Another track centers question

[NW Modeling List]

Thanks Grant.  I appreciate the information. 

Also thanks to everyone posting the RMC updates.  For years I have been getting most of my information from printed publications.  It still isn't clear to me how those will be replaced with on-line publications or what those on-line sites are; if they are out there already.  I have seen a lot of stuff on youtube and some sites, but to me they don't quite come up to the level of the edited articles that are in the magazines. 

I find that it takes a lot more time to surf the net and filter the good from the bad on line.  Though I also suppose a lot of questionable information has been passed through the hobby publications over the years.

I am one that appreciates what editors have to do.  But I have also recently noticed that printed publications are starting to suffer in editing.  It used to be a point of pride in newspapers to get grammar and spelling correctly, but it seems like I am seeing an ever increasing number of mistakes.

I guess it comes from being old.

Bob Huston


---- NW Modeling List <nw-modeling-list at nwhs.org> wrote: 
> In inches, for 1.5" (1:8) scale, K = 1000
> 
> For Z scale, K is the same as in N scale, as any difference gets lost in 
> rounding error.
> 
> K only varies with scale, so any (narrow) gauge of the same scale would 
> have the same value of K. The reverse is true for G; it has several 
> scales for one gauge. For some context, this formula was derived from 
> the prototype for determining main line track centers on curves, 
> allowing for smokebox overhang. Other factors affecting centers may 
> apply in G gauge and narrow gauge, and for tracks other than main line 
> in any scale. For example, yard track centers might vary to allow more 
> room for carmen. Ladder tracks, particularly parallel ladders, need 
> wider spacing, but this too is driven by smokebox overhang on curves (in 
> turnouts).
> 
> Grant Carpenter

snip



> >> For track centers on curves:
> >>
> >> TCc = TCt + (K / R)
> >>
> >> should work for different scales and units of measure by scaling the term "K".
> >>
> >> For all terms in millimeters:
> >>
> >> TT3 (1:101.6) scale, K = 4300 [corrected from previous post]
> >>
> >> TT (1:120) scale, K = 3000
> >>
> >> For all terms in inches:
> >>
> >> N (1:160) scale, K = 3
> >>
> >> TT (1:120) scale, K = 5
> >>
> >> HO (1:87) scale, K = 9
> >>
> >> S (1:64) scale, K = 17
> >>
> >> O (1:48) scale, K = 30
> >>
> >> A disclaimer. . .
> >> I have only tested this empirically in HO scale. Your results may vary with scale and tolerances of wheel gauge, track gauge, track centers, and overhang.
> >>
> >>
> >> Grant Carpenter
> >> ---
> >>      Main track centers on tangent (TCt) were 13' apart, later 14' (post-war) and wider in curves. For track centers on curves (TCc) in British TT (3mm) scale, try TCc = TCt + (5000 / R), where R is the inside track radius (all terms in millimeters).
> >>