many seconds it takes a
40 foot box car to travel past some fixed marker beside the track.
Divide this into 30 to get scale miles per hour.  For a 50 foot box car
divide the number of seconds into 36.
    This method is similar to how engineers and other railroad personnel
measured train speeds before speedometers were the norm in locomotive
cabs.  Engineers were always timing the interval between mile posts to
calculate their speed.  Station agents and tower operators would in turn
time the passage of box cars to calculate the speed of a train passing
their respective locations.  In this way railroads were run effectively
and on schedule.