code of track?

Discussion in 'FAQs' started by TrainClown, Apr 22, 2003.

  1. TrainClown

    TrainClown Member

    :confused: Could someone please tell me what the differance is between code 83 and code 100 track is? and how codes work ?

    I would be greatful :)
  2. DanRaitz

    DanRaitz Member


    "Code" refers to the height of the rail in thousands-of-inch. Code-100 track is .100" tall, and code-83 is .083" tall. The taller the rail relates to heavier prototype rail. If you want to get more technical you should check the NMRA's site. Here is the link to their section on rail.

  3. shamus

    shamus Registered Member

    Hi TrainClown, Welcome to the gauge, Dan just beat me to it regarding the NMRA site.

    Have fun
  4. ezdays

    ezdays Out AZ way

    While we're on the subject, can anyone explain why for N scale:

    Atlas and Peco have code 80 and code55

    but Micro engineering and a few others have code 70 and code 55????

    I'm assuming that .010 difference is significant enough so that code 70 and code 80 tracks are not compatable.:eek:

    Aren't there standards? :confused:

  5. TrainClown

    TrainClown Member

    Thanks for the insight Dan. I looked at that web site, it's all greek to me. But thanks for the simple explanation.

    shamus! Your layout is perfect. I saw it befor when I was surfing the web but I never dreamed I would meet the modeler. I am humbled. Speatchless! (and the clown dose a prat fall):cool:
  6. jon-monon

    jon-monon Active Member

    EZ you can mix the codes just like the prototype mixes the weights of track; heavy track for mainline and light track for sidings. You just have to solder them so the top of the rails are even. HO has transition railjoiners I believe, but I dunno about N.
  7. Gary Pfeil

    Gary Pfeil Active Member

    Don, code 100 was the standard for HO for many years, code 70 was introduced a long time ago to give those who wanted a closer to scale rail that option. More recently (maybe 10 years already?) code 83 was brought about to more properly represent prototype rail from the (relatively) modern era. This all for HO. I am guessing that N track started out using the same rail sizes available already for HO, code 55 was also available at the time. The code 80 I think was introduced specifically for N scale. As Jon said, they can all be used if you are willing to do what is needed to make the rail tops even. I use (HO) code 83 for mains, 70 for passing sidings and yard tracks and 55 for industrial sidings. The appearance makes the effort worthwhile, at least to me.
  8. ezdays

    ezdays Out AZ way

    Hokey dokey, I got another question regarding track, not related to code though. I thought that the # given a turnout refered to the radius of the curved rails, with #6 being a tighter radius than a #4. I had a need for a tighter turn so I bought an Atlas 2705, #6 N scale thinking it was like an 9" radius rather than an 11" radius, but when I got it home, it had the same apparent radius as the 2701, #4 turn, only it was longer. Have I been mislead, or am I just confused?:confused:

  9. interurban

    interurban Active Member

    Hi Don I think the # difference is in the lenght of the switch which will give it a gentle swing i.e. for express line a longer switch as against a yard or slow branch line #4 will do.
  10. ezdays

    ezdays Out AZ way


    Thanks, but does anyone make a turnout that has a smaller radius? I could have sworn that I read in the MNRA literature that there was a difference in radius. I gotta look that back up.:rolleyes:

  11. 60103

    60103 Pooh Bah

    Peco have made a 9" radius switch in their settrack range. I don't know if it's still available.
    I think a #4 is bigger than 9" radius (In HO it's bigger than 18" -- probably about 24"/12"in N). and the bigger the number the bigger the radius. (And they're not really curved, so the radius is notional anyways.)
    Welcome on board. I remember when code 70 was new, and they warned that such a small rail tended to come through with some lengths twisted. (It was only available as rail, not as track :mad: ). Code 100 rail is designed so that if you put two pieces together with the bases touching, the resulting gap is a standard HO flangeway. I don't know if it works with other codes in other gauges.
  12. ezdays

    ezdays Out AZ way

    I checked the NMRA data and it says that a #4 is equivalent to a 18" curve, and #6 is equal to about a 22" one. I'm assuming that they are talking HO and that relates to N at about 9" and 11". Since my #4's appeared to be around 11", I assumed that a #6 was going to have a 9" radius. Wrong, I had that reversed, but even so, placing one on top of the other shows that they both have the same radius. How can I possibly be misinterpreting this? If two curves lay exactly one on top of the other, then they have to have the same radius or I wasted a lot of good bucks and time going to school.:rolleyes:

    D:confused: N
  13. 60103

    60103 Pooh Bah

    A numbered switch doesn't really have a radius. The frog is supposed to be straight, separating 1 unit in 4 or 6 or whatever.
    There will be a curved bit between the points and the frog; there may be a curved bit past the frog.
    Thew switch has two radii - the radius of the curved bit, which limits the equipment you can run, and a larger radius running through the whole curved bit, which would represent the circle if you made it out of 20 or 30 switches. :D
  14. RailRon

    RailRon Active Member

    EZ, the turnout number is simply a measure for the angle between the straight and the diverging track in a turnout. (It doesn't necessarily say something about the minimal curve radius in that turnout.)

    If you look at the sketch below: The angle of a #4 turnout is defined by measuring four units from the frog point and then one unit across the two rails. This angle is about 15°.
    If you would stretch out the base line to 6 units and then 1 unit across, the angle becomes smaller - about 9.5°. (Real 1:1 turnouts have frog numbers up to more than 25!)

    Now, when I understand you right, you are looking for a turnout with a very small radius. As far as I know there is such a turnout made by Minitrix, with an angle of 24° or 30°. That translates to a # 2 frog!!

    On my former N scale layout I used some of these turnouts for industrial sidings. As far as I remember I had no problems with derailments - but I can't speak for today's rolling stock. However, they look a little toylike.


    Attached Files:

  15. K.V.Div

    K.V.Div Member

    Peco's 9 inch radius settrack turnout is still available. A turnout's number is based on the number of "units" of straight track in relation to curve track starting at the "frog" of the turnout.
    The frog is the part where the two inner rails join together.
    For example: If a turnout extends 4 units of straight length on the inside rail from the frog and, at that point, the diverging inside rail is 1 identical unit of length from the straight rail, you have a #4 turnout.
    The Atlas #4 turnout has a 19" radius curve and I am not sure what radius of curve is on the #6 turnout.
    Atlas, Micro Engineering and Shinohara list their turnouts by number, while Peco lists them as Small, Medium and Large while their actual radius is listed in their cataloge.
    Peco's Setrack Turnout (Small) is 9 inch radius, while their streamline Turnouts are as follows:
    Medium: 18 inch
    Large: 36 inch
    Medium Radius "Y": 30 inch
    Curved Double Turnout: (Inside) 18 inch, (Outside) 36 inch.
    For their Code 55:
    Small: 12 inch
    Medium: 24 inch
    Large: 36 inch
    Medium Radius "Y": 24 inch
    Curved Double Turnout: (inside) 18 inch, (Outside) 36 inch.
    BTW, All these measurements are in N Scale
    Hope this helps and have a great day :cool:.

  16. ezdays

    ezdays Out AZ way

    Thanks David, thanks Ron, thanks Terry. I just might be getting it now. For someone who is use to reading technical data sheets, when all you find is "a #4 has a curve of 18 inches and a #6, has a curve of 22 inches" I immediately came to the conclusion that curve and radius were the same thing. A logical conclusion without more explaination or data.

    Yesterday, out of desparation, I just went ahead and added some foam here, cut some foam there, and was able to relocate the turnouts on sections of track that would work with the curves, :eek:uh, I mean radius of a #4... or was that a #6?:rolleyes: Well, anyway, I should find out today if it's OK. If not, I'll check out the Peco turnouts.

    Thanks again for the good data. If there was a reference section here, this would belong there.:)


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