S Gauge minimum radius

Discussion in 'Layout Design Discussion' started by Tyr, Oct 14, 2010.

  1. Tyr

    Tyr New Member

    Hi everybody, first post here. I'm laying out a train room for my 2 boys (ages 6 & 9), as well as myself. Around the ceiling, I'm putting up an around the room shelf layout w/ their 2 lionel OGauge trains. Along the floor, around the perimeter of the room, I wanted to add a layout the kids could actually play with. I first planned on putting in an OGauge switcher setup that would cover 3 of the four walls. The 027 turns were to be in two opposing corners of the room- to take up the least amount of space. Problem is, the o27 is taking up a little too much room (the rooms 9x9). I don't have anything against HO scale, but it may be too small for the 6 yr old. I also wanted some operating accessories to keep the kids interested. I'm now looking at S gauge. Can any of you tell me what the minimum turning radius is for S gauge? I also welcome more experienced opinions re: the setup as well and any kid friendly advice. Thanks, look forward to hearing from you.
  2. BoxcabE50

    BoxcabE50 Staff Member TrainBoard Supporter

    Welcome to TrainBoard!

    Will you be using tinplate/hi-rail type track? Or scale track? I believe we have talked about radius for American Flyer in here before. There might be something in the old message archives. Could be worth a try.

    Boxcab E50
  3. COverton

    COverton TrainBoard Supporter

    Have you consulted the NMRA website for their conventions for S Gauge? It is the National Model Railroad Association, in existence for donkey's years, and they have a pretty good handle on accepted standards and conventions on most of what helps our toy trains to run reliably.

    However, in any scale, the minimum radius of curvature is highly dependent on the design and engineering of the model you are going to run. In other words, and despite the claims that appear in the literature for each model, the 'coal face' test is what counts. There are HO 4-8-4's that will work well on 18" radius curves, "tight" curves in that scale, whereas there are others, notably brass and higher end, that are recommended to be used on nothing less than 22" and on up.

    I would hazard a guess, without looking it up, that a radius near 22" is going to be very tight, even unreliable in some cases, for S Scale.

    The thing to take away from this is that, no matter what I say or what the manufacturer says, the verdict is rendered only by your engine on your tracks the way you lay 'em.
  4. Tyr

    Tyr New Member

    Oh boy, I'm in over my head here. I'm not sure which track to use. Any suggestions? Any thoughts about HO for a 6yr old?
  5. BoxcabE50

    BoxcabE50 Staff Member TrainBoard Supporter

    HO would probably be OK. But why not "S"?

    The track differences I noted are between the old style American Flyer, which has about three big metal ties per section of "tinplate" rail, or track which looks a lot more like you see in HO or the real thing.

    There is a good web site to start from for S links and info:


    By all means, feel free to chat and ask questions here.

    Boxcab E50
  6. ratled

    ratled TrainBoard Supporter

    MRH had a great article on this in their 1st edition. It works for any scale and any era. It is based on the length of your rail cars. I don't remember it per se but it was something like 3 x length (ie car is 9" then 3X would be 27" radius) will work but look toy like, 4 X would be better and look better and 5 X is best. You can download that issue for free here http://model-railroad-hobbyist.com/mrh2009-01/download as they are forever free for all issues
  7. roadranger

    roadranger TrainBoard Member

  8. Greg Elems

    Greg Elems Staff Member

    O27 is 13.5 radius. SHS Helper has 20" radius in their starter sets with road bed like the Bachmann track. American Models has 21" radius on their brass track that looks like the old Atlas code 100 brass track. Everything SHS makes runs on their track. AM equipment should do fine on the SHS track also.
  9. BoxcabE50

    BoxcabE50 Staff Member TrainBoard Supporter


    Memory lapse tonight- What was the radius of AF track? Wasn't it twenty one inches? Making a forty two inch circle. I cannot dredge it from the old gray matter tonight... :tb-wacky:

    Boxcab E50
  10. Greg Elems

    Greg Elems Staff Member

    Boxcab E50, I sure don't recall AF's old track radius. Roadranger mentions 19" radius and that sounds right. I uses AF track on a layout once and it seemed to me that 19" radius is what it was but that was 26 yrs ago. Talk about the old gray matter........I do remember reading that the AM FP7 could run on the AF track but some filing may have to be done on the steps for trouble free truck rotation. I didn't want to do that so I went to Gargraves instead. Tomalco and Shinohara came out with flex some time in the mid 1980's and that is when I decided to go scale.

  11. markjs

    markjs New Member

    I believe that O27 is 27 inches diameter, not radius. American Flyer tinplate is 20 inch radius (more or less) and therefore 40 inch diameter.

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