Can someone explain or point me in the direction of an explanation as to what the two numbers on an atlas switch mean. I'm looking at item #6078, which is a 072/054 right hand curved switch. I'm not sure I understand the two dimensions.
And while we are at it what is the difference between a turnout and switch?
Thanks
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072 is the outer curve diameter and 54 is the inside curve diameter
John Graser posted:072 is the outer curve diameter and 54 is the inside curve diameter
That makes sense. Other than a space issue why would I need to know the inside diameter. When a car or engine is rated for a specific curve dimension its based on the outside diameter correct?
Bossman: What John was alluding to was that the outer branch of that turnout has track that duplicates an 0-72 curve, while the inner/turnout branch of track follows a 0-54 curve. That means the direction of the "turning out' part of the turnout will be a sharper turn of track than the outer 0-72 branch of track exiting the turnout.
As far as terminology, "turnout" would be my preferred word to use for tracks that diverge from a single line. A "switch" is a better term for a device that controls electrical circuits.
Bossman284 posted:John Graser posted:072 is the outer curve diameter and 54 is the inside curve diameter
That makes sense. Other than a space issue why would I need to know the inside diameter. When a car or engine is rated for a specific curve dimension its based on the outside diameter correct?
Engine/car ratings are exclusive of a double curve switch. The curve rating is the minimum recommended curve diameter....period. Ergo, for example, if your engine were rated at O72 minimum, and you had the aforementioned O72/O54 switch on your layout, you might be restricted to using the outer curve, only, for operation of that engine. If someone tried running it through on the O54 curve, they might experience problems...derailment, etc..
Turnout vs. Switch?......I believe turnout is technically the correct term. OTOH, both terms are used extensively ...in this country, at least....without a lot of gnashing of teeth, lashes with a wet noodle, or grammatical challenges. (Of course, there ARE some who frequent forums who can't resist refining our use of the Americanized Queen's English!...stay tuned!!)
KD
D&H 65 posted:Bossman: What John was alluding to was that the outer branch of that turnout has track that duplicates an 0-72 curve, while the inner/turnout branch of track follows a 0-54 curve. That means the direction of the "turning out' part of the turnout will be a sharper turn of track than the outer 0-72 branch of track exiting the turnout.
As far as terminology, "turnout" would be my preferred word to use for tracks that diverge from a single line. A "switch" is a better term for a device that controls electrical circuits.
D&H65 Ok I understand what you are saying but I'm not sure I'm any clearer! So for instance if I have a piece of rolling stock that requires a 72" curve am i looking for a 072/072 turn out?
And what is it when they refer to a #6 or #8 turnout.
Sorry for all the stupid questions today!
Ok guys....it all kind of just clicked and I get it now! Thanks
The 072 and 054 should be able to fit right in when using sectional track.
Rod Miller
#6 or #8 turnout is the number of degree (angle) of the frog on the switch. The large the number the more gradual the switch.
If it helps at all, on an 072/054 switch there is no straight leg. Both parts are curved, they just curve at different radii is all.
As I understand it, a #6 turnout requires a distance of 6 x the track width to separate one track width from the mainline; a #8 requires 8 x the width, etc. In other words a #6 turnout is sharper than a #8.
The Ross Custom Switch website has pictures of all these and more, just for reference
Rod
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