I did a test for the new DNRR ( indoor) the outer loop is 11.5ft Dia, the middel is 10ft the inner is 9ft. Spacing is 11.5>10 9inch centers 10>9 6inch. 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.
In a rare show of unity i agree with everyone that it isn't that simple; the problem is overhang both sideways and each end. My Mallet for instance is really a mongrel going backwards as far as overhang is concerned, forward its bad enough though.
It is no good saying oh you must have this spacing or that spacing; form where; here is a set of paramteres i have set myself and i have much track running side by side.
110 mm (4.33") width for a single track plus 40 mm (1.6") from the outside of the sleepers (ties) on either side for clearance from any verticle surface.
300 mm (1') for twin tracks and this will allow for sufficient clearance but if you are at all worried 20 (1") mm from the outside of the sleepers.
Rgds Ian
As Mark and Vic said, it depends.
This is a question with no defined answer, and is not scale-specific.
In 2-rail "0", on a club-sized layout, I took it upon myself once to mark clearance points on sidings and spurs.
Took out an SP AC-9 (normally-aspirated cab-forward) and the longets heavyweight I could find, for innerhang and overhang.
That was about 15 years ago, and the marks are still in use today.
You have to actually LAY track and see what the overhang and innerhang is on the equipment you use.
I recall Lionel aluminum passenger cars in the early 50's.....seeing them in a hobby shop window parked on 027 curves.....and all three rails were visible BESIDE the car.
And, if you are building to ONE engine and ONE car for inner and over hang, forget about new purchases.
When the CCRy was built 15 years ago, w made things extra wide and broad.
6-1/2 to 7" passing track centers, 6'8" radius....today that is somewhat limiting.
My Gallows Armstrongs are 6" between the uprights.
Outside valve body K-27's are wider at the valve body than that.
TOC
Have fun with your trains
I've used 6" as my guide for straight runs. Curves are a whole different demon. You have to base them on the type of rolling stock you run or are planning to run as well as the diameter of the curve. For example, a heavyweight passenger car going through an 8' diameter curve will overhang inside the curve far more significantly than if it were going around a 20' diameter curve.
It is a rare "G" layout that gets to enjoy the long graceful curves of a 1:1 train or even those of an HO or N. Most of us just don't own that much property, thusly we have to make compromises.
As for running along the wall, 3" on straights and 4" on outside curves. Inside curves follow the same criteria that would be used for running alonside another track.
mark
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