Hello, For some reason my mind is blocked in getting the concept of John Armstrong Square which is mentioned in his book page 84 "Track Planning for realistic operation". I read it many times and read more about it on the Internet and still I do not get it. So could you please if you have time make this very easy for me like "Square for Dummies" and how can I relate this to my N scale for the attached layout. Thanks. Mo
Read his book couple years ago and can no longer get one to check, but think it is a way of transferring a drawing in any scale to the real layout area ... one could establish a virtual grid of squares on the real platform and then mark off key locations or landmarks to guide track laying or whatever ... just make sure that you know the scale relations of your plan to the real layout ... If that isn't what it is, then above is a good idea anyway ... :tb-biggrin:
I must have a different issue of that book, but basically that is his way of saying how much approximate space a given track plan will take up, depending on what scale (Z, N, HO, S, O, etc) you build it in, and the minimum radius of track curve used. So, depending on what the minimum radius is that you choose to use, the size of a "square" in N scale would be between 13 inches and 20 inches on a side (according to my edition of the book).
Yep, Rasputin's got it ... thanks A way of relating track plans across scale ... never was an issue for me, I guess
I will have to go look it up- I've got a couple of John Armstrong books stashed away under the layout. Meanwhile.... your post title gave me the idea of building a little model park called "John Armstrong Square."
Armstrong's square was defined as the minimum radius plus twice the track spacing. So if, for example, you were using 17 inches as your minimum radius, and 1.5-inch minimum spacing around curves (to allow for overhang), a square would be (17+1.5+1.5) = 20 inches on a side.
Call me a dummy..I think i will cheat and print out a full sized model of the track plan...whenever that will be.....:ru-wink:
The idea of the square is to let you quickly get a feel of what will fit in the space you have, given the minimum radius you intend to use. It lets you quicky, and without doing any detailed design, sketch out what kind of elements will (or, perhaps more importantly, won't) fit in your space. Using the squares method helps to reduce our tendency towards optimism, and thinking things wiill fit when there really isn't any way.
As stated its a quick and dirty way to figure out how much RR you can put in one area, it is primarliy concerned with turnback curves. Another rule of thumb I use is the "standard" benchwork width plus 1/2 the "standard" aisle width. If you think a "comfortable" RR has 2 ft wide benchwork and 4 ft aisles that is 2 + 2 or 4 square ft per linear ft of railroad. So if you have a 20x30 basement or 600 sq ft, I figure you will get about 150 ft of mainline run in the room. I usually come out pretty close.
