Hello everyone. This is my first post here and I hope some of you can help me out. I am in the extremely early process of planning an N Scale shelf layout consisting of 2-3 levels and I am wondering what is a prototypical radius for main line turns? I plan on using either Atlas Code 55 or Micro-Engineering Code 55 track. Any thoughts or questions please feel free to respond!
Brian
Welcome aboard, Bryan.
Hold onto your chair! A true, prototype radius for North American Class 1 mainline track, even in N scale, would have a radius measured in yards, not inches. Or it could be as little as eight inches if you're modeling the 30 meter radius curves of the Hakone Tozan Tetsudo* in 1:160 scale.
A more realistic question would be, "How great a radius can I fit into my space without losing any of my other druthers?" The usual answer, if you're going to be running full-length Pullmans, auto racks or humonguboxes is, "As wide as you can go."
Another, more practical, way to attack the question is to lay a test spiral and run your rolling stock into it, alone and coupled in any possible combination. Note the, `No go,' radii, then design for a minimum larger than the greatest , `No go' - or plan to embargo certain combos from any curves with smaller radii. In my own modeling, I discovered that building curves that would allow me to couple an auto rack and a four wheel wagon together would require a much larger radius than I wanted to devote to the mainline - so I just don't do that. There will always be an intermediate-length car between.
Note that an ounce of real-world experimentation trumps ten tons of, `Standards' and opinions.
* The Hakone Tozan Tetsudo is a rural electric line south of Fujisan in Japan. I think they established the route by chasing a mountain goat up the pass - in addition to those 100 foot radius curves it has switchbacks, hard rock tunnels and an 8% ruling grade!
Chuck (Modleing Central Japan in September, 1964)
Welcome to the forums.
What era are you thinking of modeling and what length cars do you want to run? As above, the wider the radius you can use the better they will look. It seems to me that I have seen for longer cars and large engines in N, you want to think no smaller than 12", larger if you can get it. Nice thing about flex track is that you don't have to stick to a standard radius.
As you start to progress in your planning, you will have more questions. Come on back and ask away, no question is a dumb question if you don''t know the answer. You can go to the right hand column and scroll down to Search our Community, set it for all forums (sorry, can't remember the exact wording) and you can find posts on your subject. Asking a question that has been asked before is OK, as some people may not have seen it before, others that answered it may know more or have thought of something they can add, we can all benefit. New ideas and different ways to do things turn up daily.
When you do ask a question, give as much information as you can, so that the folks answering can give you the "best" answer for your specific question.
Good luck,
Richard
Thanks for your input so far! I'm sorry I didn't mention the era, locomotive types, and rolling stock.
I want to model the present day era. In doing so I hope to be running a few SD70ACes and an SD80MAC or two. Those would be the biggest locomotives I would be running.
In terms of rolling stock, I would like to run trains of autoracks, trailer trains, and unit trash trains with the new Atlas trash trailers and containers. Of course I would have other freight running too but those would be the longest.
Sincerely,
NMRA Recommended Practice (minimums)
http://www.nmra.org/standards/sandrp/rp-11.html
I tried to sell my two cents worth, but no one would give me a plug nickel for it.
I don't have a leg to stand on.
Prototypical?
A 6 degree curve is 955 ft radius, that's 5' 11 in radius or 71" radius in N scale.
Dave H. Painted side goes up. My website : wnbranch.com
Maybe a more practical answer to the OP´s question.
The absolute minimum radius should not be below 9 3/4", better go for 11".
hi,
some older standards, the ratio between your longest piece of equipment and the minimum radius:
1:2 is called pushing against technical possibilities
1:3 is a merely accepted compromise
1:4 needed for looking good
1:5 needed for merely hands-free (un)coupling.
Especially in N-scale staying close to the 1:3 ratio seems possible.
BTW the kind of railroad you model, the era and location are important for the minimum radius as well. On an older (sub)urban switching layout layout a 1:2,5 ratio with 40 and 50 ft cars is quite possible. Within towns or mountainous areas space is often tight, resulting in smaller radii. Quite different from rural areas in flat-lands.
With the radius you also have to consider turnout angles.
When running long modern freight, up to 90 ft, the NMRA tables indicate a 21" radius and #7 or #10 switches in N-scale. A wee bit better then the 1:3 ratio.
In the end it is up to you, you have to develop your set of standards.
Paul
bbobes327 I hope to be running a few SD70ACes and an SD80MAC or two. I would like to run trains of autoracks, trailer trains, and unit trash trains with the new Atlas trash trailers and containers.
I hope to be running a few SD70ACes and an SD80MAC or two.
I would like to run trains of autoracks, trailer trains, and unit trash trains with the new Atlas trash trailers and containers.
The earlier advice of no less than 11" minimum radius is sound. Refer to Spookshow's N Scale Trainstuff (Homepage) where he talks candidly about minimum radius pros & cons in his half-dozen layouts.
Ask yourself -- "What radius will fit into my actual layout?" -- Take into account an inexpensive & visual radius test...
Draw various radius arcs on a larger piece of cardboard, place one of your engines (and rolling stock) on the radius center, and look down upon the amount of overhang on each radius. Larger radius = Lower overhangs = Better appearance.
Conemaugh Road & Traction circa 1956
bbobes327 .....I am in the extremely early process of planning an N Scale shelf layout consisting of 2-3 levels and I am wondering what is a prototypical radius for main line turns? .....
.....I am in the extremely early process of planning an N Scale shelf layout consisting of 2-3 levels and I am wondering what is a prototypical radius for main line turns? .....
How wide are you going to make the shelves, and do you actually need any curves? My impression of a shelf-type layout is that it's usually point-to-point, and even if the shelves turn at the corners of the room, you can use much wider curves - 30" radius or greater. The fact that you'll be viewing the trains from the inside of the curve will make them look even better.
Wayne
My main line minimum is 15", and that's limited to hidden trackage. Out in view, I try to hold to no less than 18".
Bear in mind that I'm using mostly 4 axle diesels, my largest is an SD40 with 6 axles. The long wheelbase units you're using are going to require a little more thoughtful consideration. While the trucks may swivel enough to fit on 11" curves, your body mounted couplers may be at the outer limits of their functionality at that radius.
Also, consider the rolling stock you'll be using. Modern cars like auto racks can be enormous, double stacks can be very tall.... all of this will factor in where you will be transitioning between levels. If you're using a helix, the decks will have to be far enough apart to clear such beasties, and the radius broad enough to prevent derailments.
I'd start with 18" as a minimum given your druthers...
Lee
Route of the Alpha Jets www.wmrywesternlines.net
Do not go under 11", ever. I model N scale around 1995 or so and I have some large 6 axle engines and some long well cars since I started the layout.
I started with 4 axle engines and 40" and 50" cars. I had a lot of 9 3/4 curves and had to tear most of them out and replace with 11" and larger to run all of the longer stuff. Only in some yards and industrial tracks where only 4 axle engines and 50" or so cars go is there any under 11" left.
It was not fun to tear up the trackage, but I have a much better operation layout and a better track plan. Oh, and a lot more fun.
If I ever do a new track plan I will do as Lee and plan to have 15" and larger as much as possible. The minimum even in yards will be 11".
Ken G Price My N-Scale Layout
Digitrax Super Empire Builder Radio System. South Valley Texas Railroad. SVTRR
N-Scale out west. 1996-1998 or so! UP, SP, Missouri Pacific, C&NW.
I seem to think anything from 18" + would work in this case. However, I need to go back and see how big the shelves might be.
Any ideas on what the length of the shelves should be?
I was thinking about having somewhat long shelves ( 2 ft, 3-3.5 ft max maybe) but I feel I would need to support the shelves on both sides. Any thoughts?
You've all been a real help so far. Thanks!!
Sir MadogThe absolute minimum radius should not be below 9 3/4", better go for 11".
That's about half enough.
NMRA RP-11 says 21.5" radius for those autoracks. That also fits with the 1:3 ROT. Some have pointed out smaller can work, but it looks kinda silly when you look down on top of a car and see rail curving out from under it. You are of course free to ignore how it looks.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
I have 15" curve radius for my modern equipment. They have a slight overhang, but you don't normally see it with the 89' flatcars. You could see it with Superliners and autoracks. It shouldn't really bother you, unless you want realistic curves.
I also have 12" curves they work with autoracks, coaches, and flatcars. It will operate fine no worries about changing the couplers.
Amtrak America, 1971-Present.
dehusman Prototypical? A 6 degree curve is 955 ft radius, that's 5' 11 in radius or 71" radius in N scale.
Ding ding!! The first reply to actually answer bebob's original question in a clear way - "prototypical" radius in N scale in plain US N scale units would be much broader than is practical on a home layout.
A radius which is practical is going to be much sharper or tighter; I'd suggest to the original poster to go as broad a radius as you can manage in your space.
How much space do you have to work with? An 18" radius curve in N scale is usually pretty decent and you can run long modern equipment on it without much trouble and looking decent.
Rio Grande. The Action Road - Focus 1977-1983
riogrande5761 ...I'd suggest to the original poster to go as broad a radius as you can manage in your space....
I agree! Since the OP mentioned that the layout will be a shelf-type, it's unlikely that there'll be any major curves unless the shelf is either extremely wide or is on more than one wall. Even a shelf 4" wide could have a 30" radius at the corner of the room, as long as the layout depth at the corner could be, at the mid-point of the curve, roughly 16" from the corner to the near edge of the shelf.Talk of minimum radii is useful when overall space is constricted, but a shelf can take up little space in a room and the extra width needed at the corners for wider curves is often otherwise wasted space anyway.