I would use the track gauge that you feel looks right. I’m not familiar with the Code 100 NMRA standards. To tell you the truth, I have used code 70 and code 83 track on my layouts for 15 years and have no trouble with either one. Code 100 may be a bit more “bullet proof”, but if you spend adequate time laying your track, checking gauge and filing rough spots where you may have cut the track for instance, you should have no problem.
Thus, I would choose a gauge and manufacturer whose track looks good to you. Good luck.
First thing, relax! The truth is, fine HO layouts have been built with C70, C75, C83, and C100. Mr. Barrow has a particular vested interest in justifying his continued use of C100, but many other accomplished modelers use C83 from different manufacturers with good results. C100 might be slighty more robust, but if the selection of turnouts keeps you from doing what you want on the module itself, it may not be worth the restrictions in geometry. (On the other hand, a lot can also be done with C100 turnouts cleverly combined)
Note also that some more-flexible modular approaches like Free-Mo call for C83 HO rail.
Many (probably most) modular groups allow the use of different code track within the module itself as long as the interface tracks match their specifications. If there is a particular modular group that you are interested in joining, ask them about their specifications and recommendations. If you have no idea what group you will be joining, you’ll probably want to make the decision that suits your current situation best. One reasonable compromise might be C83 on the module itself and a transition to C100 at the interfaces, or C100 on the modular “mains” transitioning to C83 elsewhere on the module.
And if you are not planning to join a modular group, there’s no reason to follow the NMRA or any other standards. There’s nothing inherently “better” about modular standards. But it is nice to have the flexibility to join a group someday, if you think that’s a possibility for you.
Two 6-foot modules might be easier to move and store in the long run than one 8-footer, if you have room for the two 6-footers now.
I just looked at the NMRA Recommended Practices and there it is in black and white. I’m not sure why they recommend Code 100 for HO. Maybe someone else can comment on that.
I did a search on “Code 83” in this forum. There are over 300 entries - you can look for yourself. I looked at the four-line summaries of about 20 of them. Consensus seems to agree with the above comments. Many of the threads concern transition from one type to the other.
I’m using Code 83 now simply because IMHO it “looks” better than Code 100. I think my brass track in the 1950s was Code 100, but that’s too long ago to remember for sure, and I don’t have any pieces any more.
I am not familiar with any NMRA standard or Recommended Practice which omits code 83 for turnouts. But not to worry. Track and turnouts from any of the well known manufacturers (Atlas, Peco, Micro Engineering, Model Power, Bachmann, Walthers and others) will work just fine. You can mix manufacturers, buying your turnouts from one maker and your track from another. Was it me, I’d use the same size rail for turnouts as well as just plain track. In other words, I’d buy 83 turnouts to go with code 83 track, or Code 100 turnouts to go with code 100 track. This isn’t mandatory, you actually can mix rail size, but it takes extra care to join different rail sizes without a bump.
I did my layout in code 100 track for economic reasons, namely the club kindly let me have quite a bit of code 100 flextrack for free. Depending upon your budget you might want to consider code 100, it’s a little bit cheaper, and more likely to be available used. If you paint the rails of code 100 a rail brown, the rail looks considerable smaller than it does when it’s bright nickel silver.
I notice you are planning a 2 * 8 layout. You might consider making it a bit wider, to permit continuous running with a main line loop. The tightest HO curve is 18" radius, which means you need 36" (plus a skosh) to lay a 180 degree curve, which you need to form a loop of track.
Because the NMRA Standards and Recommended Practices were written 50 years ago when Atlas Snap Track was code 100 rail and was the cheapest one available.
A careful review of NMRA S8 and RP15 comfirmed what I thought. The NMRA makes no recommendation regarding rail size, in fact, the chart in RP15 gives recommendations for deminsions for codes 100, 83, 70 and so on, with no reference to scale.
Few if any of the comercial turnouts match NMRA standards or practices exactly. But most are more than close enough for good operation with NMRA RP25 wheels.
NMRA standards and RP’s set or suggest standards for gauge, flangeways and a host of related deminsions, but no asignment of rail size is noted for a particular scale/gauge.
Personally I use Atlas code 83 and am very happy with it.
I was not familair with the Free-Mo web site. It has destroyed all of my preconceptions about NMRA standards for module building. It basically has said to me “to heck” with your preconceived ideas. Thanks for sharing the site. What advantages on this site would I experience by registering on the site? What do you think?
Not sure but I think registering may give some more access, it does allow you to input information and such if you have a Free-Mo group and you want to announce events and such.
Someone said in an earlier post that you can do whatever you want as long as the interface is correct. That is not correct, standards are standards, if it calls for 100, then 100 it must be. Free-Mo is very strict, C83 on the mainline, and 83, 70 or 55 on sidings, absolutely no C100 anywhere, anytime.
I’m part of a Free-Mo group in Kansas and I can say that it is a very good modular standard. It allows for any number of configurations and leands itself to realistic operations.
Here are some pics from our last set-up last week in Wichita.