Turnout # vs curve radius

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I know there is no such thing as a dumb question. Hopefully not anyway. I've recently joined NMRA and will probably get many of these answers with their standards info. Do the turn-out #'s have a direct relation to curve radius.i.e.. #6 turnout = 24' radius curve? And where would I find these no's Thank You...Mike
 
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grande man

Bonafied Grande Nut
I know there is no such thing as a dumb question. Hopefully not anyway. I've recently joined NMRA and will probably get many of these answers with their standards info. Do the turn-out #'s have a direct relation to curve radius.i.e.. #6 turnout = 24' radius curve? And where would I find these no's Thank You...Mike
The turnout number has to do with a rate of divergence. Higher numbers have shallow (more prototypical) divergence rates. The diverging route is straight on a standard (not curved) turnout, just like the real thing. "Train set" type turnouts usually have a curved diverging route to work with 18" radius curves and a straight main route. Of course, with curved turnouts, both routes curve. All but the "train set" type are prototypical. That's not much of a technical description, but maybe it will help.
 
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JeffShultz

Stay off the tracks!
There actually is one type of switch that has a curve radius - the Atlas Snap Switch has a curved turnout to match their 18" radius curve track. Beyond that... turnouts diverge but do not curve. The larger the number the shallower the divergence of course.
 
The turnout number tells you the angle the two tracks of the turnout are from each other. Take any measure, say an inch. On a #6 turnout, there will be a 1:6 ratio. Six inches from the frog, the two tracks of the switch will be 1 inch apart. On a #8 turnout, eight inches from the frog, the two tracks will be an inch apart.
 




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