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Need advice on trackplan - interlocking towers

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Posted by exPalaceDog on Saturday, December 2, 2006 5:46 PM

 

Now that the Old Dog has completed his battle with one of Microsoft Word's less useful features, automatic paragraph spacing, let's get started.

 

 Dave-the-Train wrote:

Clearly we are falling over the issue of era and, sometimes individual RR's practices.  We aren't going to solve this on a "generic" / "run what ya brung" layout.  Mtrails is stuck with finding compromises.  This is one reason I don't get much involved with club layouts.

 

There is an old saying, "A camel is a horse designed by a committee."

 

 Dave-the-Train wrote:

As far as the laddr goes the main thing to watch out for is that too many changes of direction increases the likleihood of derailments/jack-knifing.

 

That design for a yard would be used strictly for car storage on a "real" RR for just that reason. It is an attempt to get as many cars as possible in a limited area. Such a yard would normal be in an area where land costs are low. It might for something like storing cars when a Midwestern RR is getting ready for the grain rush.

 

 Dave-the-Train wrote:

Absolute Block in the UK is different from ABS in the USA... which is why I wrote it out in full.  It remains that a colour light signal head of a particular kind (in itself) can be doing one of several jobs (one at a time and one at each location - this is why engineers need route knowledge... have you ever thought about those signals having numbers plates etc?  they're not very big are they?  So a Driver has to stop to read them or know them from experience if he is rolling by).

 

First, note that there is fail safe feature, if the plate falls off, the signal must be treated as an absolute signal. The driver does not need to read the plate, he only needs to see that it is there. "Route knowledge" can be a "bad" thing. One driver I know got an unpaid vacation because the RR changed the speed limit on a section of track and he failed to notice the new sign and/or read the bulletin board.

 

Second, sins of omission are harder to detect than sins of commission. Where "route knowledge is important is when the driver fails to see a signal where he know one should be there. A dead signal, say burnt on lamp, is supposed to be treated as if it is displaying it's most restrictive aspect.

 

 Dave-the-Train wrote:

Semahore arms in the US point the other way 'cos most of you drive on the wrong side - except the CNW for one... can't say that I've noticed where there semaphores are though Blush [:I]as I model diesel era.

 

 

We drive on "right" of the road, it is you all the drive on the incorrect side. ;-)

 

 

 Dave-the-Train wrote:

Train Order Signals (as you probably know) are usually just outside the office and back-to-back on the same post - so that on approach one arm sticking out to the right will show its face and the other, sticking out to the left, will show its back.  Green/Board straight up meant clear to run through/no orders.  Yellow/45degrees meant clear to run through BUT picking up Orders on the move (both loco and conductor).  Red(???) /horizontal meant Stop and sign for Orders.

 

True, if the signal can display three aspects. But what if one is using two aspect signals such a lower quadrant semaphore? Two arms per direction?

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

 

The Old Dog has this matter some additional though;

 

 exPalaceDog wrote:

The word "Absolute" in ABS confuses the Old Dog. Home signals at an interlocking are always "absolute", the train stops and remains stopped until the signal clears. With "block" signals, it would seem to the Old Dog that two types are necessary. Take section of line, say ABCD with passing/meeting sidings at A and D. Clearly, the eastbound signal at A must be an absolute signal if there is a West bound train between A and D. Also, the West bound signal at D must be absolute if there is an East bound train between A and D. But otherwise, they can be "permissive" "stop" signals (stop and then proceed at restricted speed (10 mph)).  The signal at BC would probably always "permissive" sense the can not prevent conflicting movements.

 

First, the rule book referred to the squared end semaphore as an absolute stop. An interlocking home signal would be such a signal. But that does mean that such signal could NOT be used elsewhere for other purposes.

 

Second, it is mainly the dispatchers to keep trains moving in opposite directions from trying to occupy the same track between the same to sidings. The main function of block signals is to keep a following train out of the leading train's caboose.

 

Third, the situation about is something of a non-problem. If a east bound train is to follow another east bound train, the second train will only be held up until the first train passes signal B.

 

Have fun

 

 

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Posted by Dave-the-Train on Saturday, December 2, 2006 6:26 AM

Clearly we are falling over the issue of era and, sometimes individual RR's practices.  We aren't going to solve this on a "generic" / "run what ya brung" layout.  Mtrails is stuck with finding compromises.  This is one reason I don't get much involved with club layouts.

As far as the laddr goes the main thing to watch out for is that too many changes of direction increases the likleihood of derailments/jack-knifing.

Absolute Block in the UK is different from ABS in the USA... which is why I wrote it out in full.  It remains that a colour light signal head of a particular kind (in itself) can be doing one of several jobs (one at a time and one at each location - this is why engineers need route knowledge... have you ever thought about those signals having numbers plates etc?  they're not very big are they?  So a Driver has to stop to read them or know them from experience if he is rolling by).

Semahore arms in the US point the other way 'cos most of you drive on the wrong side - except the CNW for one... can't say that I've noticed where there semaphores are though Blush [:I] as I model diesel era.

Train Order Signals (as you probably know) are usually just outside the office and back-to-back on the same post - so that on approach one arm sticking out to the right will show its face and the other, sticking out to the left, will show its back.  Green/Board straight up meant clear to run through/no orders.  Yellow/45degrees meant clear to run through BUT picking up Orders on the move (both loco and conductor).  Red(???) /horizontal meant Stop and sign for Orders.

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Posted by exPalaceDog on Friday, December 1, 2006 3:46 PM

 mtrails wrote:

The compound ladder I got out of a book of HO trackplans (borrowed the book, don't remember the title). I figured, heck, I can use the same number of turnouts, and be able to store up to three more cars in the same space. Okay, so you might say "hmmf, so what's three cars, when a simple ladder could make operation easier?" Again, I'm talking about a club, and everyone want's their cars on the layout.

 

 

If you want to get the most cars in the yard, you might want to think about a switch back yard.

 

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Have fun

 

 

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Posted by exPalaceDog on Friday, December 1, 2006 3:17 PM

 Dave-the-Train wrote:

I'm not sure but I suspect that you are overlapping two or more different train operating systems.  Train Orders are basically a seperate system from CTC and Absolute systems controlling movements by signal indication.  As far as I am aware the systems do not overlep but I am open to correction on this.

 

With CTC the signals basically communicate the "train orders" to the crew by signal aspect. It is a much newer process then the items the Old Dog is talking about.

 

 Dave-the-Train wrote:

 

Also, as I understand it, Train Orders were given to trains at Train Order Stations/ Offices which did not necessarily have to be towers.  Further towers were not necessarily Train Order stations/offices. 

 

 

 

True, in fact most "train order offices" were located at stations since stations are much more common then "towers".  In some rare cases, in remote areas, there might be an "office" without a "tower" or "station" being present.

 

Almost all manned "towers" would be "TO offices", since they would need to coordinate with other RR installations by telegraph. If one has a telegraph operator present, he might as well handle TO's as needed. In fact, in a "tower" where two separate RR's crossed at grade, the "tower" would often be a "TO office" for both roads.

 

 Dave-the-Train wrote:

 

This is similar to the fact that not all Signalboxes in the UK are Block Posts. 

 

 

 

Same over here, in with an automatic (track circuits) blocking system the "block" signals would rarely be at stations or towers. The Old Dog was referring the manual (hand operated) block signals.

 

But clearly the interlocking towers would need to be tied into the block signals in some cases. Take a section of line, ABC with a crossover at B. It would make no sense to allow an west bound train to cross over at B to the south track if there was a east bound train on that track between A and B.

 

 

 Dave-the-Train wrote:

The simplest examples in both countries are grade crossing towers/boxes... they may only look after the road crossing and do nothing to regulate trains except to control their movements over the crossing.  

 

Same over here, in modern times crossing gates would usually be operated by a track circuit. In older periods they were usually operated by gate guards (not to be confused with the UK usage of "guard" which means train conductor). 

 

 Dave-the-Train wrote:

 

[Whether a box/tower has responsibility for a grade crossing is a different issue.  In the UK at least (and I'm pretty sure in the US as well) grade crossings do not exist as far as the operating system goes. 

 

 

 

True, the Old Dog was merely suggesting that if a highway crossing existed near enough to a tower, the RR might choose to have it operated from the "tower" to save the expense of hiring a "guard".

 

 Dave-the-Train wrote:

 

The regulating system keeps trains apart, routes them and brings them together under controlled conditions... this can be done within a specific system such as an Absolute Block System. 

 

 

 

The word "Absolute" in ABS confuses the Old Dog. Home signals at an interlocking are always "absolute", the train stops and remains stopped until the signal clears. With "block" signals, it would seem to the Old Dog that two types are necessary. Take section of line, say ABCD with passing/meeting sidings at A and D. Clearly, the eastbound signal at A must be an absolute signal if there is a West bound train between A and D. Also, the West bound signal at D must be absolute if there is an East bound train between A and D. But otherwise, they can be "permissive" "stop" signals (stop and then proceed at restricted speed (10 mph)).  The signal at BC would probably always "permissive" sense the can not prevent conflicting movements.

 

 Dave-the-Train wrote:

What my last post was suggesting is that the tracks be divided up with one tower controlling all the movements on the main tracks (the two south tracks at the bottom of the diagram) and only the third track on each side of the wye board and a bit further away.  This would leave the wye board (and adjacent boards) tracks - except the two main tracks at the bottom) in the control of a tower at the wye.  Either directly or under the instruction of a Dispatcher the main tracks tower and wye tower would have to hand off and receive traffic between each other.

 

Requiring the tower operators to coordinate their efforts might be a dose of real life, maybe too much of a dose. With the limited range of mechanical interlocking towers, such situations were normal in the early days.

 

 Dave-the-Train wrote:

 (As a simple example a two aspect colour light signal will look eaxactly the same externally whether it is being used in an area operated under Absolute Block, Track Circuit Block, Intermediate Block, Permisive Block, Staff and Ticket or Electric token Block - (All UK operating systems but with either quivalents or similar systems in the US).  An Engineer knows which is which as part of his route knowledge.

 

I may be missing your point, or things may differ over here. Take semaphore signals; A "permissive

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Posted by Dave-the-Train on Thursday, November 30, 2006 8:29 PM

Old Dog

I'm not sure but I suspect that you are overlapping two or more different train operating systems.  Train Orders are basically a seperate system from CTC and Absolute systems controlling movements by signal indication.  As far as I am aware the systems do not overlep but I am open to correction on this.

Also, as I understand it, Train Orders were given to trains at Train Order Stations/ Offices which did not necessarily have to be towers.  Further towers were not necessarily Train Order stations/offices.  This is similar to the fact that not all Signalboxes in the UK are Block Posts.  The simplest examples in both countries are grade crossing towers/boxes... they may only look after the road crossing and do nothing to regulate trains except to control their movements over the crossing.  They will be in the "information loop" (yeuk!  I hate that jargon)! but they will not be working the regulating system.  -- Incidentally; this is not a response to your point 2 above. 

[Whether a box/tower has responsibility for a grade crossing is a different issue.  In the UK at least (and I'm pretty sure in the US as well) grade crossings do not exist as far as the operating system goes.  The regulating system keeps trains apart, routes them and brings them together under controlled conditions... this can be done within a specific system such as an Absolute Block System.  Keeping traisn from hitting things on grade crossings that are controlled is a completely different issue.  A controlled crossing (whatever gates'barriers there are or are not) is purely a signalling issue... when the crossing is protected (sometimes by gates/barriers) the signals may be cleared.  These will control the movement of trains but not have a regulating function within the operating system.  Got that?  Good... just to confuse you signals will sometimes both control and regulate... as in where a tower/box is both looking after the crossing and regulating traffic as a Block Box/Tower.

What my last post was suggesting is that the tracks be divided up with one tower controlling all the movements on the main tracks (the two south tracks at the bottom of the diagram) and only the third track on each side of the wye board and a bit further away.  This would leave the wye board (and adjacent boards) tracks - except the two main tracks at the bottom) in the control of a tower at the wye.  Either directly or under the instruction of a Dispatcher the main tracks tower and wye tower would have to hand off and receive traffic between each other.

This is distinct from organising the practical 12"=1' world of MRR operators - your point is sound on that - If they start to seperate out the ops as I've suggested though it will help in making the decisions related to that MRR issue.  The way I've looked at it is to ask how the real RR would divide things up for practical operation.  Most MRR people don't have experience of this or means of understanding how things are divided up on the ground on the real RR... and "interpretation" ca be coloured by MRR experience and myth- some of the things I've seen as explanations of UK practice are mind boggling.

Okay... operating systems work with/using/through signal systems... but the two are not the same thing.  Signals are one measn of communication.  They are used to convey instructions according to the Rule Book and do so in the context of the operating system in force at the location.  (As a simple example a two aspect colour light signal will look eaxactly the same externally whether it is being used in an area operated under Absolute Block, Track Circuit Block, Intermediate Block, Permisive Block, Staff and Ticket or Electric token Block - (All UK operating systems but with either quivalents or similar systems in the US).  An Engineer knows which is which as part of his route knowledge.

A through track in a yard does not have o be a main track... it can just be a track that is left clear so that trains may work through the yard between main tracks or between main track and another facility, or between facilities.

In this context a through track wouldn't be a bad track to connect a caboose track (or a loco "ready track" to as it would normally be clear so that cabooses or locos could be scooted in or out of their tracks without any worry about what else was going on in the yard... and a yard track wouldn't be lost to keep access open.

Please don't take this as criticism...'cos that isn't what it is.  Hopefully it will help you understand what is going on in a broader context.

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Posted by exPalaceDog on Thursday, November 30, 2006 6:40 PM
 mtrails wrote:

The through track lableing is a consideration of future expansion. Of course this would make it the mainline. I may have labeled the wrong track? I have been studying as many existing HO trackplans in MR, and see a lot of them with yards, that do foul the mainline, both through and stub. In our case, being space limited, the plan tries to accomodate as many yard functions as possible, though they may not be played out by the book.

The question depends on what is being modeled. If you are modeling a short line, a branch line, or a secondary mainline that does not see that much traffic, fouling the main is no big problem. But on a heavy usage double track mainline, it can attrack unwanted management attention in a hurry. It is a question of how you view your RR.

From your description of the club, it sounds like many of the members enjoy putting a train on the main, and letting it run and are not too much into operation. Making the yard/s a seperate "playpen" would allow them to enjoy the layout while you enjoy doing some switching with interfering with them.

Have fun

 

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Posted by exPalaceDog on Thursday, November 30, 2006 6:18 PM
 Dave-the-Train wrote:

As far as conflicting ops go... use a Dispatcher / put the mains on one "through" Tower not located here and all the wye tracks on a local tower / CTC Board.  Then you only have to "talk to each other" when you want to move from the main tracks to the wye/yards and vice versa.

True, but what the Old Dog was referring to above was the people operating the layout, NOT the tower operator/s.  What I was trying to sayb was something like this; "When you position the operating controls for the layout, and the points of interest on the layout, try to do it in a manner where the club members will not want to want to be in the same space in the aisle at the same time."

 Dave-the-Train wrote:

Being on one tower doesn't mean that you can't have several things going on at once... the tower operator keeps them apart.

1) The tower operator would almost certainly be involved in the delivery of train orders to the passing trains. Note that there are two types of train order, some orders can be passed up on the fly using ahoop, other orders must be signed for requiring the train to stop. This would requirwe additional signals. The Old Dog is unsure of the relationship of such signals to the other signals in the interlocking.

2) The tower operator might be requried to control the operation of highway crossing gates near the tower.

3) In this situation this probably would not apply, buy at a junction, the operator might be required to function as a block operator on the branch if manual blocking was used on the branch.

 Dave-the-Train wrote:

You moght like to think about only putting switches in the wye and where routes would conflict on the tower and keeping all the ladder tracks on ground throws.  Less work for the towerman Big Smile [:D].  Within each yard and its lead track a switching crew can trundle around so long as they stay clear of any fouling points and/or conflicting routes (mainly the diamonds).

Absolutely! Trying to switch the yard/s with the tower controling the switches would be a communication nightmare. And one has to question if management would invest the funds for providing remote control and interlocking on the ladder tracks in a freight yard.

Have fun

 

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Posted by Dave-the-Train on Thursday, November 30, 2006 3:36 PM

As far as conflicting ops go... use a Dispatcher / put the mains on one "through" Tower not located here and all the wye tracks on a local tower / CTC Board.  Then you only have to "talk to each other" when you want to move from the main tracks to the wye/yards and vice versa.

Being on one tower doesn't mean that you can't have several things going on at once... the tower operator keeps them apart.

You moght like to think about only putting switches in the wye and where routes would conflict on the tower and keeping all the ladder tracks on ground throws.  Less work for the towerman Big Smile [:D].  Within each yard and its lead track a switching crew can trundle around so long as they stay clear of any fouling points and/or conflicting routes (mainly the diamonds).

With the through track you need to beware modelling a model.  I realise that with much of the information we get coming from MRR mags this can be difficult.  The thing to try to do is to look for phrases like "I did this to fit it in".  The trouble is that books come in generations and where, years ago, people knew from "everyday experience" that a modeller was "cheating" to fit things in the generations have succesively lost the everyday experience and the books have carried over the ideas from MRR books without a comparison to the real thing or the same background knowledge to be able to see what is going on.  I guess that the short version of this is to say that from slight variation we graduallly move to myth... if we're not careful.

Anyway... why shouldn't we just enjoy watching the trains trundle by!

[BOY! Someone has changed the setup in this system!  Looks good so far]!

I'll try to resend nmy last 3 emails.

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Posted by exPalaceDog on Thursday, November 30, 2006 10:13 AM

A couple of quick thoughts;

1) As you are probably aware, wyes (and reversing loops) require special wiring. That could get interesting!

2) Be sure you consider where the operators will need to stand when running the yards. You have the two yards (say the left yard and the right yards off the wye, plus the intermodal yard.  If the two yards off the wye are to have seperate operators with their controls on the left side of the layout, you have a conflict since both operators will want to stand where they have the best view of threir resective ladders. If the right yard is controled from right side of the layout, there may be a conflict with the operator of the intermodal yard.

Have fun

 

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Posted by mtrails on Wednesday, November 29, 2006 6:46 PM

Dave, no I didn't recieve an e-mail from you regarding turntables. Thanks for reiteration to Dog about the club's democracy. Smile [:)] Come to think of it, I didn't get notification e-mails that the above posts had been made. Hmmm...

You know, things would be so much easier if the club was set in one era, or time period! When the club ran on analog, there were FOUR main tracks! Immagine how dumb that must have looked. But obviously, to have enough track for everyone to "play" on. I have wondered why these guys simply like running trains. We have one young memeber (17) that I can understand just wanting to play, but the older guys? But i'm guilty too. According the schedule, the club has (I think) TWO prototypical operating sessions per Year. I'd like to see it at least once a month.

Regarding towers, if the idea for the intermodal yard hadn't come about, the wye-to-yard modules would have been catered to the steam/transition era. We have always wanted an intermodal yard, and never had a place for one, until this unique polygon module was made. But as Dog had suggested, perhaps a steam/transition era module could be inter-changed for scheduled operating sessions, and/or public viewing. Great idea Dog! Maybe in the future as we add on to the end of the current yard module, the intermodal yard could be relocated in a more realistic setting.

You are mixing apples and oranges. A yard is NOT just an yard! It is designed for a specific purpose. An interchange "yard" or track is simply a place where one railroad leaves cars to be picked up by another railroad. and the second railroad leaves cars to be picked up by the first railroad. It might be one track, pull the inbound cars and shove the outbound cars on to the track. It might be two tracks, one for inbound cars and one for outbound. An addition track might be provided for a run around. One end would be connected to track of the first railroad with a turnout locked with their switch lock (pad lock), the other end to track of the second railroad with a switch locked with the other road's switch lock.

Refering back to the stipulations of the clubs needs and wants, this yard is percieved, and operated differently by it's user. As I had stated several threads ago about the commodities line, being located right next to the E/W mainlines, it is viewed as a road, not actualy next to the mainline, but it's own set of tracks, going somewhere else. This rule (grrrr) is also now applied to the stub yard, as any sets of tracks that can be used for an inter-change point if one wants to model that scenario, can be used in that way. It is confusing I know, but when i'm using the yard, I might use it for classifying. Someone else might use the yard (or a selection of tracks) as an inter-change point. I also think I said it wrong, when I said "used as another inter-change point". I basicaly meant to say, a place for added operation, and movements.

If you intend the track labeled "through" to be a mainline track between two classification yards, you have a major problem. You need to provide a switching lead for the yard on the right side on the drawing. The whole idea of a lead is to allow the yard to be switched without fouling the main line. Also, you need to consider how you are going to remove the old engines from arriving trains and new engines. to departing trains.

The through track lableing is a consideration of future expansion. Of course this would make it the mainline. I may have labeled the wrong track? I have been studying as many existing HO trackplans in MR, and see a lot of them with yards, that do foul the mainline, both through and stub. In our case, being space limited, the plan tries to accomodate as many yard functions as possible, though they may not be played out by the book.

I agree with your suggestion about the caboose track coming off of the through track. Thanks!

By the way, we do have a railroad scrapyard. I forgot about it until you mentioned it!

 Jeremy

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Posted by exPalaceDog on Wednesday, November 29, 2006 5:11 PM
 Dave-the-Train wrote:

For your purposes I would look at cheating.

You need to step back if you want to allow for different eras.  (As I see it this is a bit difficult if you have an intermodal yard sitting there... it's never going to look right with steam locos... but that's democracy for you Confused [%-)]).

Three possible cheats

1) Use interchangable modulars as mentioned above for different eras. When you want to run steam, replace the intermodal yard with a freight house and team tracks.

2) Model a railroad museum (from MR suggestion years ago.

3) Model a railroad scrap yard.

Have fun

 

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Posted by Dave-the-Train on Wednesday, November 29, 2006 4:06 PM

Old Dog

I suspect that you are asking mtrails to include too much of reality in a "democratic" club modell RR envionment.  He'd probably go with some of our ideas if he could but he's tied up with what different, sometimes diverging, people want.  This is only "representative" of the real thing in the broad sense... it is far more MRR functional.

Your ideas are good though... where someone has more opprotunity to apply them.

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Posted by exPalaceDog on Wednesday, November 29, 2006 3:54 PM
 mtrails wrote:

The layout has a main, through yard which has been the main interaction of trains around the layout ( with the exception of a coal mine, a passenger depot, and the recent development of an oil refinery). There is about 178 feet of mainline (36 of which passes the main yard), and only three places to exchange with. I introduced this new yard for another interchange point, and the wye is a result of the lack of lateral space. This also presents opportunity for departing and arriving trains, as well as a challenge of operation, especially since an intermodal yard has been brought about.

 mtrails wrote:

With the provision of adding on, and a main passing through the yard, crew changes are feasable. The same with picking up and dropping off. Of course, not being a through yard, it will take several minutes longer to arrange, but the advantage in this case, might be the storage tracks on the opposite side of the mainline. Furthermore, with the destination of another yard on the layout, a point to point operation can now be achieved, as well as staging. The design of the main yard is quite versatile over the stub yard, so a manifested train out of the stub yard, could then be sorted and redirected out of the main yard. This makes the stub yard more of a destination or manifest (with the option of exchange and sorting)

 

You are mixing apples and oranges. A yard is NOT just an yard! It is designed for a specific purpose. An interchange "yard" or track is simply a place where one railroad leaves cars to be picked up by another railroad. and the second railroad leaves cars to be picked up by the first railroad. It might be one track, pull the inbound cars and shove the outbound cars on to the track. It might be two tracks, one for inbound cars and one for outbound. An addition track might be provided for a run around. One end would be connected to track of the first railroad with a turnout locked with their switch lock (pad lock), the other end to track of the second railroad with a switch locked with the other road's switch lock.

Since interlocking towers are often used where two seperate railroads cross at grade, one may often find an interchange yard at such locations.

Also note, that at times railroads may do transferr runs where a cut of cars is moved from the classification yard of one road to the classification yard of the second. Of course, the roads must connect and allow trackage rights to each other..

If you want an interchange yard, the Old Dog would suggest that you consider a car float landing. That requires additional switching since one must keep the loads on the two sides some what in balance.

Another thought, make the intermodal yard a ship/rail facility. Then make the area where you have the yard a freight pier. Put two tracks down the middle in the warehouse, then one along each edge of the pier. That could provide a very interesting structure especially if you put it on piles.

If you intend the track labeled "through" to be a mainline track between two classification yards, you have a major problem. You need to provide a switching lead for the yard on the right side on the drawing. The whole idea of a lead is to allow the yard to be switched without fouling the main line. Also, you need to consider how you are going to remove the old engines from arriving trains and new engines. to departing trains.

Also, if the "through" track is to be a main track, you will need an arrival/departure track, and run around track for each yard.

 mtrails wrote:

The compound ladder I got out of a book of HO trackplans (borrowed the book, don't remember the title). I figured, heck, I can use the same number of turnouts, and be able to store up to three more cars in the same space.

 

Again, it is a matter of how you view the "through track". If it is a main track, the hump should stay to avoid an addition turnout in the main. But you may want to add some straight track before the switch for the caboose track to avoid a "S" turn problem and the resulting derailments.Otherwise, the Old Dog would suggest putting the turnout for the caboose track in the "through" track.

Have fun

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Posted by Dave-the-Train on Wednesday, November 29, 2006 12:35 PM

You mention choosing a tower and tower location as being indicative of era in one of your recent posts.

Towers are expensive... to put it mildly.  So two things happen... when money is available or the regulating authority steps in an old tower ceases to be modified to take on new developments and gets replaced with something more up-to-date.

For your purposes I would look at cheating.

You need to step back if you want to allow for different eras.  (As I see it this is a bit difficult if you have an intermodal yard sitting there... it's never going to look right with steam locos... but that's democracy for you Confused [%-)]).

What I would suggest you do is work out a basic timeline and the shape the layout would have been at key dates.

If you go back far enough you can broadly figure out what would have needed to be the track signalling sections and the towers (using Armstrong frames) in something like the 1950s.

Some towers may have been lost over the next 2 - 3 decades and the signalling  for the surviving companies and tracks concentrated on a CTC board in one, maybe two, towers.  Then, if you're lucky, things expand, the intermodal yard gets planned... and you end up with a shiney new tower.  As I've said somewhere recently, you can have the old tower still there in alternate use or being removed to another site for preservation.

I hope this helps.

(PS did you get my e mails about the turntable? Cool [8D])

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Posted by mtrails on Wednesday, November 29, 2006 2:20 AM

First of all, thanks again Dog for the information. I have so much printed out to refer to! An interlocking tower is a part of the layout that helps set the scene for those who run in that era. With the potential expansion of the layout, it's beneficial to know where one should reside, and exactly how it operates. The inter-locking tower placement, and operation was inquired about, specifically for the wye, and yard lead(s) configuration, to accomodate the era that it would exist in. The intermodal lead, crossing the wye might represent a road accomodated by the tower, though not prototypicaly controlled, as a result of the era exchange. I can't thank you enough for your contributions.Thumbs Up [tup]

As a two-year member, to a 20 year-old club, I have stood up to point the club in the direction of realistic model railroading, vs. "playing with trains" as has been, the casual openess of it's (the club's) product. I must heavily consider the aspect in planning, that some don't care about how it works, as long at it "works", and those that do, as well as individuals whom might be intrigued. This sets the table for an conflict conference, as everyone wants things a certain way. With that, my intervention in planning, accomodating, and explanation, results in a happy club. I cannot shut down each member's suggestions, and it's tough to weigh the variables, with the outlook of future membership of those who may not join because it's not realistic enough. Obviously, the club exists on membership dues alone.

Second, it is hard to say much about the above desigh without knowing more about the layout it is part of. The single ended classification yard on a wye might make good sense on a model RR. A train could be made of, enter a mainline oval, and make several loops before returning. Each station on the line could represent several different stations depending on which loop the was on. This might make the mainline run appear longer, but would be limited to low traffic densities. Otherwise, things would get confusing fast

The layout has a main, through yard which has been the main interaction of trains around the layout ( with the exception of a coal mine, a passenger depot, and the recent development of an oil refinery). There is about 178 feet of mainline (36 of which passes the main yard), and only three places to exchange with. I introduced this new yard for another interchange point, and the wye is a result of the lack of lateral space. This also presents opportunity for departing and arriving trains, as well as a challenge of operation, especially since an intermodal yard has been brought about.

At most, three members run the layout simultaneously, and with not much to interact with, it's easy to see why dust settles on the tracks so frequently.

The compound ladder I got out of a book of HO trackplans (borrowed the book, don't remember the title). I figured, heck, I can use the same number of turnouts, and be able to store up to three more cars in the same space. Okay, so you might say "hmmf, so what's three cars, when a simple ladder could make operation easier?" Again, I'm talking about a club, and everyone want's their cars on the layout.

But on a real RR, such a yard might create some problems. For trains that are totally broken up and re-classifed, it would work. But would about freight trains that opnly change crews at this location? And what about freight trains that just drop and/or pick a cut of cars on the end?  Are such trains going to need to back in or back out of the yard? Or are such trains to be handled else where?

With the provision of adding on, and a main passing through the yard, crew changes are feasable. The same with picking up and dropping off. Of course, not being a through yard, it will take several minutes longer to arrange, but the advantage in this case, might be the storage tracks on the opposite side of the mainline. Furthermore, with the destination of another yard on the layout, a point to point operation can now be achieved, as well as staging. The design of the main yard is quite versatile over the stub yard, so a manifested train out of the stub yard, could then be sorted and redirected out of the main yard. This makes the stub yard more of a destination or manifest (with the option of exchange and sorting)

a real RR might run the rods for the inside turnouts under the outside ladder so the sitchmen would not need to cross the tracks to operate the inside turnouts.

I didn't think about the operation of the switchmen, since it's a model railroad, but I understand this circumstance around track planning, in a real sense. This point I must dismiss for reasons previously stated.

 

Jeremy

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Posted by exPalaceDog on Tuesday, November 28, 2006 6:52 PM

First, the Old Dog has found a couple additional pages on mechanical interlocking

http://www.nymr.demon.co.uk/signals/signalling_1.htm

http://modratec.com/

The above company apparently can provide software to design mechanical interlocking plants and marerials to actually build the interlocking frames.

Second, it is hard to say much about the above desigh without knowing more about the layout it is part of. The single ended classification yard on a wye might make good sense on a model RR. A train could be made of, enter a mainline oval, and make several loops before returning. Each station on the line could represent several different stations depending on which loop the was on. This might make the mainline run appear longer, but would be limited to low traffic densities. Otherwise, things would get confusing fast.

But on a real RR, such a yard might create some problems. For trains that are totally broken up and re-classifed, it would work. But would about freight trains that opnly change crews at this location? And what about freight trains that just drop and/or pick a cut of cars on the end?  Are such trains going to need to back in or back out of the yard? Or are such trains to be handled else where?

Third, if a compound ladder is desired, the Old Dog would suggest using the deesign in Custom Line Layouts - HO Scale Railroads from Atlas. Their design would eliminate that gosh awfuil ugle hunp. Although the Old Dog can't not state it for sure, it would suspect that a real RR might run the rods for the inside turnouts under the outside ladder so the sitchmen would not need to cross the tracks to operate the inside turnouts.

Have fun

 

 

 

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Posted by mtrails on Tuesday, November 28, 2006 6:38 PM

GR,

As the intermodal module is not shown in the sketch, the lower branch of the wye pictured, sets the tracks 7" from the edge of the module (where the ship will be located), and is a pretty straight approach. As drawn, the tracks crossing at a 90 degree angle over the wye is a budget conscious plan. We had the 90 deg crossing, so we might as well use it.

A few minor adjustments have been made to the latest sketch, and we are beginning to lay track. Though some of the plan is not agreeable by suggestors of this forum, and incorrect, relating to real life railroading, please remember it's still a model. It doesn't have to be perfect, nor follow prototypical guidelines, it just has to function, and from a club standpoint; for a number of lamens.

 

Thanks once again everyone for your informative suggestions. Without your help, this plan would have missed a lot of opportunitistic operation.Smile [:)]

Jeremy

YVMRC

 

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Posted by GraniteRailroader on Tuesday, November 28, 2006 1:43 PM
One option to fix that would be to move the intermodal / shipyard spur towards the "right" and set the intermodal tower in the middle of the wye.

Second option being don't approach the intermodal yard at a 45* angle from the main line. Using a more shallow approach would allow you to keep the intermodal line closer to the bottom edge.

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Posted by Dave-the-Train on Tuesday, November 28, 2006 12:31 PM
Subject to getting the intermodal roads in I really like that Graniterailroader. Big Smile [:D]Big Smile [:D]Big Smile [:D]  (It would need the ship to be shifted north as I suggested earlier).   On first sight it looks very good to me... nice long runs into the ladders.  (This alows cars to settle rather than be twisted around). 
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Posted by GraniteRailroader on Monday, November 27, 2006 9:19 PM
I was looking at your plan... and started to fiddle around with it in MS paint....



Perhaps something like that will work. By moving the wye to the "right" and shifting the yard slightly that direction you can add 1 more staging/storage/whatever track on the left, and it gives you more options for how to construct your engine servicing/fuel/maintainance areas.

This space reserved for SpaceMouse's future presidential candidacy advertisements

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Posted by Dave-the-Train on Monday, November 27, 2006 7:51 PM

1st brief response before sleep... serious concern about safety only kicked in more recently with ltigation for injury compensation.  while the County, State and RR police could beat the **** out of union members with something like impunity companies didn't worry too much about safety of this kind.  Working men died to get the conditions we enjoy today... and their spouses and kids lost their livelihood.

2nd... the suggestion to kick the yard tracks out of the main contradicts the previous (more correct) suggestion to minimize tracks from the main.

(Reason for answer now... tonights job blew out Big Smile [:D] Will get back with more).

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Posted by mtrails on Monday, November 27, 2006 6:10 PM

Great points:

1. Due to the fact that this is a club layout, and multiple operation is of interest realistic or not, I chose the compound ladder to provide a few more cars within the yard. Having a simple ladder (such as the one on the right), the last track would have only been just over 3 feet in lenght, vs. the 4 feet achieved.

The playout of operations has been viewed as multi-operational with minimal obstruction, granted it may not follow realistic engineering practices. Obviously, there are many possible solutions for this trackplan, but we have to keep in mind that not everyone is going to operate in a realistic sence, or a concience state for that matter!

2. This layout is a safety hazard! lol Maybe this could teach some members to be more aware.

3. A second caboose track could be installed in the future, and/or a turnout ,lessening the distance from caboose-to-train as drawn. Fortunately, there is some room available for a supply shed. (Thanks for pointing that out!)

4. Yes. good idea. It will be short, but still serve it's purpose. Oh storage, of course!!

5. This is why I joined the forum! Thanks!!

Jeremy

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Posted by exPalaceDog on Monday, November 27, 2006 2:42 PM

1) To keep initial costs and maintenance as low as possible, a railroad will tend to use the simplest track configuration possible. The yard throat at down 4 over 3 looks to complex. It looks like you are trying to use some sort of compound ladder rather then a simple ladder.If you want to use a compound ladder, the track would be happier coming off the throught track.

2) A railroad would use a compound ladder only if the space available was very limited. They force the switchman to constantly cross the tracks which is a safty hazard.

3) If ths yard is at a division point instead of the end of the line, you might want two caboose tracks, one for each division. Since crew assignments are usually on a first in, first out basis, the caboose track will usually be double ended (as you have drawn). Things should be aranged to allow the caboose to be removed from an arriving train and to be placed on a departing train with as little switching as possible. Also note that there will need to be space for shed/s for the caboose supplies such as coal, lamp oil and so on.

4) The turntable should have an over shoot track opposite the entrance track so the engine will not run onto the ground is the hostler fails to stop in time. As long as you have the turntable, while not run a few tracks off it for storage.

5) The fueling area needs two areas, one for deliver of fuel from tank cars to the plant, one for actually feuling the engines.

Have fun

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Posted by mtrails on Sunday, November 26, 2006 11:24 PM

Here is the optimum trackplan I have come up with:

For the space given, and operations sought, this is the best trackplan within minimal variable limits. Having a main yard on the layout, some of the other suggestions to be included (such as a sanding tower, etc.) can be instilled within the main yard.

Note: as previously mentioned, as the club layout is modular, these modules are made for each other, and not intended to inter-change with others. The 1'x8' main module is the only inter-changeable module in this circumstance, without the wye and yard(s) connection for continuous operation.

Thanks again everyone for your input.

Jeremy

 

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Posted by exPalaceDog on Saturday, November 25, 2006 3:44 PM

The Old Dog finds this to be a interesting but mind bending topic.

Also, the Old Dog sees that it made an bad assumption. the "normal" position for a FPL is open/unlocked, not locked as I had thought.

The Old Dog has always thought that one or more interlocking towers or cabins with minature but working mechanical interlocking logic machines would be a very interesting addition to a layout.

For example, one book I have shows the layout for a small through passenger station, just two main tracks, with two sidings off each side with one platform between each pair of sidings. It also includes a right and left cross over on each end. Putting a "working" interlocking tower at end could provide employment for two lever men. The problem would be to provide enough staging to generate enough traffic to make things "interesting".

Have fun

 

Have f

 

 

 

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Posted by Dave-the-Train on Saturday, November 25, 2006 7:54 AM

I got this stuff out of rather a lot of books...

LTC Rolt "Red for Danger" is a basic on UK train smashes... which were the driving force behind most improvements.

Then I have gone through every issue of "The Engineer", "Engineering", "Locomotive, Carriage and Wagon Revue" and several others,plus US Journals I don't recall the names of from their first issues to 1950.  (The US Journals had some years missing Sad [:(]).

I grew up with a railfan Dad who modelled O Gauge.

My Mum's Dad was a tram driver at one stage.

My Maternal Great grandfather was a Guard (Conductor) on the LBSCR,

One of my Great, Great Grandfathers was a Driver on the London and Croydon.

I figure that I never really stood a chance.

I've worked 85% of my career on the railway... that's how I've had time to go through all the books.  A lot of the work is a matter of being there with your ears open... a bit like an airline pilot but not so well paid... they don't even land the things!  I wonder if they read books about planes? Laugh [(-D]

I wouldn't mind writing a book but it is a lot of work.  Also US and UK practice are significantly different and I not only don't know enough about the US yet but don't have a natural "feel" for it.

Also, it's much easier to answer a question than to present the information from cold.  Plus it is easier for you to relate to the answer to the question than to tie theory to what you might want to do.  Even for other people it will be easier to carry ideas across from your example than to go from principles.

On top of that I have a weirdly wired brain that only learns in 3D but, once it has learnt in 3D can play all the games it wants in abstract theory.

How do you get on understanding Isotopes that don't have a constant number of electrons?  I find that most people boggle at them.  To me the isotopes just live in a 3D space doing an extremely random and comples cube dance - which is a square dance in 3D.

One thing I've now learnt to do (since discovering that not everyone thinks in 3D) is to translate between my 3D and "flatworld".

One thing that will hopefully make my notes above easier is for you to

  1.  draw out the baseboard shapes...
  2. put a print of your last plan beside it.
  3. go through the steps I have written out one by one.

I would lay odds that you will come out with something similar to but different from what I have drawn out for you.  (I've e mailed this).  It would be interesting to show them side-by-side on here for others to see.

From you e mail... one thing you could do is to use my Board H approach as a location to plug on cassettes that people can move their trains around on from home to the club.

I hope that you're having fun Cool [8D]

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Posted by Dave-the-Train on Saturday, November 25, 2006 7:04 AM

Old Dog...

Yes, outside an interlocking as well as in it as few connections in the main as possible is the general rule.

Also, where possible, provide sufficient space inside the first switch to get your whole train in out of the way to free up the main and take away the risk of any other train hitting part of the train left out on the main - in the US this was a significant problem with huge long lengths of single line.  In the UK the design practices in place and the BoT requirements made it extremely rare - I expect someone will give me a list of when and where now Smile [:)] -

Something else you want to do if you can is to locate the first switch inside far enough away from the connection to the main so that if anything derails on it it will stay clear of the main track.  With that arrangement you can cut off the derailed car(s) - sometimes using a torch to cut them off and take the train that would otherwise be stuck blocking the main away.  This keeps your main free and you can sort out the mess later.

If you got to "2" above - the FPL bolt withdrawn and the blades in one position but not connected - even the worst signalman should realise that something is wrong because there isn't a manual set of points on the planet that you don't have to "throw".  I'm quite happy to make this extreme claim... (a) I've been on the motive power end of enough points (b) even a set of blades on a ground throw needs some shifting... and even when it is in 100% good condition... (c) manual points on a box not only have the blades to shift but all the rodding run between the lever and the blades... and this is not often straight - including curves, bell cranks, lost motion devices [compensators] - it also needs all the bearing rollers to be true and at least a little lubricated (if you're lucky).  Then ther's weeds Disapprove [V], bits of ballast Disapprove [V], trash Disapprove [V] and any movement that might have occured or been put into the line by adjacent work Disapprove [V]Disapprove [V].  These are all reasons why the BoT made and enforced its restrictions on distance.

In some UK boxes you would find that the lever next to a point lever had a footplate part way up it. (Lever to the left 90% of the time) .  This was for the signalman to put his foot on and shove while he swung the lever.  You always, but always, kept one foot behind you.  Also, if the pull began to stick or didn't make you dropped the pull and/or threw it back.  You did not struggle with it.  Some Censored [censored] points had to be rammed back into the frame.  These were not always the ones that had to be shifted out with weight.  (There's nearly 18 stone of me - 250lbs - Imperial).  If any points were going to have rod breaks these would be the ones... and you'd feel it... you'd almost certainly "nut" the block [instrument] shelf.  You wouldn't have had to call the management... they'd have heard you at the other end of the patch.  That is always assuming that you weren't unconscious or busy spitting out teeth.

I knew of one incident of a broken rod.  At Sutton in Surrey in cold weather the rods for a switch just outside the Box broke.  The signalman came back with so much force that he smashed the manager stood behind him clean through the Box window and only the walkway railings outside stopped him falling onto the track in the shower of wood and glass.  The manager had several ribs broken.

Okay, so some switches were a light pull... an already broken rod would just come out (or go back) way too easily.

If that isn't enough points where there could be any doubt or the signalman couldn't see how they lay from the Box were increasingly detected in one way or another.

Apart from that...

If the route should be straight on a loco may lose the road if it goes into the diverging route too fast.  It would tend to do this rather than proceed on the wrong road and hit something.  If he didn't go into the dirt the engineer would be turning the air very dark blue (with little lightning flashes in it) and pulling up hard.

Moving on...

The FPL bar between the blades is not the same bar as the drive bar(s) that shift the blades.  The FPL bar is a different shape and "passive" in its action... that is the drive bars shift the blades when pushed or pulled by the rodding from the Signalman's efforts in the Box (active action). The Locking bar is carried from one position to the other by the movement of the blades.  The tolerance permitted for the bolt to be able to close is measured in a very few thousandths of an inch.  (In "Clamp Lock" power points anything more than 5th" either side of dead centre is a failure and the switch will not detect and therefore will not allow the interlocking to let anything else happen... which is pretty sensible when a train may pass over it in excess of 100mph).  The FPL does nothing but detect the position of the blades and then hold them in that position.  It does have size and strength because of that holding action.

Back in the Box the Signalman can't move the switch lever while the FPL is locked.  This is not because of the FPL bolt being "In"/locked but because the interlocking in the leverframe will physically block the wrong action.

I hope that all this makes you all feel a lot safer on trains... and more aware of the rubbish they put in the movies.

Smile [:)]

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Posted by mtrails on Friday, November 24, 2006 11:38 PM

Wow, I really appreciate all of the extensive info guys. Thanks so much. Of course, it will take a few times to re-read, and put this plan together.

The wye has been lifted, and we are at a clean slate as of now. I told the guys; "Let's not get in a hurry to do this, we only want to do this once, and it should be the best way possible, if we are going to model the operations we want to see." They aren't too happy with me right now, but I'm doing the legwork for the team, to avoid the problems and downfalls that might occur, from snap decisions and eagerness to play on new track.

I want to extend thanks to Dog for your information about interlocking towers. I personally model modern era, so I never thought about how the purpose they serve and operate. Knowing this information, especially in this circumstance of model railroading, puts a whole new perspective about the aspect of the hobby we all want to achieve. Most of us model what we see, based on basic principles of railroading that we have gathered from our interest, though some of us have never really understood the specific purpose and reasons of the many functions of  the railroad.

And Dave, sorry to present this conundrum of a trackplan, to which has caused you sleep deprivation, sorting the pieces of this intricate puzzle! Smile [:)] Thank You! You're suggestions, based on real life operations are more than anyone could expect. Hey, did you get this stuff out of a book? Did you write the book!?

On behalf of the Yellowstone Valley Model Railroad Club, thank you. I will present our final trackplan, and photos soon.

Jeremy

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Posted by exPalaceDog on Friday, November 24, 2006 7:02 PM
 Dave-the-Train wrote:
 exPalaceDog wrote:

One principle to remember is that railroads will try to limit the number of turnouts, especialy facing point turnouts in their running tracks. They will often put in one siding or spur, then connect the industrial tracks to it rather then the mainline. Each turnout is a possible source of problems. A broken switch rod on a facing point turnout often means a wreck, so a railroad will keep such turnouts to a mininum.

It might be more realistic to provide only two turnouts, one for each direction in the commodities track, The other tracks would then branch off the wye legs.

Have fun

This is correct both sides of the pond... up to a point.

In the above post the Old Dog was thinking of industrial tracks connected to the mainline outside of yard limits, but the prictice would apply to a degree within an interlocking.


 

 Dave-the-Train wrote:

I noticed the comments earlier about pipe runs to operate points manually from a tower.  The distances quoted look like the extended distances for trailing point (switch) connections in the UK.  As far as I recall Facing Points were never permitted beyond 250 yards on manual connections.  To be exact the manual Facing Point Lock (FPL) was restricted to 250 yards from the lever.  A trailing connection could be further out... I think that 350 yards is correct.  (I have it all documented somewhere).

 

Thanks for the info

 Dave-the-Train wrote:

Broken switch rods are very rare.  The rod is steel with a dirty great lump of point/switch blades and connecting rods at one end and a tower man at the other end.  If anything breaks it is far more likely to be the tower operator.  (I know, I've spent a lot of time changing points that have been absolute Censored [censored] to work.  If a rod breaks when you pull you will go flying.  A signal wire (on a manual signal) is bad enough if it breaks - far more common but still rare... and the signal will automatically fail to danger.

 

The old joke is that is why the call them ARMstrong machines 

 Dave-the-Train wrote:

If a rod were to break the blades of a Facing Point/Switch would not prove and so the FPL would be unable to lock the switch and the interlocking would prevent the  protecting signal from being cleared.  For a Trailing point one of two things would happen... either any wheel moving through the switch would force the blade shut and "trail" through the switch OR the mechanical detection between the switch and the protecting signal would not "make" and the signal would not be capable of being cleared. 

 

The FPL is basically a device which inserts a rod into one of two holes in a plate betreen the points, one hole for the straight route, one for the diverging route, if the rod line between the interlock and the turnout should break;

1) The operator still could reverse the lock lever, the rod would withdraw from one of the holes.

2) That would unlock the turnout lever, so the operator could chnage it's position. However, since line is broken, the turn out would NOT change position. The operator might notice that the lever is easier to operate then normal, but would move. Of course, the signal on the switch stand beside the turnout would not change.

3) The operator could then set the lock lever back to normal. Since the points hve NOT moved, this would lock the turnout back in it's original position

4) The home signal other route for the UN/changed turnout could be then cleared since the turnout level is in the correct position, even thought the turnout is NOT.

To prevent that, there would have to be a feed back from the turnout to the tower indicting the actual position of the turnout.

 Dave-the-Train wrote:

Derailments have been relatively more common where the connecting bars between the blades of a switch have either broken or been tampered with.  When these fail to hold the blades the blades are obviously free to flap around in the breeze and cause an accident.

 

Thjis is the situation that Old Dog had in mind when it wrote the above post. Here the operator might NOT be able to rerlock the turnout, but it depend on where the break was in relationship to the locking holes.

Have fun

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