Track Question

Discussion in 'HO Scale Model Trains' started by M Gray, Jan 23, 2007.

  1. M Gray

    M Gray New Member

    Hello All,
    Could someone please explain the difference between the Code100, code55, etc..
    track designations? and which one is better for any specific uses?

  2. Triplex

    Triplex Active Member

    The code means rail height in mils (thousandths of an inch).
  3. CRed

    CRed Member

    I believe its the height of the track in 1000ths of an inch with code 83 being the most prototypical.

    I think Code 55 is an On30 deal,not sure though.

  4. LongIslandTom

    LongIslandTom Member

    For HO scale, you really don't want to go any smaller than Code 83 due to the size of wheel flanges on HO-scale locomotives and rolling stock. Any smaller than Code 83 and you risk the flanges hitting things like the molded tie plates or fouling the turnouts.

    So basically for HO you have only two practical choices: Code 100 (bigger rail at .100 inches high) or Code 83 (smaller rail at .083 inches high). Code 100 is cheaper if money is a consideration.

    Hope this helps.
  5. M Gray

    M Gray New Member

    sorry about wasted space, don't know what happened..
    Anyway, thanks for the quick responses.
  6. M Gray

    M Gray New Member

    what if the track doesn't not mention a code? it just says EZ track or whatever?, what height would it be?
  7. LongIslandTom

    LongIslandTom Member

    Most likely Code 100.

    Hope this helps.
  8. M Gray

    M Gray New Member

    Yes, thank you
  9. jetrock

    jetrock Member

    Actually there isn't a single "most prototypical size." In HO scale, Code 100 is the most common but in terms of scale it is the equivalent of extremely heavy rail, on the order of 200-230 pound rail (real-world rail is rated in pounds per yard.) Code 83 is closer to common modern rail sizes in HO but still kind of big. Code 70 is seen in HO, most often with low-profile "Proto:87" wheelsets with shallow flanges, but even well-tuned RP-25 (regular HO scale) wheelsets will work on Code 70 track.

    Code 100 and Code 83 track are seen in O narrow gauge (On30, On3 etc) because O scale is roughly twice as big--that superheavy 220 pound Code 100 is now 100 pound track (moderate sized) in O narrow gauge, and Code 83 is now very lightweight-seeming. Narrow gauge lines tended to use the lightest track possible.

    In N scale and narrow gauge HO, track gauges like 40, 55 and 60 play the same sort of roles as 70, 83 and 100 do in HO and narrow gauge O. In standard-gauge fine-scale O (as opposed to the toy-train three rail stuff) Code 125 and 156 are used, although Code 100 serves as light-duty rail sometimes on fine-scale O layouts.
  10. Triplex

    Triplex Active Member

    The general equivalence given is Code 100 = 156-lb rail, used only on portions of the PRR.

    From your other thread, I see you want to model the late 19th century. Rail was very light then - I don't know if even Code 55 is too big for 19th century HO standard gauge. This is one situation where it's difficult to get rail small enough.
  11. Russ Bellinis

    Russ Bellinis Active Member

    Code 55 is as small as you can go to my knowledge, but it is only available as flex track or rail for hand laying track. Micro Engineering makes code 55 flex track, but I don't know of anyone making switches, crossings, ar any other specialty track pieces in that size. That isn't a problem if you are ready to do some hand laying. If you want to lay ready made track, the smallest you can go would be Micro Engineering code 70, and there the only turn outs offered are #6 I think. If you need a full spectrum of choices for track sections, the smallest you can get is code 83.
  12. pgandw

    pgandw Active Member

    Shinohara made/makes(?) an extensive line of code 70 flex track and turnouts in both HO and HOn3. Don't know if it's still in production or not.

    Code 40 rail represents 40# rail in HO, and is suitable for 1860s and 1870s main line, and certainly for branch line and logging use in the later part of the 19th century. Micro Engineering makes code 40 flex track in HOn3, but their HOn3 turnouts (#6 only) are code 55. Code 40 rail can be spiked using scale size spikes from Proto:87 stores and still clear RP-25 flanges. And of course, any rail size can be used in glued or soldered track laying.

    I'd love to see a rail size between code 40 and 55 - something that represents the commonly used 60# rail in HO. Such a rail size would also be very useful in N, as well.

    my thoughts, your choices
  13. Omaha Road Man

    Omaha Road Man New Member

    Often times I read about modelers using different sizes of rail on different parts of their layouts to more closely model the prototype, code 70 on sidings, code 83 on mains for example. I'm assuming that in order to make transistions between these different rail hieghts smooth you'd shim under the ties to make the tops of the rails even?
  14. pgandw

    pgandw Active Member

    I sand the ties, but the theory is the same as the shims. But just using different size rail doesn't necessarily show the differences between main and branch line track. In fact, a lot of the model rail available has the same thickness in the head regardless of code (which only specifies rail height), so that if you are looking straight down on the track instead of across, you cannot tell the difference by the rail alone.

    On the prototype, sidings are typically graded at a slightly lower level than the main. In addition to the rail being smaller, ballast and ties will not be quite as good as on the main. These subtle differences are often how I spot a siding vs a section of double track on a line I'm not familiar with.

    In modeling these differences, viewing perspective empasizes certain details and de-emphasizes others. If you are looking at the track from near eye-level, rail and fill height are more prominent. OTOH, if you are looking down at the track, the ties, ballast, tie plate size, and rail head width become more prominent.

    just my thoughts, your choices
  15. Mountain Man

    Mountain Man Active Member

    And fter all of that, the whole thing is still highly illogical in the prototype world.

    Allegedly, lesser used lines warrant less expense, but since the same weight of locos and rolling stock will be running over those lighter rails...hmm. :rolleyes:

    In the narrow gauge world of the late 19th century, it made absolutely no sense whatsoever, as the sidings frequently led to mines from which the return trains, full ore cars at that, weighed every bit as much as any train running mainline. In the old photos of the time, you can see the effects on the lighter sidings and branch lines as they took quite a beating, especially as they were often ballasted with local dirt to save time and money.

    As for turnouts, it's a problem, because for mountain narrow gauge a #4 is protypical for sidings and branch lines, where space was often at a premium and didn't allow for longer easements or transitions. Again, you can easily see the abruptness of the turnouts in old photos. A #5 would be encountered only at a mainline junction, and none of the narrow gaugers ever went fast enough to need a #6 or higher. Average speed was often 20mph or less.

    An even bigger problem is just finding wyes in whatever code you are looking for in narrow gauge, as the ever-popular turntable largely did not exist at all in mountain narrow gauge railroading. By far the most likely turnaround was the common wye, present virtually everywhjere except in locations where large engine houses were present. On the 40 mile stretch of the Florence & Cripple Creek RR, there was one at Florence, one midway around Adelaide to allow turning helper engines, and up to seven or eight in Cripple Creek and surrounding environs, served at its peak by no less than six railroads - four narrow gauge and two standard gauge - and one trolley car line. Not a roundhouse or a turntable in the whole bunch, with the exception of the extraordinary trackage at Corkscrew Gulch. In fact. the wye at Anaconda, midway between Victor and Cripple Creek, is still in use by the 2 foot gauge tourist train, the only working two footer anywhere around.
  16. 60103

    60103 Pooh Bah

    AFAIK, all train set track is code 100. It makes a sturdier section of track for younger users.
    When I was starting, code 70 was quite recent. One article warned that many pieces of thsi "very fine section rail" were coming twisted lengthwise. You were warned to inspect it before laying (or buying). I still have a switch (rails only) that I made at this time.
    Anyone wanting smaller rail probably used brass strip, rectangular section.
    Remember that then TT was the smallest scale and they used a funny rail section with a keel on the bottom that went into a slot cut in the tie strip.
    On my layout I use code 100 and code 75 (Peco) and some bits of British scale rail. I don't have any problems with the code 75 except for some very old British stock (i.e. pre-1970) which does run along the spikes.
    If you want the other extreme, I have some Tri-Ang track with code 125 rail. (Not in current use).
  17. pgandw

    pgandw Active Member

    Not quite as illogical as you make out. Weight on wheels, thrust on curves, and joints and gaps at turnouts all caused faster rail wear. But the most important wear factor was speed of steam locomotives and trains. Until the 1920s, balancing steam locomotive side and drive rods was crude at best. Which is why steam locomotives' top speeds in MPH were generally restricted to their driver diameter in inches (or less!). When speeds were too high the drive rods would pound kinks into the rail every revolution, as well as trying to tear the engine apart.

    Also, dynamic equations often have a velocity squared term, where doubling the speed of a given train weight would cause 4 times the wear.

    But rail was very expensive compared to labor in the 19th century. In the 1860s and 1870s, British steel was considered to be quite superior to American, and the railroads would import their rail when possible depsite the extra cost. Congress was pressured into requiring use of US rail on land grant railroads. Even then, most rail was transported from the East around Cape Horn to a West Coast port, and then by rail to where needed. Using lighter rail where feasible preserved precious capital for other needs. If speeds were kept slow, the lighter rail would have a reasonable life span on less frequently used track.

    just my thoughts
  18. CCT70

    CCT70 Member

    I use code 83 on my main line, code 70 on sidings and code 55 on yard and spur tracks and never have an issue with flanges bottoming out, unless I run an old Rivarossi steam engine or my Bachmann 4-8-4 GS-4. Mine is a mix of handlaid and Micro Engineering Flex track.
  19. Here's one for you all, same subject:

    For a Rivarossi Big Boy engine that DOES NOT have RP-25 flanges (I think it has 18 or 16) what track would be best?
  20. CCT70

    CCT70 Member

    For THAT little monster, I'd go with Code 100.

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