My train room is 14 x 18 so I have a good bit of room. I want a realistic "minimum radius" that will make the trains look like trains are supposed to look like in a curve. I plan to super elevate the main lines. I believe that a wide radius curve will be worth the space it requires, I just don't want to make it too big and waste that space.
In my albums I discuss and share pictures of and assortment radii curves. You might find this helpful. Click on the invite below and go to the discussion on "Radius Of Curves".
You could draw various radii on a large piece of paper, then place your longest cars and engines on each curve, when you get to one where you think to yourself "that looks ridiculous", you've gone too low. Depending on the track plan you want to fit into the space I wouldn't go tighter than 15" as a minimum, 18" would be better. Also, minimum is just the minimum, go for some wider curves where you've got room, instead of long straights, use long, sweeping curves. Another consideration is that tight curves don't look so out of place in mountainous territory as they would out on the prairie. I believe that using the largest radius you can for a better appearance is less a waste of space than using the tightest your rollingstock will squeeze around so you can fit in the maximum amount of track.
Also, be aware of where you can break the minimum radius and get away with it. Just because a train looks its best on xx radius, doesn't mean you absolutely must use that radius even if the specific curve is under a mountain or hidden behind scenery/structures. Using that technique will help you save space where it's unnecessary to go broad, and therefor you'll have more room in the visible areas for wider curves. But you don't have any "hidden" areas you say? Make some! I'm not saying put in tunnels, but plan for areas were the trains will duck behind buildings, trees, a hedge line. Have the train play peek-a-boo.
If you got 14 X18 feet to work with then I say go big. Your minimum mainline curve should be no less than a 30 inch radius. I run Ntrak and typically we have corners that are either three feet [3x3] or four feet [4x4]. Due to track set backs we loose 8 inches. Add in another 1 inch for an easement and we are now down to a maximum radius on the three foot corner of 27 inches. Adding in the two other tracks that are 1.5 inch on centerline and we have the three radii of 27", 25.5" and 24" for the three tracks. On the four foot module we have the same setbacks and easement so the max radius is 39 inches and the three track radii are 39", 37.5" and 36". Because the three foot modules are a lot easier to pack and transport we tend to use them more. But there is a tremendous visual difference between the radii differences on a four foot and a three foot corner. It is most noticeable with long cars like passenger, autoracks and TOFC's. So my advice is if you got the room [and you do] then go big. One more thing, keep your straight track to a minimum. Put some curves in it and make it look like it was built to follow the terrain. After all you are building a railroad not a racetrack.
It is, isn't it. I thought you might find it helpful. As noted here by Westfalen, Mystere and Inkaneer you can use your wide radius curves up front where they are seen and take to a tighter radius in tunnels or other less visible spots. You might have noticed I used a wide radius in my helix. Since the train is pulling a grade and a curve has a tendency to cause drag, I allowed for a much wider curve. My trains make the pull with ease. Glad you could be here to ask. You're going to like it here I guarantee it.
Ten degree curves are normal out here in California's mountainous terrain. In N-scale, that equates to a 43" radius. Your trains would look stunning on a curve this size! The problem is, it will take almost eight feet to turn your trains. If your layout is around the walls, it may not be a problem,but an island style or peninsula may pose a "space-eating" issue. Honestly, you could obtain very believable results using a 24" radius, which represents an 18 degree curve. It's a little sharper than what you might find on the mainline (perfect for branchline), but you can easily get away with it in N-scale. Go with 24". Donnell
A ten degree curve is a sharp curve for mainline RR's and calls for speed restrictions even with superelevated track. A 43 " radius in N gauge equates to a protypical 573 foot radius. Horseshoe Curve on the old PRR mainline has radii of 609 and 637 feet and 90 foot autoracks and TOFC's squeal like piglets going around it.
Hi, I have a 20x16 layout and use 36 inch radius mostly and around the corner coming into the yard and passenger station, I elected to use 48 inch radius curves so they would look good coming in and going out. I found having a showcase section of the layout is a good compromise with the space issues leaving the rest of the layout to be a little tighter.
One thing I always stress when people start talking about minimum curve radii is the use of easements. Even for people who are using sectional track, starting a curve with a piece with a larger radius, can help out a lot, both operationally and visually. You can have the curve radius large enough that your trains will look fine going through them, and, without easements, they can still look odd going into and out of the curves. As the train enters or exits a curve, without easements there will be points where one car is completely on the curve and an adjacent car completely on the straight section. The overhang on the car that is on the curve causes the ends of the car to be misaligned(this is especially apparent with passenger cars where it would often be impossible for the "passengers" to cross from one car to the other). Having easements can drastically reduce this effect and in my opinion greatly improves the look of the train going into and out of the curves.
My 2' x 4' test loop uses 11" radius curves (sectional track) at each end, but even so I use a section of 19" radius as an easement in and out of the curve just to keep stuff on the tracks. It still looks ridiculous for passenger cars and 6 axle diesels, but the with no scenery, it looks ridiculous anyway <G>.
Doug, What brand of track are you using? I have had the same idea of building a test track and using the 19" easements on each end of the curved sections. I would agree that it would look ridiculous for passenger cars (mostly what I have) but it would be a good place to play with lighting, decoders and breaking in new locos. Terry
Update: I dumped my albums and the discussion on radius curves is no longer available. I'm working on something different but it will take time to complete. I'm glad you got in on it at the start of your thread. The discussion here about easements is worth the read. I use a type of easement on my layout but I find it difficult to plan. Enjoy your layout.
How do you get 24" radii in that space? Are you able to fit a turn around curve? I have a space that's 11' x 15', building a j shaped layout around the walls and can't seem to keep the radii above 15"
Hello! I m an N-Gager from Russia. I m making a layout on base of Atlas Code 55. As about curving and reality: There are too little space in our Russian rooms, and therefore there are strategy of making small (about 8") but hidden into tunnels U-turn radiuses at the ends of layout in aim to make small layouts with round way scheme near wall, so that on opened places of layout radius may be 15"-20" or straight line. Therefore layout looks like two way straight or slightly curved line and looks realistic! Another problem - some american locos have coupling on their body(not at trucks ), and light cars, attached after loco can derail at this strong radiuses in tunnels. Therefore they requires some remaking or not using.
It is not just the problem that cars are derailing because they are too light in weight. That could be corrected by adding some weight where possible. However, some cars can't negotiate the curves at all. I just got one of the beautiful cylindrical hoppers made by North American Railcar Corporation, and I now found that they can't get around a 9" curve. Intermountain has a very similar model that does not have the slightest problem with that tight radius. It is the cross bar that holds the trucks that is a bit too wide in the new model. This may be prototypical, but I prefer compromises where they don't really hurt.
Ok, Thanks, I explain problem more precisely. When You have body couling at loco (for example as at Life-Like RS-2), which pull train at heavy turn where first car has coupling on truck, the truck will expose angle force (or momentum )due to skid of loco back, therefore this truck will tend to ride on this angle which dont coincide with track direction, and as a result - we are having derail. MicroTrains fine universal coupling (in comparison with Atlas )have more flexible springs, but coupling change does not solve this problem at all. Another possible solution - reduce angle momentum. It can be achieved by changing Atlas trucks of car onto microtrains ones. In this trucks couplings are more closer to center of truck( to King Pin ) and this force can be reduced. Third solution - make first car with one coupling on body! It's Finest solution, but there are usually no free space between car end and truck body in aim to skrew onto it microtrains coupling , because trucks usually placed too close to car ends. 4-nd solution - usage of pizzacutters - like wheels (for example Atlas Metall instead of FoxWalley ) which have large flange, and improove stability against side derailing force! 5-nd solution - usage of extra weight, as was suggested, but this fact reduce length of train, which loco can pull on heavy slopes. --------
Here is an update with a format I like. Here you can see examples of various radii and how passenger cars look on an assortment of curves. Overhang is the key here and it get's real obvious in this presentation. http://www.barstowrick.com/tight-radius-curve/ Oh before I forget, it really wasn't that difficult to plan 24" radius curves into my layout. It all depends on what's driving you. While visiting my blog feel free to look around. You'll find The Howland & Pacific Railroad with videos and you can see my folded over pretzled dog boneof a layout. I have a good friend that calls it a cluster f..., Yep it's what you thought I was going to say. This is all about choices you can make. Have fun!
