Newbie question about turnout numbers

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Hello All, this looks like a good place to play.

I am in the planning stages and have a question about turnouts.

When designing a track plan are there specific reasons (prototypically) that one would use #4, $6, #8 etc turnouts?

Or would different turnout #s be used in a yard vs. a mainline?




Active Member
only reason is dimension. higher number offer less curved diverging path and as such takes more space but allows greater sppeds . on the main line you probably will want to use the highest number you can fit. yards generally can get away with #4 due to lower speeds.


Loveably weird
If you have 6 axle diesels or large steam engines, I wouldn't recommend going below a #6 anywhere that engine will travel. Your yard tracks and industry spurs can use #4's due to shorter wheelbases and lower speeds.
In simplified terms, the number refers to the amount of forward travel, in inches, that a train must go along the diverging rails of a turnout in order to get one inch separation away from the straight rails.
Turnout usage

Thanks Tankist and Flyboy

That definatly helps.

I am still in the very beginning stages of planning my layout and want to
learn as much as possible before I start

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