Converting Track Plans to Different Scales

Model Railroader General Discussion (Model Railroader)
1

I was browsing through some track plans books today. Most of what interested me was either in O or N scale and I model HO. I remember reading somewhere that O is about 80% larger than HO? So I was taking the number of feet in the layout and multiplying by 12, then multiplying by 1.8 and dividing the answer by 12. Seems convoluted but using that, I came up with a 16 x 29 layout in O be approximately 9 x 16 in HO? Is that basically the way to convert? If yes, what is the multiplier for N? Thanks.

2

This might help: http://www.nmra.org/beginner/scale.html

So, for example, multiply each HO dimension by 0.54375 to convert from HO to N.

3

When converting track plans from one scale to another, there is one key fact to remember:

Models scale - people don’t.

Translation - that comfortable 30 inch HO aisleway shrivels down to 16 inches when reduced directly to N. Au contraire, if you convert an N-scale donut (central operating pit) to O scale, you’ll be able to park a pickup (or a peninsula) in the pit with room to spare.

When changing large-size layouts from one scale to another, make sure that the 1:1 scale operators will fit.

Chuck (modeling Central Japan in September, 1964)

4

Thanks very much, I’ll remember that. I’m one of those guys who needs most of a 24 inch aisle now. Mostly I’m just trying to ball park what ones in the book might fit in my planned area and what ones would need a lot of adjustment. I did look at the NMRA site that Phillip mentioned. That will help too. Thanks.

5

[emphasis added]

I don’t understand why you multiplied by 12 then divided by 12. [%-)] When you do that, the answer is as though you never multiplied or divided in the first place, as you can see below…

  • 100 x 12 = 1200 1200 x 1.8 = 2160 2160 / 12 = 180
  • 100 x 1.8 = 180

You can save yourself a whole lot of math if you just left out the multiplying-by-12 and dividing-by-12 calculations.

6

Yes, and factor #2 to keep in mind: models stay the same scale with age. Humans tend to get wider and wider (and less and less nimble when it comes to duckunders and the like). Plan for this, even if you don’t believe it can happen to you! As one of Model Railroader’s senior editors joked at an operating session, model railroaders already tend to “Exceed Plate C” as it is …

Dave Nelson

7

My current layout is modular. I have a lift-up bridge because I completely understand the duckunder problem.[;)]