# Track Centers



## doublereefed (Jan 3, 2008)

Folks, what's the current thinking on the correct dimensions for track centers so that large equipment (K27s and 7/8ths locos) can pass?

Thanks,

-Richard


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## steam5 (Jun 22, 2008)

Richard 

This hread may help 

http://www.mylargescale.com/tabid/56/afv/topic/aff/9/aft/112663/Default.aspx 

Alan


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## Dr Rivet (Jan 5, 2008)

Richard 

What is the radius of your parallel curves? 

Assuming at least 10 foot RADIUS on the inside curve, 9in may be required for Maine 2 ft in 7/8ths, if the curves are wider you may get by with 8-8.5 inches. I have 7.5 inch centers BUT I have 20 foot minimum RADIUS curves. 7 inches is NOT good enough, 7.5 is the ABSOLUTE safe minimum even on straights for 7/8n2 Maine equipment. 

Based on experience I would use 9 inches if you have the space.


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## jfrank (Jan 2, 2008)

Posted By Dr Rivet on 05 Nov 2012 06:26 PM 
Richard 

What is the radius of your parallel curves? 

Assuming at least 10 foot RADIUS on the inside curve, 9in may be required for Maine 2 ft in 7/8ths, if the curves are wider you may get by with 8-8.5 inches. I have 7.5 inch centers BUT I have 20 foot minimum RADIUS curves. 7 inches is NOT good enough, 7.5 is the ABSOLUTE safe minimum even on straights for 7/8n2 Maine equipment. 

Based on experience I would use 9 inches if you have the space. 

I agree with Jim. On our club track which has twenty foot radius we use 8" centers. I use 9" on my home railroad which is 1:20.3 scale narrow gauge. I would not use less than 8" on anything.


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## Ron Hill (Sep 25, 2008)

I have 8 foot radius' on my layout and I use 8" centers. I run 1:29 scale equipment and it works very well. 
Ron


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## SD90WLMT (Feb 16, 2010)

using 8 in. centers insures room for non-scale human cranes to move cars around with out tossing other trains off a near-by track.. even using a 45 foot min. radius system for a main line! 1/29 on the mains here. & 1/20.3 have their own world to run in. For 1/20.3 I run a 10 in. spacing....

Dirk - DMS Ry. 
http://dmsry.blogspot.com/


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## Dr Rivet (Jan 5, 2008)

Ron 

The question posed specifically addresses equipment MUCH wider than 1:29 standard gauge stuff. 
Most 7/8n2 Maine equipment cannot even operate on 8 foot radius because the equipment is too long. Two Bachmann or Accucraft K-27s, one on 8 ft radius would require a minimum of at least 10 inches center-to-center not to scrape each other.


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## doublereefed (Jan 3, 2008)

Jim, John, all! Thanks. A few of us are doing some early stage planning for a G1 live steam track at LALS. It sounds like we should go with 10" centers in order to plan for the future. It seems like every larger equipment will be running the rails... 

We will be using a minimum of 20' radii so that helps of course. 

Thanks! 

-Richard


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## Greg Elmassian (Jan 3, 2008)

Yes, I have 9 inch centers on mainline, wider on 10 food dia curves. There's even some 1:29 that this is tight with (Aristo RDC) 

BUT, as Jim rightly points out, the question is about K-27 (1.20.3) and 7/8 scale... MUCH larger. 

We are not helping a bit giving our 1:29 experiences, unfortunately. 

Greg


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## NTCGRR (Jan 2, 2008)

8 to 9" is best, all my tunnels and bridges was tested with K-27s and gunderson dbl stacks.


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## SD90WLMT (Feb 16, 2010)

And stuff a K-27 clears... 

A K-36 will HIT.... 

:`} 

And the new autoracks are to be taller than a dbl stack car and load..?? no confirmation yet on this tho....


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## Greg Elmassian (Jan 3, 2008)

The Aristo RDC has more "swing" than the double stacks... I can testify to that. Bought one and it was fine... but the RDC hit the tunnel portal. 

Greg


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