Re: geometry puzzle: frogs in a dualgauge turnouts

Hi Casey,

>unless you are trying to get an award for accurate detail for one specific switch or yard

well, actually that is it

What I've observed for NG turnouts is, that none is close to the standard, yet they have a lot it common. So I've picked a pretty average one (#41 in Chama, i.e. turnout that starts the Y) and made a very precise drawing of it. The article I've written then describes the variances typically seen.

It's on my list to translate the article to English, to make it available for all, if anyone want's to have the German version right now, I can send the PDF.

What I'm doing now, is writing a short second and third part of this article (due in FREMO magazine 3/2010 and 4/2010), covering dual gauge turnouts and stub switches.

For stub switches I've measured the one in Rockwood, of course I can't discuss the variances, because I have not found another one. So I can just hope, this sample is close to the average.

For dualgauge turnouts I can't measure a specific protoype, because there is none. So I can only reconstruct an average turnout with the help of the ex-dualgauge turnouts (La Jara, Alamosa, Antonito D&RGW station), photos and the one in Antonito (CTS station).

My assumption is, that the SG geometry is like in the MoW plan (plan 73.5: #8.5 90lbs with 15' switch and 15'frog) and the curved rail for NG has been bent until it did fit.

What I've observed is, that the ex-dualgauge turnouts don't vary as much as NG turnouts, still the tie layout varies a bit.

My overall goal is to provide a reference, which allows building turnouts/layouts, which look realistic. E.g. for a regular NG #8.5 turnout, 29 ties from headblock till PoF are common, 28 can be seen sometimes, other numbers are rare. So a layout, where all turnouts have, let's say 25 ties (headblock till PoF), is pretty unrealistic wrt. turnouts.

Christian