turnouts and radius

[dtbarron]

question, if I want to use Peco Turnouts number 6 and 8, is there a set radius for that or can I make whatever Radius I like,   say 28, or 30 or 32.. also if I use Atlas flex code 83 on main lines, is it ok or even a good idea to use code 100 in Tunnels and in my Helix?? thanks for the help

[IRONROOSTER]

You need to lay all track carefully.  If done correctly, code 83 should work as well as code 100.  Older trains had deeper flanges which required code 100, as long as you aren't running those you should be okay.  If you do change codes make sure the transition is smooth.

I'm not familiar with Peco turnouts.

Good luck

Paul

[rrinker]

 The chart here: http://www.nmra.org/standards/sandrp/rp12_3.html

has all the info. The Peco #6 and #8 Code 83 turnouts are built to NMRA standards. There are two points to note. One is line number 11 in those charts, the closure rail radius. This is the sharpest curve in the turnout, and is usually the deciding factor on how large a locomotive can actually negotiate the turnout. For a #6, it's 43", for a #8, it's 67" - basically any size loco can negoiate either size. The other radius is the substitution radius, which is the equivalent radius that the turnout repalces - more or less, since a proper turnout has straight parts in it and it's not an exact fir, such that you could cut out a chunk of a curve of that radius and just drop in the curved leg of a turnout. That is line 6 on the chart. For a #6, it's 56", for a #8, it's 110" (the chart is wrong - or referring to a different number). This is why John Armstrong recommended nothing more than a #6 unless you have a cosmetic reason to use a larger turnout, as a #8 or bigger takes up a LOT of space. Crossovers are another palce to use the bigger turnout, to lessen the S curve effect.

                   --Randy

 

[Texas Zepher]

dtbarron

question, if I want to use Peco Turnouts number 6 and 8, is there a set radius for that or can I make whatever Radius I like,   say 28, or 30 or 32.

Yes as Randy pointed out with the reference, but it is much better to make two separate radius.  Make two separate curves, one from either side of the turnout rather than trying to make it "fit" into the curve.    On the other hand I believe Peco makes some curved turnouts.  54" outside and 48" inside I think.

also if I use Atlas flex code 83 on main lines, is it ok or even a good idea to use code 100 in Tunnels and in my Helix??

Well I don't know if it is a good idea or not, or even what you really mean by that.  The trains aren't going to run any better on one over the other.     Each time you switch rail size there will have to be a transition.   So I guess if you are good at making the transitions so there isn't a bump for operational considerations go for it.

[tomikawaTT]

To answer your second question first, if you already have code 83 and would have to buy code 100 - don't bother.  As long as you lay your Atlas track with appropriate care, there is nothing to gain by going to the taller rail.

I personally have Code 100 hidden track, for two reasons:

1. I already owned a couple of scale miles of code 100 flex from earlier layouts (various brands including bought-in-Japan Shinohara and some brass rail on plastic ties made in Italy.)
2. Code 100 was cheaper than code 83 when bought on sale when I laid in my supplies.  That may no longer be the case.

However, deep in the Netherworld, on one route which will be used by every train which has a locomotive at one end, there is one test section of Atlas code 83 flex - installed there to verify that the joints would come out level.  It's joined to the code 100 on either side by Atlas 'Universal' rail joiners, with the code 83 ties cut way down to let them sit level.  Fancy transition sections and/or transition joiners are NOT necessary between the two sizes of rail.

As for Peco turnouts (or any other store-boughten specialwork) I can't help.  I hand-lay all of mine.

Chuck (Modeling Central Japan in September, 1964)