The diverging leg of the turnout doesn't branch off straight - it is curved at an 18" radius.

Are you asking what it takes to get the diverging leg to become parallel with the straight through portion like if you were to create a siding?

 

Ok, the diverging radius is 18 inches. How many degrees is the diverging 18” radius?

 

If it is a snap switch, there are actually 2 versions of it. They both come off as an 18 inch radius curve. One is at 20 degrees and one is at 15 degrees. One uses a 1/3 18"radius piece of track to complete the curve the other uses a 1/2 18: radius section of track to complete the curve. I forget which is the 15 degree and which is the 20 degree. The most common one is the one that takes the 1/3 section of track to complete the curve.

 

The Atlas snap switch has a 18" radius and 20-degree angle on the diverging route. There may have been some Snap-switches with a 15-degree divergence. As was already mentioned by Dave.

 

Turnoff

Thank you all for the information, very helpful.

 

Turnout angle



Billgeyer;

The turnout you have is something of an exception to the normal rule in terms of angle of divergence. Most model, and full-sized, turnouts don't have a curved route at all. Instead there are two straight routes that diverge (aka split from each other) at an angle. The normal means of expressing the sharpness of this divergence isn't the geometry system of degrees of angle, but a system called frog number.
I'm guessing that the amount that the straight route of your Atlas snap track turnout splits off from the 18" radius curve is what you are trying to find out. Is that correct? If so, the easy way to find out the actual degrees of angle involved would be to use a protractor to measure the angle between the straight and curved route's rails right near the frog.
The frog number system, commonly used to describe turnouts is based on the number of units of sideways divergence that take place in a given distance of forward travel. If a wheel travels six mm. forward to get one mm. of sideways divergence then the frog # is six, and that is a #6 turnout. You may see ads describing a turnout as either a #4 or #6 or #8. These are frog numbers. The lower the frog number the sharper the divergence of one route from the other. Your Atlas "Snap switch" doesn't really use this frog# business, since it is made to fit in place of an 18" radius curved section of track. Other Atlas, like many of their "custom line" turnouts, and other brands like Walthers/Shinohara, and Micro Engineering, turnouts do use the frog# system. I know it's confusing for a newbie. I'm attaching some pdf files that may help explain things.

good luck;

Traction Fan:smilie_daumenpos:

View attachment Improving Atlas turnouts pdf version.pdf

View attachment Where do I start (revised version).pdf

View attachment Model Railroad Terminology 2.1.pdf

View attachment MODEL RAILROADING ON A BUDGET.pdf

 

And, as is now obvious, what you call a "turnoff" is in reality called a "turnout".....