Does anyone know if there are regulations on real narrow gauge railways about how heavy track has to be to be used on a passenger carrying railway? I might need to know for my next layout, which will feature light industry and a narrow gauge tramway.
There is no specific regulation, but it has to be of sufficient railweight to support the axle load of the coaches used. The weight of rail used has also increased noticeably in recent years. This is partly due to the lack of availability of small section rail but also because a heavier weight rail requires less maintenance. Labour to do this has gotten more expensive over the years and it's now cheaper to lay more expensive rail to begin with.
If you are only running a converted skip to haul a few workmen you can get away with rail in the 14lb-20lb range. Most old time passenger carrying lines would have rail in the 30-40 lb range with 65 lb being more common on 3ft gauge lines. Most current lines of any length will use rail from 60 lb per yard upwards these days.
Peco rail is code 90 I think which scales out at about 110 lb per yard in OO !
Old (Pre-1895) narrow gauge railways often had the minimum rail weight set out in their authorizing Act of Parliament. Gravity lines had heavier rail section than loco hauled ones because the lighter rails (deforming under each axle load) gave more rolling resistance. Hence the Festiniog was laid with very substantial track that was negotiable by Simplex 20 years after abandonment.
The Lynton & Barnstaple Railway, by contrast was laid with quite light rail be comparison, and was worn out to a dangerous degree by the time of (and was the major cause for) closure. It was not appreciated in the 1890s that the stresses transmitted to the track by the outside framed locos, with three closely spaced power axles, driven by outside cranks, and by the heavy outside framed and sprung coach bogies. The much maligned Baldwin, Lyn, was least damaging to the track, but tended to jump off the rails at the worn spots. Presumably the Baldwin designers were used to more extempory track arrangements.
By contrast the Leek & Manifold was laid with very light rail, but E R Calthrop specified very low axle weights for his locos and stock. It is very surprising to note that the railway managed its entire, albeit brief, existence with only two locomotives, both of which were in good order right up to closure.
On the modelling side, one would have to use 2mm Society rail, which might well be oversize, but of course, it couldn't accommodate the massively overscale flanges and tolerances of a proprietory chassis.
Paul
Quote from: tebee on July 28, 2012, 00:09
Peco rail is code 90 I think which scales out at about 110 lb per yard in OO !
Code 80 I think... Many lines have mixed weights of rail, I know the Welshpool have some points made from SG rail and also some of their original light stuff in the sidings...
With most old lines where the preservation group took over the rail used tends to be a mixture, with "new" lines then the weight tends to be the best they can afford at the time of laying!
Same applies to modern private lines, the JHMD has some newly relayed track at one of the terminii that is the spitting image of Tillig HOe track!!