Railroad-nerd question: concerning US gauge-changing project, 1886

Something hitherto unknown to me, recently come upon by chance in a MPSIMS thread from a few years ago – link to same, here.


I learn that over two consecutive days in 1886, per a very well-planned and -prepared-for programme, over 11,000 miles of railroad track in the south-east of the USA were converted from the track gauge of 5 feet – on which the majority of lines in the former Confederate States had been laid – to a slightly narrower gauge. (We in England feel very pleased with ourselves for having, a few years later, done a similar thing over a similar amount of time – re converting our last-remaining stretches on the extremely broad 7 feet gauge, to 4 feet 8-and-a-half inches standard gauge – which involved a little under 200 miles !)

There’s an issue to do with this feat – told of in one of the “links” led to by the linked thread – which seems strange to me. The basic reason for the gauge-change in the south-eastern US was to allow through running without trans-shipment, between the lines in the south-east; and those further north and west, which were (fairly) uniformly on the Standard 4 feet 8-and-a-half-inch gauge. There was, however, a complication. The extensive Pennsylvania Railroad, in the north, had a gauge fractionally greater than the above “Standard”: i.e., 4 feet 9 inches. The Convention of railroads serving the south-east, which put together the gauge-change project, decided to change to 4 feet 9 in., mostly because many of their railroads linked at their northern limits, with the Pennsylvania Railroad. There were dissentient voices in the Convention, urging a change to “4-feet-8-and-a-half”, not “4 feet 9”; but they were overruled – the mass alteration in 1886, was to 4 feet 9 inches. Modification of these lines from that, to 4 feet 8-and-a-half inches, took place gradually and bit-by-bit over the succeeding decades.

I’d be interested to hear from anyone well-informed about these matters, re this question: I assume that the half-inch difference in gauge was small enough, that it was possible in the main for freight cars at least, to be worked throughout the fractionally-different-gauge systems? If that had not been so; then all the planning, and frenzied work over the crucial two days, would surely have been pointless.

I would like to piggy-back on this - wouldn’t a (slightly) wider guage possibly result in the wheels “wobbling”? Those pivoting 4-wheel bogeys(?) would start oscillating at higher speed in a dangerous manner? Or were most rail cars back then still single-fixed-axle models?

I cant’ Imagine you could make the smaller gauge train work on the larger track, at all, given the loads carried by freight cars. But I’m not an expert.

Nah, the half-inch difference is not ideal but it still works. It only amounts to each rail being a quarter-inch off and the rails themselves are a little more than two and a half inches thick at the head. Eventually almost all rail in North America was standardized at 4’8.5" but that was a more gradual process.

I would think that the harder trick would be the squeeze of the 4’ 9" wheels into a space half an inch too narrow…

In Cincinnati the early street railway (horsecar) companies chose track gauges of either 5’-2" or 5’-3". There was fear in the city of street-running railroads, so they picked a gauge that was incompatible with the standard gauge (4’-8 1/2") and wide gauge (6’-0") railroads that were serving the city in the 1850s and 1860s. When the companies started to consolidate, they standardized on 5’-2 1/2" which worked fine. This had all settled out before the narrow gauge railroad fad of the 1870s introduced 3’-0" gauge tracks to the city. 7’-0" gauge is monstrous though, and I can only imagine the beast trains that ran on that sort of track.

Anyway, while horsecars weren’t the most rigidly engineered vehicles compared to later cable cars and streetcars, or even the rail cars of the time, it’s another data point that 1/2" is within tolerance. It’s not really a problem because the wheel flanges actually don’t touch the side of the rail (when going straight anyway). The slight curvature of the top of the rail and the conical shape of the wheels causes them to self-center without need for the flange, so there’s a bit of extra slop built-in. http://www.railway-technical.com/whlbog.shtml

The wheels ride on top of the rails. As long as there is enough clearance for the flange, it’s fine. And there’s going to be more than half an inch of play when going around curves, anyway. Trains are designed for some pretty generous tolerances in rail gauge.

Isn’t the consensus today that 4" 8 1/2" is too narrow for the much heavier loaded rail cars today? That a wider distance would be preferred but would be too expensive to do?

In answer to Past Tense, not exactly. A wider track gauge would be nice, but not really all that essential. Right now the 4-axle (2-truck) cars in mainline service can handle 268,000 lbs load, including the railcar itself. Some heavy duty lines can go 290,000 lbs on 4 axles. It’s just as easy to add axles, but not often is that much of an issue. Few things really weigh THAT much, most heavy things are commodities like coal or grain or oil, when you reach the weight limit of one car, you use two cars, etc to the 200-plus coal trains now in use.

Changing the rail (track) gauge would be not all that expensive (relatively), but the real limit is called the loading gauge, which is the clearance required to get thru tunnels, under bridges, past platforms and lineside structures, etc. That would be a REAL headache.

Our pioneering friends in the UK use the same track gauge we do, but our loading gauge is considerably larger, in both width and height. That is partly why their trains look smaller than ours, the equipment is narrower and shorter. A few years back there was an excursion railroad co starting up in England. They built a hundred and some cars and then went bankrupt. VIA rail canada bought them up cheap, and converted them to run on north american (brakes, couplers, and suchlike). They are now called the rennaisance (sp?) cars. When used here, the narrower cars need ramps to span the gap to our platforms.

Mind the gap.

I’d be interested to hear more about this. What’s an excursion railroad?

Thanks, folks, for the clarification. Reason was telling me that freight cars would have to be essentially workable throughout, notwithstanding the half-inch difference; otherwise (the Pennsylvania Railroad complication aside), the whole huge undertaking would have been futile – but it’s good to have confirmation !

In some circumstances, even a small difference in gauge can create difficulties. The continent of Europe has a number of local lines on a – very definitely narrow – gauge approximating to 2ft 6in. This comes in Europe, in two varieties: metric measurement, 75 centimetres (traditionally favoured in Germany and Russia); and 76 centimetres (used by the former Austro-Hungarian Empire). Attempts to run vehicles / motive power of one of these varieties of this gauge, on track of the other variety, have often failed to work well. The difference of one centimetre, is very close to half an inch. One suspects that the tendency for very-narrow-gauge gear to be smaller-scale and more delicate, than on gauges about twice the width; may make such a difference felt more on the former scene, than on the latter.

jjakucyk writes: “7’.0” gauge is monstrous though, and I can only imagine the beast trains that ran on that sort of track.”

In fact, from the photographs of Britain’s 7 ft. gauge (an example of same, linked to below)


the trains thereon did not look that grotesque: their proportions were relatively modest in the context of the gauge. There was a lively “gauge war” in the UK in the mid-19th century: the “7 ft.” had passionate proponents, who wished the whole country’s railways to be on said gauge. Given the technology of the time, the 7 ft. gauge had a fair amount going for it: re passenger transport anyway, it had advantages over 4 feet 8-and-a-half-inch, vis-a-vis speed, comfort, spaciousness, stability and safety. Things just worked out that the 7 ft. gauge caught on only in the south-western “chunk” of Great Britain: effectively, “4-8-and-a-half” obtained everywhere else in the country – and trans-shipment between gauges, for both freight and passenger, was a nightmare: whence ultimate complete victory for the narrower gauge.

It’s a frequent – understandable – misconception that breadth of track gauge, as opposed to loading gauge, is the big limiting factor for how much and how effectively, trains can carry. This is a thing which shows up in Bill Bryson’s book on Australia (which country was – owing to various original causes – long plagued by a mixed-up situation of several different gauges). Bryson mentions – correctly – that one gauge widely used in Australia, was 3’ 6". He goes on to describe that as “a width not far off that of amusement park rides; people must have ridden with their legs out of the windows”. I often find Bryson annoying in his – when writing non-fiction – blithe disregard of facts and prioritising of clowning-around; but, discounting his predictable grotesque and over-the-top way of putting things, I feel that here he can be forgiven for an honest misunderstanding. In fact, a good many parts of the world have their rail systems on 3’ 6" gauge; which systems, with a generous loading gauge, can accommodate positively huge locos and rolling stock.

I’m in the UK, and this rings no bells with me; admittedly, I take more interest in railway matters from times past, than in present-day doings.

Heck, it’s surprising enough that passengers don’t have their legs out the windows on 4’8.5" track. One wouldn’t think that something as wide as a train could balance on such a narrow base… but given that it can, why not a narrower one?

It wasn’t an “excursion railroad.” Toledo Jim is talking about the Nightstar rail service which was planned to be the night train version of the Eurostar. These would have been overnight sleeper trains that ran through the Chunnel, providing direct overnight travel between between Britain and parts of Europe.

FWIW, excursion is a term of art used in North America at least to refer to railroad trips organized for the benefit of rail fans, typically using restored ancient rolling stock and visiting little-used or non-revenue lines, and generally ending back where they started.

The inimitable Feynman explains the principle.

As Narrow Gauge can be as low as 20 inches, and Miniature — those usable rideable hobby railways — as low as 3", much can be done to keep people on track.
However most sensible people in Britain still mourn the defeat of Brunel’s 7 foot gauge. A most superior ride.

The Cincinnati Waterworks still has remnants of an 18" narrow gauge rail system used for hauling coal and ashes around the property. It wouldn’t really count since it wasn’t a common carrier, but even mining railroads didn’t usually use that narrow of a track gauge http://www.jjakucyk.com/transit/cgpcalifornia/large-16.html

The waterworks was also served by the Cincinnati, Georgetown & Portsmouth Railroad, which for a brief period in 1902 operated three different track gauges (3’-0", 4’-8 1/2", and 5’-2 1/2") concurrently while it was converting from a narrow gauge steam shortline railroad to a standard gauge electric interurban railway, with some broad gauge rails and cars to operate city service to downtown over the street railway. http://www.jjakucyk.com/transit/cgp.html

So has the Royal Gunpowder Mills in Essex, what is left of it.
18" wooden rails, 4.5 ton locos running on paraffin, pulling 18 ton rushing along at 6mp, they weren’t taking any chances with safety.

Yes, I guess excursion wasn’t the right word here, I was thinking of something along the lines of some travel services here (like Rocky Mountaineer) that own and operate trains, but do not own the track and fixed plant they run on. BC Rail in Canada is somewhat similar.
Amtrak and VIA each own at least some of the track they run on.