Fast Tracks

I'm just about to embark on my first N gauge layout and was wondering about turnout sizes.
What considerations are there when selecting a particular size?
I realise that space and prototypical accuracy may dictate a certain size, but operationally is a size 6 turnout better or worse than say a size 8?
Should the smaller sizes be avoided in any particular scale?

Keith
Tasmania

keith,
the number of a TO is basically a ratio indicating the how "sharp" it is.
the lower the number, the sharper the turn.
for example,
a number 6 TO...takes 6 units of distance to deviate 1 unit...
and a number 8 TO....takes 8 units of distance to deviate the same 1 unit...
so, operationally, many prefer to use as high a number as possible.
this ensures smoother running through the TO's.
this is especially true for mainlines where speeds would be higher.
also, it is more prototypical

Hello Kieth,

We in the model field have always been used to turnouts on the small size (like number 4's or 6's.) reality is number 10' or 12's should be used for mainline use (50's period) with the smaller turnouts used only for industrial/yard trackage. Longer crossover type turnouts could be used for high speed heavy duty mainline crossovers (sizes 14 up to 20 frog)

One of the UP yards in the west had or may still have numbe 10's in the yard that they had their biggest steamers (articulateds included)

Larger is better, smoother, more realistic looking.


rob

I agree that the larger size you can use is best. However, there are some places where you may have to sacrifice, unless you have unlimited space.

I will use only #8's or larger for the mainline, strategically placed to keep the quantity as low as possible. Passing sidings and passenger stations will be mostly #6's with a few #8's. Yards will be #5's and #6's, with a few #8's. Industrial sidings will be #5's and #6's, with #4's and #8's used sparingly (only where it would look appropriate and railcars plus some switcher loco's could negotiate the #4's). If I did have unlimited space, the smallest would be #8's. Although I do not think real railroads used curved TO's very much, I will use them in several locations.

Each RR modeler has to suit themselves first, if it works for you, do it!

No one has unlimited space, but truthfully, I would rather have a siding a car or two shorter with larger turnouts Entering and departing. On passenger yards or crossovers this is more important. Number 4's 5's for industrial, number 6 and 8's for yards. 8's or 10's on the main, with an occas number 12. here and there.

Rob