Jan 27 2009
What is F Scale?
What is F Scale?
In scale model railroading, Scale is the ratio of full-sized items, such as trains, track, and buildings, compared to the model size. F scale is a fixed 1 to 20.32 ratio (commonly written as “1:20.32″). This means that 1 foot of F scale model equals 20.32 feet in full size. Therefore if you were modeling a box car that was 40 feet long in reality, the F scale model would be approximately 2 feet (2 times 20.32 = 40.64 feet or approximately 40 feet 7.68 inches). This same ratio or scale applies to buildings, track, scenery, people, everything. You can be extremely accurate in using F scale. It is possible to take the exact measurements of an item in the full-sized world and convert it exactly to the appropriate F scale model size. Standard gauge track rails are set 4 feet 8-1/2 inches apart (gauge). Standard gauge track rails can be modeled in F scale using this calculation: 4 feet 8-1/2 inches = 56.5 inches; 56.5 divided by 20.32 = 2.78051181 inches. Therefore, standard gauge track rails should be set 2.78051181 inches apart on your F Scale model railroad.
3 foot narrow gauge track rails are 36 inches apart, in F scale model track the rails should be set 1.77165354 inches apart. You should note that 45 mm, Gauge 1, LGB compatible track rails are set 1.77165354 inches apart.
Yes, that is why F scale exists!!!! The primary purpose of F scale and the choice of the 20.32 scale ratio is to allow scale model railroaders to continue to use 45 mm gauge track for 3 foot narrow gauge and have an exactly compatible standard gauge track to relate to. Modelers seeking exact prototype fidelity will have to take into account the size of rail and relative size of trains, people, buildings, tracks, etc. However it will be possible (and even encouraged) to have off-the shelf guest 3 foot narrow gauge equipment (LGB and its cousins) run in the same scenes and dual gauge track work as F scale standard gauge trains, and track.
F scale standard gauge trains will appear larger than LGB and similar 3 foot narrow gauge trains. They ARE larger. That is because standards gauge trains are generally larger than the 3 foot narrow gauge trains. However, they could be in the same scale (setting aside various manufacturers differences). This means that a model person could go from the engine of a standard gauge engine to the cab of a narrow gauge engine and be the correct, accurate size for both. This applies to buildings and scenery as well. Where a large scale railroad models both 3 foot narrow gauge and standard gauge operations F scale is one of the best ways to go. Since some people in scale railroad models live by the motto that “bigger is better”, they may also get into F scale just because it is bigger. If you especially enjoy detail, super accuracy, and want to run trains outdoors, F scale may be a fun option.
Have fun!
Trainguy
