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design sizes

3213 Views 11 Replies 5 Participants Last post by  jk1
Hi, i am currently designing a new layout after being out of the hobby for a while and have forgotten a few things! Could someone let me know the width in "mm" centre to centre for a double track main line. Im using AutoCAD to just sketch up a few ideas and need to know spacing so i can see what my board sizes can take. I will probably be posting for design help soon aswell!

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I think that the prototypical double track centres scales at 45mm for OO. However, this is too close unless you are using really generous curves, say 1.2m radius or probably even larger. For this reason Peco make their points join for a crossover at nominally 50mm although I recently measured it to be nearer 52mm. Hornby and Peco settrack have something horrible - about 65mm.

You can adapt Peco points to give a closer separation. I recently reported, in another thread, that I have made mine 47mm which is OK for my 900mm minimum radius curves with my 60ft carriages. (Modern longer coaches would need a wider gap or more generous curves.)
The prototype distance is 6ft between the outer edges of the two adjacent rails of a pair of tracks - this distance therefore scales to 24mm in 00 terms. (This distance is a lot easier to measure than the distance between the (invisible) centre-line of each track.) This distance is about 32mm with Peco points which gives around 50mm centre-line to centre-line as Robert says.
Set-track is about 48mm between the adjacent rails, which is virtually double what it ought to be - but as the curves are so much smaller in radius than the prototype the extra width is needed to avoid coaches and locos colliding with each other as they pass.
John Webb
Ahh thankyou, that should help... now another question! The room i am going to build the layout in has central access stairs and has a couple of doors 2 an en-suite etc but the main room dimensions are 4.465m x 6.388m. I have to have a resonable sized bedroom in the middle and plan to go all the way around the outside. Having nice long running lengths i dont want to spoil things by having small radius curves in the corners. The base board is going to be on average 450mm wide. As i am going to be modelling modern image, whats the recomended smallest radius?

I would avoid a track plan that is rectangular, with curved corners.

for such a size, I would aim for, more or less, continuously-curved trackage..........this would allow you to avoid the 'jerk' 'tween straight and curve?

Imagine an elongated, 'waisted' oval?.......or even, an 'egg' shaped plan?

By limiting board [shelf?] width, this also saves on scenery?

Also, any minimal radius curve is more tolerable if you employ transitional curves on entry and not having to 'meet' a straight-line run of track, these transitions could be better accomodated.

Another 'advantage' of a gradual transition curve into your minimum radius is, that in fact, as the trains are ''led in'' to the tight curve, even a slightly smaller minimum radius curve could be employed.

you could employ minimum radii in excess of 1 to 1.5 meters?

lots of curved turnouts, though?
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Above is shown roughly baseboard wise i came up with. The section across the en-suite door etc is going to be covered, on top will be an 009 end - end section modelled on the new welsh highland railway. Please make alterations if you see fit! Any suggestions welcome

Walk in wardrobe is going to house all the electronic gubbins and my lenz set 100 boxes etc, i thought maybe i could have my self a small fuelling depot and would provide a switched dead section for easy addition and removal of trains without causing short circuit. This would be accessed by a small hole through wall as indicated.

Layout design wise, im looking for 3 lines, a double main and a branch, all three will loop but will alternate between visible and hidden by scenery etc to provide a realistic view.

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That's an impressive size available for the layout; I'm envious!

While, in principle, I agree with much of what Alastair says, I think that a continuously curved layout of that size would come a long way out in the corners. With that length available there is nothing wrong with a bit of straight down each side as long as you enter the corner curves very gently with as Alastair says long transistion curves. I would have a minimum radius of at least 1m but this for only 45 degrees of each corner. It will allow close coupling of coaches as a nice extra. As we discussed on another thread recently, transistion curves really separate the realistic model railway from those that are toy-like.

Also you might consider not packing in too much railway. I think that overcrowding also looks unrealistic. Your idea of a double track main line and a single track branch sounds really good and could be made to look very realistic in that size. Your space is large enough to take two stations but it depends on how much covered area you want for a fiddle yard. If you are going to run long express trains then you might need all of one side or one end.

Good luck; let us know how things progress.
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Junction to branch terminus?

with some intermediate staions?

all superimposed on a simple, double track mainline?

To be honest, although the dimensions were given, I didn't visualise just how much length was involved.
Note sure if you aware, but seeing your CAD drawings you may be interested in the program WinRail 8. It's a pc based layout planning program that includes libraries of the track from all the main manufacturers and allows layout planning by dragging and dropping items onto your design on layout boards. Layout boards, framing, track etc can all be on seperate layers and clicked on and off as required.

I have used it on number of occasions to design various layouts and found it to be easy to use and very accurate.

Have a look at the website WinRail 8. It costs £39.95 as a download.

There is also a Free Trial version to download to see what you think of it before you buy a copy
Will it allow transistion curves using flexitrack?

I wouldn't spend that sort of money on something I can do with paper and drawing instruments.
QUOTE (Robert Stokes @ 25 Oct 2007, 21:00) <{POST_SNAPBACK}>Will it allow transistion curves using flexitrack?

I wouldn't spend that sort of money on something I can do with paper and drawing instruments.

Yes it has a button for setting up transistion curves.

I could do all my layout work with paper and drawings instrutments as I used to be an Architectural Technican before the days of CAD, but this program is much more fun and it has various levels of undo, so you can try all sorts of things and if you don't like it, just click the undo button!
Thanks for your input, i always know what im looking for in my head but never really know how to make it look realistic when placing it on the baseboard. Ive always had tail chasing layouts before never being big enough to run long convincing trains, this should be a chance for some of my express loco's to stretch their legs rather than being sat in my display case! Being away from doing any modeling for a bit has been sparked by various visits to my local WSR (West Somerset Railway) and being a member of the Welsh Highland Project. I wish to try and include both 00 and 009 in a convincing way using modern image. Hopefully successfully running the modern mainline locos and steam narrow gauge locos without looking to fake.

The room has just been converted from a cider barn adjacent to our house and is being plastered on mon. As soon as its painted i will be starting the baseboard. I cant really deviate on baseboard sizes as the room has to be used as my bedroom, and for all that hard studying to get into architecture school! (Hopefully i wont get to distracted!)

If anyone has any layout design ideas please share!
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