Hi everyone, finally getting back into model railroading and have some questions. I working on a layout L-shaped, 8 x 4 with a 4 x 4 leg. I want to run 22" radius turns due to my engines having 6-axles. I trying to lay things out with the freeware from Atlas and I’m having problems with the 22" radius turns and #6 turnouts. My question is if I add a #6 turnout in a curve what do I need to add to the turnout to continue the 22"? I’m trying to run a mainline around the entire L-shape then on the 8x4 section is have a oval on that with some sidings. Thanks for the help in advance.
P.S. I’m modeling Union Pacific with some Southern Pacific locomotives.
You’re having trouble because the no. 6 turnout doesn’t fit conveniently into a 22-inch radius curve. The “substitution radius” for an HO scale no. 6, the curve you could replace with the curved side of the turnout, is 56 inches. To cut a no. 6 turnout into a 22-inch radius curve, your track plan has to allow for a turnout-length segment of the larger radius with arcs of the basic radius to either side. See the Kalmbach book, “Track Planning for Realistic Operation,” by John Armstrong, for illustrations of this geometry.
Some manufacturers make curved turnouts that have through routes that are not straight, but curved. They come in several radii, so you may be able to find one that works. I have used the Shinohara #7.5, although their curved diverging route radii are considerably smaller than advertised in some cases. The #7.5 is, unfortunately, one of them.
I will look around and see if I can post a link, or perhaps someone will have it more quickly.
You should know that a person in another forum reported that he had trouble with 6-axle diesels getting through the Peco turnouts. I am not aware, at this point, that Shinohara makes one tight enough for 22" curves, but I’ll find out.
At Walthers, it doesn’t look as if Shinohara makes a 22" outer radius, only 20".
There was an earlier thread specifically about Walthers/Shinohara turnouts to which I posted this:
"To recheck my curved turnout sizes (Walthers/Shinohara Code 83), I built a homemade beam compass, laid-out arcs and overlaid the turnouts. The results are:
• #6/#6.5: 24/18 (frog# depends on whether you believe the box label or the imprint on the turnout!)
• #7: 28/22
• #7.5: 32/26
• #8: 36/30
I also checked a #4 Code 70: with a 22" radius for the closure rail, it must actually be a #4.5.
The inside radii are not what Walthers posts nor are they as imprinted on the underside of the turnouts!"