As a rule I give myself about 8" center to center on straight runs. Curves is a whole different beast and will vary based upon your rolling stock. Obviously, a forty foot box car will have far less inner hang than say, a heavyweight passenger car. Knowing what you are running on which track and how much the cars hang over between them is helpful. If you are planning 8' minimum radius curves (that's 16' diameter), then the eight inch spacing may work just fine for you in the curves, however, if you meant to say 8' diameter (which is 4' radius) then I would recommend a 10' diameter on the outside track. That should be sufficient for pretty much anything to pass alongside anything else in the curve.
Mark
The above is 11.5 / 10 / 9 ft diameter, the car's are aristo baggage and aristo smoth side coach hope this helps
The head is gray, hands don't work , back is weak, legs give out, eyes are gone, money go's and my wife still love's Me.
Tom Trigg
Tom, I should be able to post some new pictures of installed 10/11.5 Diam. track in the next week or so. My spacing averages 9 inchs on the curves and 8 inch's on the straights. BTY I am only using Aristo wide (10'diam) switch's and if you add a complete section of 11.5 your spacing will be about 8.5" on the parrell straight section.I will include a shot with the rest of the pictures.
This is what the 11.5/10 ft diam looks like
Age is only a state of mind, keep the mind active and enjoy life
Laying straight track is the easest. place a section of track along side each other and place any piece of equiptment on each. If you like what your see as seperation use it.
Yes as soon as you place a curve into your layout you start pulling your hair out.
You have to consider over and under hang. You also have to allow when you run a Challanger or Big Boy for there outcroping.
Also if you track is not perfectly level and solid. You have equiptment sway to consider.
Also you might want to consider easyment curves. The last portion of your curve is twice the radius of your curve. Flex track is great for that portion.
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