Now if I think about it... tan(1/9) = 6.34 degress and tan(1/18) + tan(1/18)= 6.36 degrees for those who aren't surveyors. That means the divergence ratio is 1:8.97
Hmmm... 0.2 degrees and .03 sure slices the baloney thin at 3/16" scale. I'm sticking with 1/N where N is the number turnout for my divergence ratio. At 1:1 scale this could become quite serious. Ben Trousdale --- In [email protected], "Gavin" <csowry@...> wrote: > > It is. > > A #9 frog is 6deg 22min 02sec. > A 1 in 9 is 6deg 20min 25sec. > > --- In [email protected], "Gavin" <csowry@> wrote: > > > > ..or is it 2 (tan 1/12 + tan 1/12), must look up the ARA specs. > > > > --- In [email protected], "Gavin" <csowry@> wrote: > > > > > > The British actually use 'straight' frogs, just like in USA, and here in > > > NZ. It is the Germans, and some other European railways that use curved > > > frogs. > > > > > > There is a difference between British/NZ and USA in measuring the frog. > > > The geometric angle of a US #6 frog, say, is not the same as a British 1 > > > in 6 frog. > > > > > > Off the top of my head, the British formula is tan 1/6, whereas the > > > American is 2 tan (1/12 + 1/12). > > > > > > --- In [email protected], "Ed" <Loizeaux@> wrote: > > > > > > > > > Only "toy trains" have a curved frog. > > > > > AbBaird > > > > > > > > As a general statement for American railroading that is true. However, > > > > in England most real turnouts are made with a curved frog. My > > > > NYC-themed layout has almost all curved frogs (and curved adjacent > > > > rails) because I use White Oak Models turnouts sold by Kelvin White who > > > > lived in Oxford at the time. Even though they are technically > > > > incorrect for the NYC and other American railroads, I like them because > > > > the longer continuous curve equates to a much larger "real" radius than > > > > the typical American design with straight points/curved closure > > > > rail/stright frog/curved rail past the frog. Thus, I find it much > > > > easier to ease the 4-8-4 Niagara and other 8-coupled wheeled steamers > > > > through a #6 turnout in the yards. Ken Reiter's SP 2-10-4 also goes > > > > through a #6 turnout of this type easily. Yep, bending the rule once > > > > in a while pays off. Cheers....Ed L. > > > > > > > > > > ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/S-Scale/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/S-Scale/join (Yahoo! ID required) <*> To change settings via email: [email protected] [email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
