Need help on standards

[Chesticus]

Well this board helped on my last problem. I am dexigning a model RR. I am trying to find the proper/standard distance between track centers on a curve. You would think that would be easy to find, but I can't find it.

Help

Chesticus

[WoundedBear]

http://www.nmra.com/

Everything you need to know, all in one handy website.

Sid

[Chesticus]

I went there and I do not see anything relating to how far apart the centerline of tracks on a curve should be.

Chesticus

[JerryB]

Look here for center to center distances on various curves:

http://www.nmra.org/standards/s-8.html

and here for clearances on tangent track:

http://www.nmra.org/standards/s-7.html

Happy RRing,

Jerry

[Woody Elmore]

You could use an NMRA standards gauge. You can get one from Micromark or join the NMRA.

[SteamGene]

Woody,
I don't think they send a new member a Standards Gauge any longer.  I joined for the first time last year and didn't get one.
Gene

[JerryB]

The NMRA hasn't provided new members with a 'free' gauge for quite a few years.

There is a significant price difference between sources for the gauges. For an H0 gauge:

NMRA Member price: $5.00
NMRA Non-member price: $12.00
Micro-Mark: $18.50

Other sizes / scales have similar prices.

I think these gauges are a required tool for model RRing. I even have one for 1:20.3 scale / 45mm gauge.

Happy RRing,

Jerry

[Chesticus]

Thank you for all of the links you guys. I must have been pretty tired because I could not understand them at first. I was really frustrated. But I got it now. Thank you.

Chesticus

[Jim Banner]

A couple of things to keep in mind:
- The NMRA wheel and track gauge gives clearance for tangent (straight) track only.  Because of overhang, you will need more width on curves to prevent trains from sideswiping.
- If the tracks are at different levels, you will need more horizontal space between them to allow for scenery.  An extra half inch for every inch of vertical separation is a good compromise between prototypical correctness and the realities of never having as much space as we would like to have.  The exception would be in cities where vertical retaining walls may be built at great expense because land values are so high.

[ddellacca]

Jim,

I would never argue with you...., too much respect...
but NMRA RP S-8 does give the recommendations for
curvature separation, unless I'm mistaken.

Dick

[Woody Elmore]

Sorry - didn't mean to imply that the NMRA supplies free gauges.

I can't see how anyone could do a layout without an NMRA gauge. I can't list all the times I've had new trucks with out of gauge wheels or switches that weren't in gauge.

Unfortunately, we are in the era of RTR right out of the box and people assume that everything they buy is perfect.

[SteamGene]

I knew that NMRA USED to supply a "free" gauge with each new membership.   I just assumed you thought it still did.  If it did, I'd have three now.
Gene

[Jim Banner]

Dick, I agree with you 100%.  I mentioned the standards gauge only because Woody recommended it without mentioning that the clearance it gives is only for straight track.  S-8 is the way to go for curved tracks but it applies only if the tracks are in the same  horizontal plane.  I find that using the separation recommended by S-8 and adding 1/2" horizontally for each 1" of vertical separation allows room for scenery.  I guess I caused confusion by forgetting to mention that the "more than" referred to the S-8 separation.  Incidentally, this adding 1/2" horizontally for every inch of vertical separation works in all scales.  For example, if I had a 48" radius curved track in 1:29 G-scale and wanted a parallel track, I would use 55" radius track if both tracks were on the same level.  But if one were a foot higher than the other, I would add at least 6 more inches to the radius of the outside curve, giving 61" radius. 

[ddellacca]

Jim,

Just the way I took the NMRA information, also.
Good explanation.

Dick

[Loco Bill Canelos]

Some one above mentioned a guage for 1:20.3, but I could not find the info on the NMRA pages above.   Anyone know the source for 1:20.3, 1:22.5 & 1:29 .

Thanks