If you know me, you might be aware that I do tend to change my plans (Collingwood was originally hooked shaped!) and Bryn y Brenin Mawr is no different.
Actually, this change was brought on partly by an IT failure, the CAD plan on the introduction post became corrupted, so I had to re-draw it, but this made me think about the changes I could make it.
The second reason for the change was that I wanted to spin the standard gauge station around so that waiting shelter and platform face could be seen. Sadly I couldn’t do this as I simply didn’t have space (I know this sounds a bit weird and counter-intuitive, but it’s true), but I looked for ways to at least allow me to see into the waiting shelter.
So, starting with the existing AnyRail Plan of the layout seen above, I thought about what I ideally wanted from the layout:
Standard Gauge:
- Ideally, allow for a 4-Car Class 158 to be fully platformed (bit odd considering my fiddle yard will only be 3-cars long, but us Signal Engineers always look for passive provision’!), but 2-Cars will be fine
- A run-round facility to allow a Class 37 to run round a pair of RHTT wagons
- Long enough platform to allow said Class 37 to be released around a 2-Car Class 158 in the Platform
- Siding to stable single Class 37.
- Enough standage such that trains will not be stood over E.T.C.S. Balises
- Enough ‘plain line’ to allow some scenery, such that a 2-Car Class 158 could stand in the scenery between the fiddle yard entrance and platform protecting ‘Block Marker’
Narrow Gauge:
- Platform long enough for top & tailed 5-coach train, based on Peco L&B Coaches
- Carriage sheds to house said 5-coach train
- Ideally, facilities to house / stable 2 small steam locos and 1 diesel
- Turntable to turn small steam loco
Generic Scenery:
- Narrow Gauge to weave underneath standard gauge
- Able to see into Standard Gauge Waiting Shelter
- Not too much differential in height so that I don’t have to model large slate retaining walls (i.e., embankments can’t be that steep!)
So, this is the plan I came up with:
It is not too much different from the first one here, with the bulk of the changes being on the Narrow Gauge system, with the engine shed now moved down and served off the carriage shed, and a new turntable in place of the engine shed. The major change on the Standard Gauge was the addition of a siding off the run round loop to stable a loco
What has helped is now I know what baseboards I have to work with, I knew that I was going to use Tim Horn Baseboards and the maximum length was to be 9ft, so one 5ft long and one 4ft board, when I ordered them I said to Tim I wasn’t bothered about which end (as the layout was to be provided with a built in viewing window, so there was a R/H and a L/H end!) was which length.
Now that I have the boards at home, I could see that the L/H end was the 5ft end. I discovered that this would be very helpful in allowing me to lengthen the station area. The length in the original design was constrained by the need to keep points one side of the baseboard join and allow me to flexible on each end was 5ft!
To know how long the platform had to be, I needed to know three things
- Train Length (and length needed for Buffer Stops etc)
- The Clearance Point of the Crossover
- Position of E.T.C.S. Balises
Now, I know the train lengths as I have the 158 and a 37 to measure.
The Clearance Points are a little bit of guess work, but having printed out the layout 1:1 before and get the trains out, I determined that the CP of the points is 250mm from the toes.
From there, I could work out where the E.T.C.S. Block Markers and Balises would go, I don’t want to go into too much detail as yet, but I decided to compress the distant a little and have the block markers a scale 2m from the CP, then the balises 2m on approach to them and with a spacing of 2m. From there I could work out much platform I needed.
Sadly I didn’t have quite enough room to fit a 4-Car in the platform and allow for standage, but I’m not too fussed by that.
The Waiting shelter has been relocated to sit side on facing down the line right at the end of the platform, I can imagine that this would be a good spot for spotters!. It also provides a plausible access point to the stabling siding.
The narrow gauge portion of the layout threw up a little more complexity. I wanted to incorporate a turntable in the original design, but the only commercial 9mm gauge turn table I could find was the PECO N Gauge one which was far too large. But thinking about it, I realised I could get a small 100mm diameter turntable where the engine shed was. This would be large enough to turn the Bachmann Baldwin or Mainline Hunslets, but wouldn’t allow large locos (if someone does a WHR NGG16, I will get one!) to be turned, which is fine and adds interest.
The larger problem was where to fit the engine shed as I could get the clearance around the table in any other position than where the engine shed was in the original plan. I eventually twigged I could close the 6ft between the platform and run round roads (again due to the fact I could be sure where the base board join was). This gave me space to fit in an engine shed off the carriage line.
When I printed the plan one to one scale, and put on the buildings, the office building and the engine shed seemed to block too much of the platform line:
So, I decided to remove the office building and move the engine shed along a bit:
With the engine shed in place, this caused a smaller problem, it reduced the amount of carriage storage to allow for a ‘headshunt’ outside of the shed. However, I realised that I could still get cover for 5 coaches split over the two roads, it would just have to be a custom built carriage shed.
I’ve thought about this and quite like the idea of a custom semi-open wood & slate shed a bit like the station shed on the Corris Railway.
The next thing I had to do was do a little checking on vertical clearances…
What the plan doesn’t show is that the Narrow Gauge slopes down from the last point in the station to the fiddle yard and the Standard Gauge slopes up from the station to the fiddle yard. This is so that the height differential at the station isn’t too large to avoid those slate retaining walls!
What I needed to check was what height each level need to be at to not only obtain a 45mm clearance underneath the bridge (+ room for the structure of the bridge) to allow the narrow gauge locos underneath the standard gauge, but also to ensure that the gradients required weren’t too steep
As I could draw out the layout in 1 to 1 scale in CAD, it was relative easy and settled on the Narrow Gage being at 10mm from baseboard height and the standard gauge being at 60mm from baseboard height, meaning that both would have a roughly 1 in 100 gradient.
Now I can go away and CAD up the bridge to be 3D Printed, as this is the major structure needed as part of building the actual structure of the layout.
Talking of 3D Printing, I’m also planning on designing the Turntable to be printed (unless some knows of a commercially available, kit or otherwise, 100m diameter OO9 turntable) and the Carriage Shed.
Model Railway Signalling.blog 