Dear all I am new in this forum and also just started with N-scale, topic north american railways. I would like to ask members here which minimum radius is needed to operate trains properly which have 40 or more boxcars ( lets say 50 feet boxcars). Furthermore, I also plan to buy Big Boys to extend the train length to about 100 cars:tb-biggrin:. Thank you for all your answers and best regards from Switzerland md11
md11: Here is another thread on the same subject. In any scale, the larger radius the better. For 50 foot boxcars, I would say 35 cm. You should get some track and experiment to see what looks good to you. If you run Big Boys then they will probably be the limiting factor for appearance. One hundred car trains create a lot of drag on smaller radius curves. This brings us back to the original concept...the larger radius the better.
Welcome to Trainboard. There are two issues here. 1. Radius for good operation- I would not suggest going with the tighter radii. 2. Someone here with knowledge will post soon about Big Boys on tight radii. My suspicion is that it will not take the tighter ones. Also, be aware that the pulling power of a locomotive is also affected adversely if you have a turn on a grade. The most important thing is that your trackwork be perfect. If there is anything that is going to toss a boxcar in a long train off the track is a kink or a gap where there should not be one.
50 Box cars X 5" = 250 inches or over 20 feet. You will need to be planning a large layout to justify that size train. I'd like to suggest a smaller layout or one that can be expanded into a larger one later. Take time to learn the skills required to have smooth running trains. This will also get trains up and running faster thus avoiding the discouraging feeling when you feel you have bitten off more than you can chew. As to your question: What they said - Broader curves function and _look_ a lot better.
Welcome to TrainBoard! Don't forget that to get prototypical looking curves that are still navigable into a smaller space you can use easements, curves with radii that decrease toward the center of the curve and increase away from it. If using segment track you can simulate easements by using smaller, say 11" radius segments at the middle of the curve and larger, perhaps 19" radius outside of them. Of course we'll probably see some responses shortly saying my 11" radius center is way to small, but remember that its how it looks to *you* that really matters.
Welcome to TrainBoard! Always go with the largest radius possible. Not only will it look better, but you'll have chances for fewer derailments. The larger your equipment, the more poblems, as the curves become tighter. For my own use, I try to stay 18" and above. Less only on an industry track. Boxcab E50
Wide curves are the best curves. If you take a look at my layout you will discover a "Spagehetti Bowl" of track, grades and various types of trains negotiating it without problems. An experienced fellow model rail came by to look at the layout, I was bragging that my main line had a minimum of 18 inch radius. He challenged me stating I had at least two sections of 15 inch radius and yes I do. I will explain. What amazed him was my 40 car freight train that handles the grades and curves with ease. When I pulled this long and lanky train out from the staging yard his first response was, "Oh, boy we are going to be picking up cars off the floor". It didn't happen. I then ran my 30 car freight and my ten car "Daylighter" and others that impressed him as well. The minimum I strive for is 18" radius on the main and 15" allowed in the yards (which is where we found the 15" radius curves) and 11" for industrial spurs. We did find, one other mainline curve (the one that circles the roundhouse) it is 16 1/2" radii on the inside curve. Grades: Most of the curves on the layout are on grades. I use them to climb as in the Triple Helix. Something, I learned from my earlier days in HO, S and O scale. I will echo others: The track must be laid meticulously (be a perfectionist). The wider radius is the best radius. 18" Minimum. Track joints must be smooth and not kinked. Everything from wheel sets to track must be to proper gauge. Purchase an NMRA N Scale gauge. Freight cars to be kept to an ounce and wheels free rolling. The less drag the better your train will perform. I'm not heavy into easements however, I utilize such and find it easier to do with flex track. Grades: Minimize your grades to 2%. Defined to a rough approximate that is 1/4" rise to every linear foot. The wider the curve, the more linear feet to work with. I have one curve "Stan's Curve" that is exceptional and everything looks good as it passes over it. It is a 24" radius curve. You've got to have at least one of these. I hope that helps and have fun!
I have a small layout and an Athern bigboy as well as Kato GS4. My layout is only 6x3 feet so real big radi was impossible. Both engines have min radi of 11" and do run on them but it looks horrible. the big boy hangs over the inside track quite a bit. My min rad is 13" which isn't too bad but I also have a 3% grade with turns and while the engines will do it they don't like it. When pulling the 10 car daylight it slows quite a bit ( hoping DCC will fix that) So bottom line Go as big of a rad as your layout can fit (at least for the mainline) I'd try to stay at 2% grades or less and try to keep them off turns (really surprised how much that effected the engine). If you need to use small radi turns keep them level and hide in tunnels. And finnally definatelly get a Athern bigboy. It's such a fun engine to run even on my small layout.
Don't think in terms of what minimum radius you can squeeze in, use the largest radii you can fit into your space. I wouldn't go less than 15 inches unless I had to. Let the guys in the larger scales use ridiculously tight curves to shoehorn track into their layouts, the ability to use relatively broad curves in relation to the size of the trains is an advantage of N scale. Its interesting to compare our minimum radii to the prototypes, here in Brisbane where I run commuter trains on the 3'6" gauge there is for example, one mainline curve of 145 metre (475 ft) radius which translates to 35 1/2 inches in N scale, but in real life it looks very tight and has a 30 kilometre/hour (18 mph) speed limit.
Compare our curves with the prototype. Somewhere I read that the minimum curvature needed for a prototype SD 40-2 was 242 feet. That translates to 18.15 inches in 1:160 scale. You will never find such a small radius on mainline RR's. The radius of the old PRR Horseshoe Curve was 609 feet and 637 feet respectfully. And that was very tight for a mainline. That translates to 45.67 inches and and 47.75 inches respectively in 1:160 scale. A lot of times people start out with a small starter set consisting of a four axle diesel and some 40 foot cars. They design a layout using minimum radius and after getting everything up decide they want to run passenger cars with PA's and 85 foot cars. So use the largest radius you can is a good rule to follow,
Yes, I agree with that rule. This is where I'm coming from though. I want to build a small 24"x66" layout. I'm going to make it a twice-around. The largest radius curve I can use is 11". But that just gives me an oval, figure eight, or something like that. For a twice-around I need an inner track with 9 3/4" radius curves. I won't be running trains longer than six cars, and I won't be running any modern era 85 footers, so it should be okay.
Good advice here. I run a minimum of 18-inch radius, but even that's too small for big steam and 85' passenger cars. I'd rather go 3' x 3' than 2' x 4'.
I guess... ...I'll enjoy mentioning that I had a 9-3/4" radius 180 degree turn on my MCL a couple years ago. I usta run 35 car trains thru it with 3 Kato SD-45s. Of course it was a bit glaring to watch the RDCs run thru but I managed. I also managed to back thru the same curve pushing 35 cars. Track was Kato. Heh. Mark
Lark - trouble maker //just joking. Yes, you can do that with Kato track and well weighted cars or maybe you don't even need those. That said, I bet you agree with the advice given here as well. I have broken a couple of rules using Unitrak but I always encourage folk to proceed at their own risk.
Why does this question keep popping up here? This question jumps up here from time to time. I guess it's just me...but I'm amazed when someone asks how tight a radius they can use? Or, what's the minimum? Oh, I understand someone who is just starting out and wants to put as much railroad as possible, into a small space...Ie., A coffee table. I've seen a few of these. The opportunity to have wide open curves to almost prototypical proportions is to much of a temptation for me to pass up. You can run the tighter radius and have loads of fun. I did that with HO. Funny thing happened to me as I was building my N scale layout. I used HO dimensions to lay my N scale track. Let's see N scale, 15" radius is the approximate equivalent to HO's 30" radius....18" to 36", 24" to 48" and so on. Although, N scale is not precisely 1/2 the size of HO scale... it's close. It's your choice to run tight or run wide! Have fun!
Sometimes I wonder if... ...radius is confused with diameter. A 9-3/4" radius is 19-1/2" diameter. Pretty good for turning an N Gauge (there I said N Gauge) train in "tight" circumstances. Just me again.
I still think a 19-1/2" diameter curve is too small, except for a switching layout, or a layout that runs small engines and short cars. My smallest diameter is 36", and some longer steamers and passenger cars look pretty funny.
The variable here is what size are you going to make your layout. A large layout in a room that can accomodate a significant HO layout can easily see curves above 24" which is a good sized curve in N scale. If you have room, make all your curves above 30" and you won't have a problem with the big boys. Also something to consider is the ammount of track you want. Do you want a "spaghetti empire" or long mainlines with scenery and a few sidings here an there, i.e. more of a railfanning layout? Right now I have a door layou with 15" radius curves since I move alot (military) when I get that place I can settle down and build a large layout, I'm going to build mine with very large curves since I like large mainline locomotives and it will be built more for railfanning with some industrial switching, plus a logging branch that will feed my switching needs.
