Which radii did you choose for your N-scale layout?


Chevron_GATX

Chevron_GATX

Member
I have some fairly long locos, including the Bachmann EMD DDA40X "Big Boy." I was planning on adding multi-loco trains using three to six SD-40s, SD-90s (or a combination of both) in tandem. My current freight inventory includes only a five-car stack-container car that I just ordered. I was planning on building a very long consist of 31K crude-oil tank cars as well. I'm reviewing my space options and haven't yet chosen any sort of layout yet. So, my primary freight consists:

• 4-6 five-car stack-container well-cars.
• 10-20 fifty-foot Railbox box cars.
• 20 or more 31K crude-oil tank cars.

I guess my question is: What is the minimum radius (for 180° turns) that doesn't look "wrong?"

 
The Kato Unitrack V11 kit I bought includes: "Kato N 20182 Unitrack Concrete Tie Double Track Superelevated Easement Curve Left and Right 381mm/414mm Radius 22.5 Degree (15"/ 16-3/8")."

Regarding others' recommendation for "minimum" realistic-looking radii, I read Iron Horseman's reply to a member in another thread that I'll re-quote here (hopefully, he won't mind): [Regarding minimum "acceptable" radii for N-scale layouts] " . . . Short answer - yes 8" is way too short. Long answer - 9.75" is the N-scale equivalent of 18" radius in HO. Considering your space, I would be thinking more like 13" minimum, but attempt to get 15"-16"."

So, I take it that most would agree that a 16" radius will be "okay" in N-scale (of course, bigger always being better). I'm guessing that the first number in the Kato specification is the "length" of the track, and that the second number is the radius? So, assuming I have a 16-3/8" radius, this makes my 180°-turns total 32-3/4" in diameter, correct? If so, this is good, since my table is only 32" deep (so I'll only need a small extension to accommodate this initial layout). I was thinking that a decent-looking radius, even in N-scale, would've been larger.
 
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I am going back quite a while. In the late 70's I built an N scale layout with over 11 scale miles of main line and numerous industries in towns along the main line. I had a small N scale layout I had started when I was stuck in an apartment in Florida when I was in an apartment that I incorporated into the big layout.

When I built the small layout I was introduced to flex track and never looked back. A guy that worked in the hobby shop that I was using opened a new world to me in model railroading. Never touched sectional track since. after using the broader radius that could be accomplished with flex track, the layout didn't look so toy like. Most of the radius were 26 to 30 inches in N scale with some even broader. I like to run passenger equipment which looks so much better on broader curves. There were some curves in industrial areas in the 10 to 12 inch radius area.

You seem to be quite committed to Unitrack which limits you to sectional track and set radius curves. I found that sectional track could be difficult to work with especially in yard and industrial areas trying to find short sections of track to make everything fit and look correctly. After moving to flex track, it opened a new world to me. It was so much easier to cut a small piece of flex track to fill in between turnouts in yards and industrial areas. I could also have the main line easily weave through scenery with broad curves, probably up to a 60 inch radius in N scale and easements into curves were more or less taken care of automatically. Going to flex track and using turnouts such as Atlas and Peco could possible be less expensive also

The broader the curve you can use, the better.

In my HO scale layout things were a bit different working in a larger scale but most of my curves in HO scale are quite broad, 48 inches or more with one area where the minimum radius had to be brought down to 32 inches. I started the layout hand laying code 70 track and turnouts but completed it using Shinohara turnouts and flex track.

I have been watching your posts and I am looking forward to see what you come up with.

Good Luck.
 
I'll double Chet's suggestion to at least look at using flex track, because it does open up so many more options. I'd also suggest AnyRail software program to design your layout if you're worried about trying to actually lay the flex track, because you can quite literally print out your layout and glue it to your table. Basically have your entire layout drawn out for you to exact dimensions with lines telling you exactly where to put track, turnouts, everything.

But back to the specific topic: From what you're describing on that Kato track, I would think it's a double track section where 15" is the radius of one track and 16 3/8" is the radius of the other outer track. AnyRail actually says that outer track is a 16 19/64" radius, but that may be old info. I'd say that for any mainline operation at high speed, 15" radius is about the minimum. For my personal preferences and what I've observed, it may actually be a little below minimum. On my mainlines I actually designed everything using an 18" minimum and that does look okay. The 21" curves look even better. If I'd had the room I would have made 36" curves in places, but that would have voided a lot of real estate. I do have much sharper curves on my local and sidings, down to 10" in two spots on the line and even 8" on a couple of sidings. That works fine for 4-axle locos, slow speeds, and ~50' cars. I have notched up my local and let it run around that track at full speed to test the trackwork, and while it does run just fine it also looks pretty comical and unrealistic. For passenger equipment or things like auto racks it would be downright ludicrous. I'll also note that my "full speed" or "high speed" is actually a relatively low speed-match on all my locos of about 50 mph scale speed. So we're not even talking about the rocket ships that some locos tend to be right out of the box. Even that relatively low scale speed still looked pretty ridiculous when you get down to 10" radius.
 
Hey, thanks guys! I really appreciate the input. Lots of good info there (good point about the two-radii specification, Mike!) I know that Flextrack is really the better way to go. Once I lay the interior tracks, an outer-rimming Flextrack install would be perfect for, say, an Amtrak Superliner. Meanwhile, Unitrack at least allows me to quickly prototype (in the "testing" sense) various designs, so it's a good place to start for someone like me.
 
My current benchwork (Home Depot cabinets) is only 20" x 12' (which is too narrow to accommodate a 180° turnaround). I was planning to extend each end to a depth of 36", but that'll barely accommodate a 16-3/8"-radius track (requiring 32-3/4"-depth for a 180° turnaround). Add a minimum of 2" on each side, and that grows to a depth of 36-3/4" on each end of the dogbone.

I'd probably rather have a bit more track-buffer, so say, 4" on each side (in addition to the fact that I was hoping to add multiple, offset circuitous mainlines). This increases the end-depths to 40-3/4" (which, hopefully, is still shallow enough to reach the rear of the layout). So, instead of 'L'-shaped benchwork, I think I'll actually need 'U'-shaped benchwork to accommodate the required turnarounds.

However, if using this basic layout, only one section of track will be near the perimeter of the benchwork, so perhaps a 36" extension is okay:

katounitrack-4.jpg
 
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Chevron_GATX said:
Hey, thanks guys! I really appreciate the input. Lots of good info there (good point about the two-radii specification, Mike!) I know that Flextrack is really the better way to go. Once I lay the interior tracks, an outer-rimming Flextrack install would be perfect for, say, an Amtrak Superliner. Meanwhile, Unitrack at least allows me to quickly prototype (in the "testing" sense) various designs, so it's a good place to start for someone like me.
Click to expand...

I actually love Unitrack, but it does cost more and doesn't have the flexibility I need for the almost ridiculously track-heavy design that is my layout. If you don't mind the price I'd say to use it wherever you can, but it is also easy to transition to flex track when you need to fit in something oddball. I have some Unitrack around my turntable and on a few curved viaduct sections. Their roadbed is a tiny bit taller than cork roadbed, but you can adjust for that with some cardstock laid under the cork. I've even just let it hang in the air, so to speak, for a couple inches as it returns to the cork roadbed level. Once you have it ballasted you can't tell, and as long as you don't force it to return to that level too quickly it's an almost unnoticeable grade change. The one caveat to changing the track type like that is that to my mind you do have to solder the connections when you do so, because the rail joiners don't fit quite as tightly as I'd like them to. You may not feel the same way, or someone here may offer advice on rail joiners that do clamp more tightly than the Peco I use. I'll also note that I basically solder all my rail joiners anyway when it's not Unitrack-to-Unitrack, so I may be guilty of overkill to begin with.
 
Chevron_GATX said:
My current benchwork (Home Depot cabinets) is only 32" x 12' (which is too narrow to accommodate decent 180° turnarounds). I was planning to extend each end to a depth of 36", but that'll barely accommodate a 16-3/8"-radius track (requiring 32-3/4"-depth for a 180° turnaround). Add a minimum of 2" on each side, and that grows to a depth of 36-3/4" on each end of the dogbone.
Click to expand...

Remember that the radius is measured from the center of the track if I'm recalling correctly. So the 16 3/8 will actually be slightly larger as far as the actual real estate it takes up once you add in half the track width and the roadbed. It's not really an issue for the most part, but if you're looking at squeezing things down to absolute minimum required space you'll need to take that into account.
 
Thanks again for your comments, Mike! Yeah, I think the Kato viaduct track looks super-cool, especially for an urban light-rail line. I don't think soldering is overkill at all. If and when I go Flex (or, more likely, manage to make a few Unitrack-to-Flex connections), I will definitely be soldering the heck out of it.
 
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MikeOwnby said:
Remember that the radius is measured from the center of the track if I'm recalling correctly. So the 16 3/8 will actually be slightly larger as far as the actual real estate it takes up once you add in half the track width and the roadbed.
Click to expand...

Ahh . . . good point! At least the Unitrack will be dumb-ass easy to prototype (in the "testing" sense). I'll generally be "designing" as I build so I can "see" what actually works, visually. I'm definitely planning on going through dozens of iterations, so that's why Unitrack is probably a good fit for me to start (in addition to the immediate-gratification benefit). Obviously, the Kato V11 kit I just ordered is just a starting point. I also ordered some truss bridges and whatnot to be able extend the middle of the dogbone, right-off-the-bat. Remember, I still have to decide where to place my 10-lane freeway (I'm thinking of a cross-section design), plus a 10' airport runway!
 
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I am such an idiot! My countertops aren't 32" deep, they're only 20" deep! Since slab doors won't fit conveniently on my existing benchwork, I'm thinking of using melamine 3/4" stock instead to extend the effective depth of my cabinet-tops. I was thinking of using Home Depot-stocked melamine shelving material:

• 4' x 8' melamine 3/4"-stock (cut to some width narrower than 48")

My "bare-minimum" radii requirement is 36.75", and my "preferred minimum" for 16-3/8"-radii track is 40.75", but I have only a 20" deep countertop. I can cut a 4' x 8' sheet to the desired "extension depth," but that'll be way too much material to overhang without any support. Back to square-one.
 
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I've got it! I have a pile of extra Ikea extruded aluminum shelves which give me a total depth of 41.75". The extruded aluminum and a thick sheet of metal underneath allows rigid support without using any brackets (so the cabinet doors remain operable). See photo in my "small-build layout progress thread."
 
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