Talk:Railroad switch

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[edit] Foreign terms

Removed "the German term is Eisenbahnweiche" -- no reason for the article to include foreign-language equivalents of terms (if German, why not French etc.?) -- Picapica 12:30, 4 Dec 2004 (UTC)

It crept back in; I took it out again. It's in the interWP links.

This is inconsistant, to find out why, see this page for an example.Myrtone

[edit] Separate articles

Anyhow: IMO derailler and gauntlet should be on their own pages. Esp since not all deraillers are points, although even some of that type have "switchstands". (Otherwise y'might's well throw diamond crossing in here too, and rename it Frog (railway).) Kwantus 22:23, 2005 Jan 26 (UTC)

I agree that gauntleted track should be in a separate article. In normal circumstances there are no moving parts, so there is no "switching" involved. The same goes for diamond crossings, mentioned below. Will move gauntleted track, anyway, if no objections within the next few days. -- Picapica 8 July 2005 16:58 (UTC)

Agree with Kwantus on derails (I assume the term "derailer"/"derailler" is British; correctly or not, it is referred to as a "derail" by the railroads I'm familiar with and also in GCOR, which is the governing rulebook for almost all West Coast railroads). In fact, of the dozens of derails I've run across, all but one are of the type shown in the image Kwantus posted--only one would be even remotely like that described in this article (when in the derailing position, it basically splits the rail apart--hard to describe). I'm not sure that there's enough content to justify "derail" being its own article, but it is sufficiently different from a switch that it's worth considering. cluth 23:53, 17 September 2006 (UTC)

Also agree in making a separate article on Gantlet Track. The originator of this type of track was Prof. TSC Lowe who needed to come up with a solution for his Mount Lowe Railway funicular when his designer-engineer David Macpherson told him that the required grading for the common four-rail would be extensive and costly, mostly for the fact that there was a great chasm to backfill in order to accomplish the proper width. Overnight Lowe came up with his version of a "passing track" which allowed a three-rail funicular with the four-rail section only required at dead center. The passing track was listed as a point of interest with its own signage and all. It also became a world wide standard for funiculars. Magi Media 14:50, 16 February 2006 (UTC)Magi Media

I came here to agree with the separate-article proposal ...which I now see I proposed myself nearly 9 months ago (and then forgot about)! -- Picapica 11:29, 26 March 2006 (UTC)

Separate Gantlet track article now created. -- Picapica 12:34, 26 March 2006 (UTC)

[edit] What is a frog?

I don't really get what a frog is (both in the context of switches and on crossings and gauntlet tracks) - can someone possibly color in the frog on a picture of a switch (and the other setups)? Also, is the etymology of the term known? --SPUI (talk) 03:07, 15 Feb 2005 (UTC)

Ah, I think I understand. So the end of a gauntlet/gantlet track setup also has one frog, and a crossing of two railroads with no switches has 4? --SPUI (talk) 05:42, 15 Feb 2005 (UTC)

Correct. The frog proper is the triangular meeting of two rails at the heart of this assemblage: [1] (it's taken from a piece of electricified model railway track - hence the isolation gaps either side of the assemblage; they wouldn't be there in the prototype). The etymology, I believe, is from the fact that the appearance of this triangular bit of rail reminded the early rail engineers of the "frog" in a horse's hoof - see here: [2] (people were more into looking closely at horses' hooves in those days, you have to remember!). And the name of the horse's hoof frog itself was no doubt inspired in turn by the triangular shape of a frog's body: [3]... -- Picapica 8 July 2005 17:39 (UTC)

I dislike use of the term 'frog' in this context, a term I'd only associate with model railways. On the 'real railway', it's alway referred to as a 'crossing', in my experience.—The preceding unsigned comment was added by 81.77.170.235 (talk • contribs) 18:23, June 26, 2006 (UTC)

(in which country nd period?) —The preceding unsigned comment was added by Hugh Watkins (talk • contribs) 04:20, July 12, 2006 (UTC)

Hmm. I think that there's plenty of evidence that frogs are still alive and well on the real railway. Some examples: [4] [5] [6]. -- Picapica 15:47, 13 August 2006 (UTC)

Yeah, it probably depends on the country. Here in the U.S., they're definitely known as frogs by railroaders. And be careful about causing even further confusion: I'm not sure how the U.K. does things, but here in the U.S., a crossing is a place where a road crosses the tracks (more officially known as a "grade crossing" or an "at-grade crossing"). cluth 23:47, 17 September 2006 (UTC)

I don't think we should start to get paranoid about what we call the individual parts (and more importantly, explain to a lesser mortal what and how it works) . So long as we know what we are talking about and we include alternative names in parenthesis.--7severn7 11:14, 15 September 2006 (UTC)

I removed this:

One origin of the term "frog" gives its name to the frog war, a conflict that occurs when a railroad company attempts to cross the tracks of another. Another reason given for the use of the word "Frog" to describe this device that it is where the wheel "jumps" over the rail, like a frog jumping. In French, this device is also known as a "bifurcle"--the location where the rails bifurcate in a turnout.

as (1) the first explanation looks like circular reasoning (rail frogs were named as such long before before there were "frog wars") and (2) there is no such French word as "bifurcle" -- the French term is "cœur (de croisement)". -- Picapica 22:41, 28 February 2007 (UTC)

[edit] Diamond Crossings (Switches shaped like an X)

I think we need to include Diamond Crossing (I dont know what the technical term is.) They used quite commonly. For instance where a branch crosses over onto a relief line. I am thinking also of the crossing north of Newark in England, where the local line crosses the ECML.

Also a disambiguation page for "crossing" as opposed to "crossover"

Their are several terms for this. We like to call them Exicornts because they look like X's between tracks the run parallel. Other known terms: Scissors crossover, diamond crossover, and double crossover. I recently added the Exicornt term to this site, but their is a dispute as to whether the word exists and whether or not the page should be deleted or merged.EddieSegoura 03:35, 24 November 2005 (UTC)

A crossing (as I understand it) allows to lines at an angle to cross (as in the case mentioned above) unlike a crossover. Since there are no moving parts, I suppose it is technically not a switch, but perhaps the difference should be mentioned.

[edit] The main figure

I would suggest to replace the main (first) figure by one of the multiple pictures of the real switches. I am not sure if we need the toy switch picture here, and it actually does not look very well. Audriusa 17:07, 10 February 2006 (UTC)

Agreed. But not replace with real switchs. How about a diagram of how a switch works, animated so it shows the two postions it can be in?

Now replaced with an image of the real thing. (Animation will have to await someone more skilled, however!). -- Picapica 12:20, 26 March 2006 (UTC)

Lol I was bored, so here. Animation It sucks though, so be warned. This is just a very basic diagram of it, not fancy at all.

[edit] Frogs

Three times in the article frogs are described as castings. For strength, aren't they in fact always forgings? The expense of forgings was the reason given by British Rail when it was trying to save money by reducing double to single turnouts at junctions (thus reducing flank protection) and not having provided catch points at the site of the Cowden train crash. Moonraker88 06:54, 1 June 2006 (UTC)

They really are cast. The material of these frogs is a high Manganese austenitic steel, unforgable because of its high work hardening quality. Many other rail parts are forged. Meggar 04:05, 3 August 2006 (UTC)

Great – thanks for putting me right. Moonraker88 07:29, 3 August 2006 (UTC)

[edit] Double slip switch

Removed reference to English switch (Mainland Europe). It is really called this only in Dutch (Engelse wissel). (We don't need to say that an adjustable spanner is also known as an "English key" just because of Spanish llave inglesa, etc.) -- Picapica (PS Hope to add letters to the image of the double slip soon -- no access to suitable software at the moment)

[edit] Outside slip

As soon as I find an image of an outside slip I'll post a link.--7severn7 11:10, 15 September 2006 (UTC)

[edit] Commonwealth vs US usage

I understand that Wikipedia is a multinational project, and I've always tried to be sensitive to how countries outside of the U.S. use the English language (which, admittedly, we did not invent). I definitely don't go around editing articles to conform all to American usage. However, the radical difference in terminology between North American railroads and railways in the rest of the English-speaking world can lead to some very choppy and inconsistently-written Wikipedia articles. In most rail-related articles, it's very obvious that the articles were written by many different people, as terms, usage, and style vary wildly between paragraphs and even sentences in the same paragraph. Non-cohesive writing is, I believe, somewhat destructive to the sense of flow and order that should be in every Wikipedia article.

I'm not sure what the solution is--I hesitate to call for standardizing terminology to one standard or the other, and it's very cumbersome to put "U.S.: xxx, U.K.: yyy" (or the longer but more inclusive and accurate "North America: xxx; Commonwealth: yyy") at every point (no pun intended) in the article . Any suggestions? Or do you all vote that it's OK as is?

I'm going to place a copy of this post in Wikipedia talk:WikiProject Trains#The Regional Terminology Problem--the discussion's kind of started there. cluth 02:29, 18 September 2006 (UTC)

It appears that in Wikipedia_talk:WikiProject_Trains#Railway_station_v_Train_station, User:JYolkowski said that Wikipedia:Manual of style#National varieties of English says that it's OK to be inconsistent across articles as long as you're consistent inside each article--and that it probably works best to defer to the style used first in each article. That makes sense, but it still presents problems in places like crossing loop that were mentioned in the Regional Terminology Problem section. To keep things from getting confusing, if you have a reply on this subject that's not related to this article, please post it at Wikipedia talk:WikiProject Trains#The Regional Terminology Problem. Thanks! cluth 02:41, 18 September 2006 (UTC)

[edit] Winter operation

i did not see discussion in the article of winter operation of switches. A build up of snow and slush which freezes solid can prevent the switch from operating correctly. In rail yards, I have seen electrically heated switches and switches heated by gas flames. Along the line, in Canada or the northern United States, how are switches operated out in the country? Do they have ac power run to them with electric heat, or do the switchmen carry gas torches for melting the ice build up? I know that in the early to mid 20th century the Section Foreman's job included making the rounds all night and sweeping snow off the switches to make sure they were operable, but I can't envision that with today's reduced work force.Edison 20:28, 1 October 2006 (UTC)

[edit] Oliver Brown's edits and questions

First, let me compliment Oliver Brown on his recent work on this article. It is a big improvement. However, I have some questions. Highlighted passages are quotes from the article.

In talking about trailing through points set the wrong way, there is mention of "variable switches". What are these?
On lines with heavy and/or high-speed traffic, a movable point frog is often used. As the name implies, there is a second set of points located at the frog.
Is this ever true? The linked article talks about the V of the frog moving, not additional blades.
Two switch machines are required to make a movable point frog switch work.
How true is this? I can accept that two machines might be normal, but are two actually required? Surely with appropriate rodding the one machine could operate both blades plus the frog?
Guard rails on the outer rails are not needed with the one-piece cast frog as they are part of the casting.
I had no idea what this meant until I had a close look at one of the pictures, but is this always true?
A points lever, ground throw, or switchstand is a lever and accompanying linkages ...
Is a switchstand actually a lever, or is it a device to indicate the lie of the points? The accompanying picture appears to show the latter, although perhaps they are combined levers and point indicators? Regardless, point indicators are not (yet) covered in the article.

Philip J. Rayment 09:29, 11 December 2006 (UTC)

Thanks for the compliments, and thanks for tidying up after me! I hope to get stuck into the rest of the article at some point in the near future. As for you questions, unfortunately I only have limited knowledge of UK usage, so I don't really know. Ollie 12:59, 11 December 2006 (UTC)

[edit] Trap points and catch points

I've posted a question at Wikipedia talk:WikiProject Trains#Catch points and trap points about the difference between trap and catch points, with the hope of clearing up the differences (whether one definition is incorrect, or there is some difference in terminology) and making this article agree with the information at Catch point. If anyone feels they can help in this regard, it'd be great if you could reply at the link above! →Ollie (talk • contribs) 20:57, 17 December 2006 (UTC)

[edit] High Speed Switches

Perhaps someone could tell us if switches can be used on really fast trains - eg. TVG does 199 mph. Anyone know how slow they need to go to handle these?martianlostinspace 14:48, 3 January 2007 (UTC)

Answered my own question. The TGV article records an accident of a train going over points at 168 mph, although the point was not the cause of the derailment. I take this as assuming that the TGV is designed to pass over points at this speed. If you disagree, RV.martianlostinspace 15:03, 3 January 2007 (UTC)

I have reverted, for a couple of reasons. First, it was not a very encyclopedic statement; it was more like gathering notes to solve a puzzle. Second, it could be quite misleading if the speed that TGV trains go through points is nothing like this figure. And this appears to be the case. Doing a bit of research, I found this mention of points designed for a diverging move of 220 kph/137 mph, but there's no reason to think that's the upper limit. The same page also records a record-test train going over points at 501 kph (also mentioned here), but it is not clear that the train was doing the diverging move. Philip J. Rayment 08:52, 4 January 2007 (UTC)

[edit] How does the train stay on the track?

It is requested that a diagram or diagrams be included in this article to improve its quality.
For more information, refer to discussion on this page and/or the listing at Wikipedia:Requested images.

It's never been entirely clear to me how a train passing over a switch like this doesn't fall off the track. Or exactly how extra rails like this are helpful. Some diagrams would be very informative. It would be especially helpful to point out which elements of the wheel and rail have standardized dimensions, and which are allowed to vary. This article mentions 75-degree flanges and 1:20 tapers, and it would be helpful to explain such terms. -- Beland 17:14, 13 January 2007 (UTC)

[edit] Guard rails

Removed this: Guard rails on the outer rails are not needed with the one-piece cast frog as they are part of the casting.

One-piece cast frogs do not obviate the need for guard (check) rails on the inner side of the stock rails. It is the wing rails, not the guard rails, that are incorporated in a one-piece cast frog. -- Picapica 23:00, 28 February 2007 (UTC)

I had never seen a one-piece cast frog before seeing the picture on here, but it appears to me that with such an arrangement, the need for guard (check) rails is obviated. Guard rails work by preventing the wheels taking the wrong route through the frog by contacting the back of the flange of the opposite wheel. With the pictured frog, the wheels are prevented from taking the wrong route by the raised sections contacting the back of the wheel going through the frog. Thus the normal guard rail would not be needed. Furthermore, as the raised sections do the job of the otherwise absent guard rails, perhaps the raised sections are known as guard rails(this is just speculation)? Philip J. Rayment 01:45, 1 March 2007 (UTC)

I like that commentary, Philip: you make some good points (<-- sorry about that!). It's a pity, though, that we haven't got an image conclusively showing the absence of stock-rail guards in a switch fitted with the kind of frog pictured. Like you, I've never seen such a frog in situ, but I find it hard to believe that the usual railway belt-and-braces attitude would permit their being dispensed with. In any case, one-piece frog castings do not have per se to be of this particular design: see [7] for an image of a one-piece cast frog accompanied by the usual guard rails. I shall need to do some more investigating! -- Picapica 11:16, 1 March 2007 (UTC)

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