THE RIGHT PLATFORM HEIGHT?
In the article ‘Model Wet Weather’, in the November 2018 issue of Model Rail, Chris Leigh writes: “The platform was then built up using an ‘egg box’ with a height of 25mm (20mm if you are not using track underlay)”.
My cork underlay is approximately 3mm high, so the top of the track is around 8mm above the baseboard when placed on the underlay; leaving a platform height above the track of 17mm if I use underlay and Chris’ suggested 25mm. I don’t know what Chris used for his platform surface, but this would have added more height to the platform.
I have commenced building my platform and was using an old Peco publication,
Starting in Scale 00, (third revised edition, 1968) as my guide. This has a diagram for ‘OO’ gauge standards which indicates that the platform height above the track should be 12mm.
I realise that I am questioning a matter of possibly 5mm but that is potentially a difference of more than one scale foot, or have the ‘OO’ gauge standards changed since 1968?
If I use a 19mm pine base, topped with 3mm balsa wood (totalling 22mm), it would create a platform height above the track of 14mm when the track is placed on underlay. Is this difference of an additional 2mm from the Peco publication diagram worth worrying about?
Ian Mcgregor, by e-mail
Chris says: You make an interesting point. It has much to do with what you use as your datum, the baseboard top, the track base level, or the rail top. The latter two will vary according to how/if you ballast your track and use underlay (which itself varies in thickness between different brands). Also, a Peco booklet from 1968 would be using BRMSB (British Railway Modelling Standards Bureau) specifications which were intended to bridge between train sets and scale modelling, so they would err on the ‘generous’ side with clearances. They would also have based their dimensions on railway practice at the time, when there was a lot of variation in platform heights with some rural stations having very low platforms. I live in an old station and I suspect that your 12mm (3ft) platform height would be about right but I also know that it would be quite a step up from my platform into, say, a Mk 1 carriage.
Over the years, platforms have become higher and the modern standard allows easier disabled access. Using Woodland Scenic’s track base under my track lifts it by several millimetres, and my ‘egg-box’ is mounted on the baseboard surface, so it needs to take account of the thickness of the underlay. I’ve found that 25mm verticals with a layer of 2mm mounting board brings my platform up to solebar level on a Bachmann or Hornby Mk 1.
You can, of course, model a platform that’s low if you’re modelling pre-1970s. At that point BR started raising low platforms. Heyford, in Oxfordshire, for instance, had a wooden ‘deck’ built, while rural stations had step boxes to assist passengers. Others had their platforms completely rebuilt
The important thing is to get a height that suits your layout and rolling stock, so I would suggest doing a bit of experimenting with card strips to see what looks right against your rolling stock and allows adequate clearances for operation.