Hi guys,
OK, limited space dictates that my maximum radius at this one place is 18" which would be fine for On30, and better than fine for N Scale.
However, if I wanted to go HO, how horrible would it be really?
We’re talking transistion era, no huge steamers, passenger traffic would be RDC’s.
If the problem is only that it’s ugly, then the given of space limited overrides the druther of it’s ugly.
If the problem is a given that stuff will derail all the time, then that’s a deal breaker.
thanks
As long as you don’t run passenger trains and stick to shorter locomotives and freight rolling stock it should be okay. But no AC4400s, SD90MACs, or 80 foot passenger cars. Forty foot boxcars, reefers, coal hoppers, and gons would be okay. Forget about auto racks or double-stack container trains.
It depends on what you’re willing to live with. The curves on my layout are ALL 18" radius and I run locos as big as E units and SDP40F’s (even bigger) without incident around these curves and through #4 turnouts with no modifications. If you don’t believe that you’re more than welcome to come and watch them do it.
Here are a few photos showing what 40, 50 and 60 foot rolling stock looks like on 18" curves.
Unless a locomotive specifically says something other than R18", you should be fine. As far as rolling stock: 50’ and longer should navigate through R18". It just won’t look pretty doing it.
Tom
If you like Lionel you will love 18" radius curves. Sooner or later you will want to make them bigger. I used 30" for many years (I know I had more space available) and currently am building with 48" curves. If that is all the space I had I would consider N seriously as that is the equivalent of roughly 36" in HO.
Yes, that’s why I’m asking the question and trying to ponder which way to go.
This is not a ‘forever’ layout because, well it’s not a ‘forever’ house. Plus, With HO I’d be able to run stuff with my club, etc. etc.
Jeffery: I look forward to looking at your pics when I get home
thanks to all.
sorry double post
It’s a fact…in an urban area with trolley tracks, or in the back woods where a Shay is at work, tight curves down to 12" would look right at home on some layouts in HO. Eighteen inches is the recommended minimum, and is at the bottom end of the range of “tight” curves for HO scale.
It’s a fact…that long engines and passenger cars or auto-racks look rather silly on really tight curves, even if they can actually get around them 100% of the time. But, without the room, what’re you gonna do?
None of us can have it all. You must learn to deal with compromises in our hobby. Trade off some reliable running in tight curves as you must, or do without more of one with the other as it suits you. Generally, there is no substitute for some real room to build a layout. But being able to lay really good track helps a lot, too. With some solid skills you can get your stuff to run well on very tight curves. For the trade-off again, do you want to invest the time it takes to tweak track and rolling stock to make it all work together?
I’d say, for what you describe, and to meet your desire to run stuff with your club, go with the 18" radius.
I set up a lot of ‘temporary’ trackplans using 18" sectional track to keep my five-year-old happy while the main layout ‘slowly’ progresses, and can attest that a LL P1K RDC will track happily around an 18" radius curve. A single RDC will even track around a 15" curve, but not if it is coupled to anything else - round an 18" curve, you can just get two of them to pass. Do they look silly? Perhaps - though at ‘eye level’ they look better than from higher up. My little guy and eye regularly ‘eyeball’ the track - things do look different from an HO trackside.
Jim in Ottawa
Great photos, Jeff!
But note, standard Lionel is 31" diameter curves, not radius - equivalent to 8.5" radius in HO, not 18" radius.
Jim in Ottawa
Era and prototype can drive suitable minimum radius as much as scale does. Consider that a 40ft boxcar in HO is slightly shorter than an 80ft passenger car in N. A 10 car freight train pulled by a branchline locomotive in HO is over a foot shorter than a 20 car freight in N pulled by double-headed road locomotives. Which satisfies you better?
The Layout Design Special Interest Group has a very good article on curve radius here: For 40ft cars and small switching locomotives, 18" radius in HO meets the 3X (3 times length) criteria for reliable operation. At the 2X point, you can use 65ft scale length equipment. But - the further you deviate from the minimum 3X recommendation, the more testing, equipment modification, and excellent trackwork will be required for reliable operation. The extreme is the Lionel O27 line which typically is in the 1.1X to 1.3X range. It’s done by a very large flange fillet (in the tubular track, not on the wheel itself), total lack of underbody detail near the trucks, truck-mounted couplers, greater than prototypical coupling distances between cars, and bodies often raised unrealistically high above the trucks. Stringlining for longer trains is an accepted fact of life in the O27 world.
In the HO world, getting to curve radii tighter than 2X almost always means truck mounted couplers, and details cut away or omitted as necessary to permit adequate coupler and truck swing. Sharper curves definitely increase the likelihood of stringlining if trains become very long. As Jeffery has shown, sharp curves in the 2X range can be done, and operated upon reliably. But there are no guarantees except that sooner or later you will run into a piece of equipment that won’t do such a sharp curve without some modification.
In the end, the choice is yours. I use and have used 15"-18" radius curves in HO and HOn3. But I deliberately chose short lines and the 1900 era to better m
I also think, given what you describe, that you’d be very happy with 18" radius. Bigger radii really starts to take more serious real estate than most of us have. I run 18", and can’t use most standard sized passenger cars – that’s my only regret. Otherwise, I can do anything I’ve ever wanted with it.
Long ago and in a faraway land, my first layout had 18" radius curves. That’s because I was using sectional track and that’s all that came with the train set. At the time, the longest car that was readily available was the Athearn 62’ tank car. Over time, I went to larger radii as I acquired more space.
But if you are limited in the room that you have for a layout and want to model in HO, don’t let the “ugly” factor get in the way. Sure, larger is better when it comes to radius, especially in terms of operation. Overall, however, I think way too much is made of how “prototypical” longer cars look on sharper curves.
John Timm
Aesthetically speaking, I think it looks awful…
To much truck/pilot/cab overhang and the gap between cars is huge on curves…
But like you said, if that’s all you have space for then you do what you need to do.
What size space are you talking about?
The only thing that would have heartburn with 18" radius curves is your RDC - if it is full length (the old Athearn RDCs were shortened.) Even then, while it might look bad, if running alone the only question is, will it take the curve? If the answer is yes, you’re good to go.
An unbuilt part of my layout will have 350mm radius curves (just under 14") - but, the rolling stock that will be using that track is all either short or hyper-flexible. Things that can’t take the curves are embargoed from that route. (My mainline minimum radius is 610mm, adequate for the short locomotives and cars my prototype ran.)
Chuck (Modeling Central Japan in September, 1964 - 1:80 scale on 16.5mm gauge, aka HOj)
I am using several 18’ radius curves on my layout, one in the “main” (a partially hidden continuous running connection that is part of an industrial track on one end and a wye on the other) and several in some steel mill industrial trackage. The normal operating, point to point main will have a minimum radius of 24".
On the other hand I am operating a 1900-1905 era layout where my average freight car is in the 34-36’ length and an average passenger car is in the 50-70 ft range. A small 2-8-0 or a 4-6-0 will be my largest engines.
It really boils down to what you can stomach vs what you have to compromise to run trains. If you ONLY have room for 18" radius curves or else no running trains, then go for the gusto. Just remember you are at the lower bound of the design spectrum, especially will larger equipment. If it makes you naucious to watch SD90’s and 65 ft centerbeam cars whip around a 18" radius curve, then don’t do it and settle for a switching layout.
I’m happy with my 18-inch radius curves in HO. As many have already said, it lets me run trains and still have a bit of space on a 5x12 foot table. I’ve chosen to run short diesels and short freight cars typical of the Transition era. I do have some 70-foot passenger cars with truck-mounted couplers that look a bit silly going around the curves, but that’s the space I’ve got. The 180-degree curves at the ends of the layout are disguised with a lot of structures and scenery, so the visual effect of the tight turns is minimized because only a few cars are visible at a time.
I have a friend who, because of space constraints uses sharp radius curves, but he hides them under mountains on one end of his layout and under an elevated city scene on the other. The result is that virtually all of the visible track is straight and the sharp curves don’t detract from the overall effect. His only limitation is the length of the equipment that can physically operate on his layout and it is surprising how many large locomotives and cars can handle 18" or smaller curves with no trouble. Abbie
How big is you layout anyway. If it’s a standard 4 feet wide, then you can fit 22" Radii track, but bearly.
Any smaller, 18" Radii is your only hope. It’s okay though, there are thousands of locomotives maunfactured with 2-axiled trucks by various companies. From Broadway Limited Imports to Life-Like by Walthers. On a small layout you’ve describled, you can’t fit many big or medium lanforms, and small towns or parts of cities are an idea. Don’t get upset if you can’t do fancy settings, but even a simple station can become a featured article in Model Railroader if you take your time and put your heart and time into it. Even if it isn’t featured, and isn’t “All-That”, it still makes your feel good that you’ve built it. That’s why I prefeer kits over prebuilt. (Except Locomotives) If you need track plans, look around, your on the number one spot for tips and information; Trains.com! My EMD SD40-2 sqeaks on 18" Radii, but I’ve never had a derailment problem due to the sharpness of the turn, in fact, my friend can run his Southern Pacific “Daylight” No. 4446 GS4 4-8-4 on his layout with 18" Radii turns! Sure the drawbar looks like it will smack a pole down, but it ran very nicely, and you don’t really care or notice the stress the train is taking. Also, you may or may not be able to run 3-axled trucked locomotives depending on how spread out they are. If they are far apart (i.e. EMD SD70ACe) or close (i.e. EMD SD9) will determine the cabitlity of the locomotive. The final factor that plays a role, is how much room the trucks have. If they are jammed together, or widly spread apart, like a Dash-8 locomotive’s.
Good Luck,
Josh