# How are wheels affixed to railroad cars? **URL:** \ **Category:** Factual Questions\ **Created:** [December 29, 2015, 8:24pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675 "2015-12-29T20:24:37Z")\ **Posts on this page:** 11\ **Page:** 2
**Author:** ![friedo](https://avatars.discourse-cdn.com/v4/letter/f/8edcca/32.png) [@friedo](https://boards.straightdope.com/u/friedo)\ **Post date:** [December 31, 2015, 9:33pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/21 "2015-12-31T21:33:39Z")
> [@jtur88](#): > > Can anyone explain why they can’t just build the trucks with two wheels on each end of each axle, so they can just roll from one track gauge onto the other? That would interfere with the check rails at turnouts and such. ---
**Author:** ![GaryM](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/garym/32/241_2.png) [@GaryM](https://boards.straightdope.com/u/GaryM)\ **Post date:** [December 31, 2015, 9:34pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/22 "2015-12-31T21:34:04Z")
It would make construction of switches difficult. It’s probably not impossible though. ---
**Author:** ![Sangahyando](https://avatars.discourse-cdn.com/v4/letter/s/f14d63/32.png) [@Sangahyando](https://boards.straightdope.com/u/Sangahyando)\ **Post date:** [December 31, 2015, 10:20pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/23 "2015-12-31T22:20:24Z")
> [@Sangahyando](#): > > A large part of Russia’s reason for originally choosing 1520mm gauge for the country’s railways – rather than 1435mm, standard for most of Europe (and North America) – was to make things more difficult for prospective wartime invaders. > [@SirRay](#): > > I’ve long ago heard that hinder invasions was not really a reason for the choice of Russian broad gauge, and the [wiki entry on Russian gauge agrees](https://en.wikipedia.org/wiki/5_ft_and_1520_mm_gauge_railways#Russian_Empire.2C_1842): Thanks ! Something indeed often asserted by amateurs of European railways; but, I learn here, seemingly a bit of an urban legend. Maybe a thing suggested to people, by Russia’s long-standing and widely-observed xenophobic streak? ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [December 31, 2015, 11:09pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/24 "2015-12-31T23:09:31Z")
> [@Sangahyando](#): > > Germany when advancing into Russia, just narrowed lines’ gauge to 1435mm: That’s 85 millimeters, or about 3 1/3 inches. How did the Germans do that–and how did they get away with it? ---
**Author:** ![jtur88](https://avatars.discourse-cdn.com/v4/letter/j/e9c0ed/32.png) [@jtur88](https://boards.straightdope.com/u/jtur88)\ **Post date:** [December 31, 2015, 11:15pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/25 "2015-12-31T23:15:28Z")
> [@GaryM](#): > > It would make construction of switches difficult. It’s probably not impossible though. Wouldn’t it just require a small gap in the rail near the switches, to let the extra flange through? ---
**Author:** ![Sangahyando](https://avatars.discourse-cdn.com/v4/letter/s/f14d63/32.png) [@Sangahyando](https://boards.straightdope.com/u/Sangahyando)\ **Post date:** [December 31, 2015, 11:49pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/26 "2015-12-31T23:49:02Z")
> [@dougie\_monty](#): > > That’s 85 millimeters, or about 3 1/3 inches. How did the Germans do that–and how did they get away with it? Alter things so that the two rails are 85mm closer to each other, than they were previously. Simple enough, surely – or is this a “whoosh” situation? ---
**Author:** ![dougie\_monty](https://avatars.discourse-cdn.com/v4/letter/d/439d5e/32.png) [@dougie\_monty](https://boards.straightdope.com/u/dougie_monty)\ **Post date:** [January 1, 2016, 12:43am UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/27 "2016-01-01T00:43:22Z")
> [@Sangahyando](#): > > Alter things so that the two rails are 85mm closer to each other, than they were previously. Simple enough, surely – or is this a “whoosh” situation? So they smack the rails together with sledgehammers or something? ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [January 1, 2016, 3:29am UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/28 "2016-01-01T03:29:12Z")
> [@dougie\_monty](#): > > So they smack the rails together with sledgehammers or something? Well yes, but of course you remove pins , move the track, install the pins… the pins come out and go back in with the use of the sledgehammer, so in loose terms, you are right, thats the basic skill required…" Can your people use sledgehammers ? Yes ? Good, so go move the track then…" But perhaps an incomplete description, to the point of misleading… that was intentional trolling wasn’t it … ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [January 1, 2016, 12:43pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/29 "2016-01-01T12:43:39Z")
The earliest railways in Britain has several different gauges too. Mines tended to go for a narrow track as the trucks were smaller anyway. Heavier locomotives needed stronger rails and by the time George Stephenson built the Stockton and Darlington line, he was using the same gauge as the earlier Killingworth line, 4 ft 8 in. When Brunel built the Great Western Railway, he decided on a wider gauge, to give greater stability, and adopted a gauge of 7 ft. The extra ½" was added to both lines to allow more flexibility. They were big rivals and as the network spread, each new line tended to choose one or the other. Of course the Victorians were busy selling British expertise overseas and this tended to spread the 4’8½" gauge, although British South Africa had 3’6" gauge. Mixed gauge tracks still exist around the world but they make for complexities and higher maintenance costs. > **[Track gauge](https://en.wikipedia.org/wiki/Track_gauge)** > > In rail transport, track gauge (in American English, alternatively track gage) is the distance between the two rails of a railway track. All vehicles on a rail network must have wheelsets that are compatible with the track gauge. Since many different track gauges exist worldwide, gauge differences often present a barrier to wider operation on railway networks. > The term derives from the metal bar, or gauge, that is used to ensure the distance between the rails is correct. > Railways also deploy ... ---
**Author:** ![LSLGuy](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lslguy/32/5813_2.png) [@LSLGuy](https://boards.straightdope.com/u/LSLGuy)\ **Post date:** [January 1, 2016, 1:21pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/30 "2016-01-01T13:21:36Z")
It’s far, far cheaper & easier to modify your trains to run on different gauges than it is to pull up and re-lay 100% of the tracks and switches. You can even stockpile large supplies of other-gauge trucks in advance of the war. Better yet to capture some enemy trains and use them on their own tracks. You just transfer cargo from your trains to theirs at the pre-war borders. And as noted in the wiki on Russian Gauge (see post #14 & #19), rail networks are prime targets for aerial destruction and for retreating armies to destroy as well. Military truck convoys can deal with cratered roads pretty well. Military trains are stopped cold by a 3 foot damaged section of track. To be sure both kinds of damage can be repaired. Eventually. With enough supplies, manpower, and time. ---
**Author:** ![Sangahyando](https://avatars.discourse-cdn.com/v4/letter/s/f14d63/32.png) [@Sangahyando](https://boards.straightdope.com/u/Sangahyando)\ **Post date:** [January 1, 2016, 3:26pm UTC](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675/31 "2016-01-01T15:26:08Z")
> [@bob\_2](#): > > Of course the Victorians were busy selling British expertise overseas and this tended to spread the 4’8½" gauge, although British South Africa had 3’6" gauge. Mixed gauge tracks still exist around the world but they make for complexities and higher maintenance costs. > > [Track gauge - Wikipedia](https://en.wikipedia.org/wiki/Track_gauge) Tendency was, for four-feet-eight-and-a-half-in. (1435mm) to become the scene in more-developed parts of the world (those which didn’t opt for a different “wide gauge”); whereas as from about two-thirds of the way through the 19th century, somewhat narrower gauges (such as 3’6", as above) were widely used for new railways in relatively more rugged, less-developed, areas of the globe. As touched on in the linked Wiki item, a narrower gauge allowed for lower construction costs; and tighter curves, making it easier to cope with rough and hilly terrain. A potential “downside” was, of course, problems with transfers in whatever way, between narrower and wider gauges. Oddly enough, the first nation to inaugurate true railways on the 3’6" (1067mm) gauge was, of all places, Norway – rugged and mountainous country, sparse population. After considerable governmental deliberation, this gauge was decided on for most of Norway’s earlier-built lines (re the “Imperial” measurement, some influence suspected from British engineers whose advice was sought in the debates). 3’6" gauge was thereafter used in much of the British Empire (South Africa as above, and elsewhere) – also Japan. The quite similar width-wise, gauges of 1 metre; and three feet (917mm); also saw widespread use on lines opened in relatively remote, difficult-terrained areas of the planet. [Previous page](https://boards.straightdope.com/t/how-are-wheels-affixed-to-railroad-cars/741675.md?page=1)