Hi, I'm not new to model railroading, but am new to starting from scratch.. can someone explain to me (for n scale) what the difference is between like Code 80 and Code 55 track?
~ Matt
Hi, I'm not new to model railroading, but am new to starting from scratch.. can someone explain to me (for n scale) what the difference is between like Code 80 and Code 55 track?
~ Matt
In the USA (and probably Canada), for all track, in any scale, the 'code' is the height of the rail in thousandths of an inch. Probably there's some metric equivalent notation that I don't know about for Europe and other 'metric' nations.
Thus, for N.A. at least ....
"code 40" has a rail height of 0.040" "code 55" has a rail height of 0.055" etc.
Prototype railroads used a WIDE variety of rail sizes (and shapes). The same railroad would use differnt sizes on various tracks, depending on expected loading and train speed. "Old Time" railroads used a LOT lighter rail than modern railroads (their rolling stock was a lot lighter too). Thus, some of the intermediate sized rail can be used as light rail in HO, or heavy rail in N scale.
The once common "Code 100" HO rail is heavier than HO scale for almost all real RR rail. That's why the "Code 83" rail has become popular in more recent times. It approximates the scale size of typical main line RR rail. For secondary track one can use "code 70" in HO, and even "code
55" for really light rail (old sidings, logging and mining track, etc.).In N scale, the equivalent main line ("code 83") size would be O.083" X
87/160 = 0.047". So, to be prototypical, you should not use any rail heavier than about 0.050" in N scale. Thus the popular use of 0.040" in that scale ... it's pretty representative of what a lot of railroads actually used.Dan Mitchell ============
For the metric equivalent just multiply the height in inches by
25.4mm/in."code 40" has a rail height of 1.02mm "code 55" has a rail height of 1.40mm "code 70" has a rail height of 1.78mm "code 83" has a rail height of 2.11mm "Code 100" has a rail height of 2.54mm
Be aware, though, that the height indication may not be precise. As an example I've found that ME code 40 is appr. 1,1mm high.
If that's true it means there is NO "metric standard" (I'd never heard of one), metric users just 'metricate' the english standard. After all, "Code 100", or whatever, means something intrinsic in english units, it means nothing in metric units. There's nothing unusual in doing so, it happens both ways in all sorts of measurements.
Dan Mitchell ============
True that some equipment will not operate well, if at all, on smaller rail sizes. Depending on what you want to run, that may set a lower limit on track size.
That's not the question that was asked, however, but it's certainly worth mentioning for a "newbie".
Dan Mitchell ============
It's the rail height, in thousandths of an inch.
So code 100 is 100/1000 or 1/10 inch.
The "Code" is the rail height (the metal bit) in thousands of an inch. Code 55 in N scale is about as big as the heaviest rail used by main line railways in the USa. Code 80 in N scale is huge, but is rigid enough for practical handling by children and clumsy adults.
I wonder if you're looking at Peco N gauge trackwork? Peco makes a Code 55 which looks reasonable but includes an extended metal base within the plastic sleeper base which adds the extra strength and allows it to mate with their normal Code 80 rail.
Those of us who use metric measurements just use the metric measurements!
2.5mm rail is equivalent to Code 100 2.3 mm = Code 90. 2.1mm = Code 83. 1.8mm = Code 70.Greg.P. NZ
Code 100 is _about_ 0.100 inch.
Each manufacturer makes their own profile of rail which varies a bit from the others and also the rail is made by squirting metal through a metal die, which wears over time, so the height intended to be 0.100" might be 0.098" to 0.105".
Those conversions, of course, are not precise, though certainly 'good enough' for the purpose.
I would suspect that 'metric world' manufacturers roll their rail to SOME metric dimension, perhaps those you state. In the 'english world' they do the same, using english units. Since the fractional millimeter difference this yields is not significant, comparable sized rails will still connect and work acceptably.
As for precision, I've found (probably) USA made code 100 rail that varies by plus or minus about 5% ... which is more than the conversion inaccuracy you imply. If the tolerances are that wide anyway, it really doesn't matter.
And, as for connectivity, the exact SHAPE of the rail from various manufactures varies considerably, which can make for some problems with non-matching rail joiners. It's also true that prototype rail comes in different 'sections', having distinctly different shapes and proportions (head, web, and foot, as well as filleting) in any given size. So, this too can be prototypical.
Dan Mitchell ============
Very true, which is much as I stated in my reply to your earlier post. It really doesn't matter in practice.
Dan Mitchell ============
The point I was trying to make is that they are not conversions. :-)
A large proportion of the trackwork available today comes from Europe (Roco/Atlas, Casiado etc) or Asia so it would be manufactured to a metric dimension.
Well, the prototype connection method (other than welding) is normally by way of "fishplates" which bolt to the rail web and bring the rail heads (more or less) in line rather than the foot as on our model tracks.
The fishplates actually are tapered so they wedge between the 'fishing surfaces' of the rail. ie. the underside of the head and the topside of the foot which are tapered to match, the fishplate does not touch the rail web*. Thus the alignment is with the bottom of the head and top of the foot. To connect worn to new rail or rails of different sizes special fishplates wwere used with a set in them to bring the running surfaces level. These have pretty much died out and rails of dissimilar section are joined by welding these days.
You've gotten all the details on how code is measured. The bottom line is this:
Code 80 is big chunky Atlas stuff you see everywhere. Code 55 looks WAY better. Most good code 55 brands have much smaller ties, spaced closer, and doesn't have the toylike look of code 80.
Your case may be similar to mine. When I started in N in 1985, I built everything with Atlas code 80 track. But now I use code 55 because it looks so much better.
You'll find Atlas code 55 all over the place. But beware, you may find that a lot of your equipment won't run on it because the wheel flanges will hit the ties. In the current new N layout I've been building over the past year, I went code 55, but opted for Micro Engineering, because it's just slighty taller (the rails) than Atlas, so everything I have will run on it, even Arnold engines with massive ugly flanges.
Micro Engineering is much more expensive, and harder to find, than Atlas. They also don't have the selection of turnout types, crossings, etc. But in my opinion, it looks much better and works flawlessly. I'm not the least bit sorry I went the Micro Engineering route.
As for code 40 --- good luck. If you are a purist, and have very small flanges on everything you own, code 40 will look great because of the tiny rail. But I don't think it's worth it.
============================================ Oh... one more VERY important thing about Atlas code 80 N Scale track. If you use this, and you buy the flex track sections (which you most likely will want) BEWARE that "some" of them are out of gauge. On the back of each section, samped into the plastic, are the words "Atlas" and a letter "A", "B", or "C". Do NOT use the "A" sections. Put an NMRA standards gauge on these and you'll see that they are TOO NARROW between the rails. On curves, this makes some engines derail, especially steam locos, and the tighter the curve and the longer the wheelbase, the worse it is.
Go through the box in the store, and hand-pick the "B" sections. "C" are usually okay, but I've found a few of these that are also too narrow. The guys in a train group I used to belong to couldn't believe this when we discovered it, but the gauge doesn't lie, and every single "A" section is too narrow that I've ever seen.
--- Max
Matt wrote:
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