How fast are your trains going? Many of us think we know, but our perception is all relative. For example, just coming to eye level with a model train will make it appear to be going much faster than if you stare at it from above.
The numbers on the dial of most transformers are also of little help. Different locomotives will perform differently at a given voltage and on most conventional systems, adding additional locomotives will slow down the performance of each as well. DCC systems offer greater control and the ability to program locomotives to operate on a specific speed table. But this is all still different than scale speed in terms of miles or kilometers per hour.
Before we can determine scale speed, first we need to understand scale distance. Although our measurement of time doesn't change (an N scale second is just as long as an O scale second, or a 1:1 scale second,) distance is relative to the scale of the trains.
A scale mile (or kilometer) is determined the same way measurements on your models are made - by dividing by the proportions of your scale. So an O scale mile would be 1/48 of an actual mile. If you want to measure the length of your mainline, here is a list of scale miles and kilometers for the most common scales.
- G Scale*: 240 feet / 45.45 meters
- O Scale: 110 feet / 20.83 meters
- S Scale: 82.5 feet / 15.63 meters
- HO Scale: 60.7 feet / 11.5 meters
- N Scale: 33 feet / 6.25 meters
- Z Scale: 24 feet / 4.55 meters
* There are actually several scales which use a common G Gauge track. The scale varies by manufacturer, but all of these figures are based on a common 1:22 proportion. You may wish to adjust the numbers based on your own particular modeling scale, as can be found in this list.
A Scale Speed Trap
Once you know the distances, you can begin to calculate scale speeds. More important than just knowing the scale speed is being able to measure it.
There are electronic speed recorders that you can buy for your model railroad. A less expensive way is to set up your own speed trap.
By setting two landmarks a known distance apart, and knowing the time it should take a train at a given speed to pass between those two points, you can easily tell how fast the train is going just by counting off the seconds.
The table here will give you those times for all of the major scales in both miles per hour and kilometers per hour. Take note of the distances used to compute these times - for G scale, a distance of 6 feet and 2 meters was used. O through HO scales used one yard and one meter, and N and Z scales have distances of just 1 foot and 1 meter. These changes distances should make it easier to determine speeds in each scale.
On your layout, place two markers at the given distance apart. Telephone poles (paint the base of the designated poles white or provide another distinguishing mark) or other details like mileposts, call boxes, etc. make easy and inconspicuous markers.
Print a small version of the table for your scale and distance and place it on the fascia between the posts and all your operators will be able to keep their speeds in check.
Now all you have to do is set the speed limit!
|MPH||G - 6 ft||O - 3 ft||S - 3 ft||HO - 3 ft||N - 1 ft||Z - 1 ft||KM/H||G - 2 m||O - 1 m||S - 1 m||HO - 1 m||N - 1 m||Z - 1 m|