Hi Everyone!
Does anyone have or know of pictures of what the mechanical linkages on the inside of the first floor of a yard tower would look like. I am modeling in HO and I have the Atlas control tower. I have done a reasonable mock up of the top level with levers and desks etc., but since the tower will be at the forefront of my layout I thought a few more details might be appropriate.
Thanks
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
It would look like an empty room.
There are no "mechanisms" in yard towers to control switches. Yard switches are all hand operated.
Interlocking towers at junctions have mechanisms to control switches, but they are interlockings, not yards. If you want to see those look for pictures of interlocking towers, interlocking machines, or interlocking rodding.
Dave H.
Dave H. Painted side goes up. My website : wnbranch.com
dehusman
Thanks for the clarification. My railroad terminology is somewhat lacking.
OK - to clarify, what would the lower room of an interlocking tower look like? Also, what would be seen outside of the tower in terms of control mechanisms. I have seen one picture depicting lots of mechanical stuff outside of a tower but I can't find that picture.
I just re-read your answer and discovered where I am going wrong. I am indeed modeling a yard tower, not a junction. I have already put a table and chairs in the lower level of the Atlas tower so if I understand you correctly that is OK.
Problem solved.
Thanks again for your insight.
now that we know we are talking about an interlocking tower, the last time i was in the lower lever of one, it contained all the signal maintainer's work bench, desk, tools, equipment, spare parts, lockers, rest room, lunch table and a whole bunch of batteries to supply current to the signals and plant in the event the city power went out. sometimes this space was shared with the track supervisor and his group or the radio maintainer.
grizlump
Dave,
The Atlas model is an Interlocking Tower. That said, it could fitted out to be a Yard Tower. The upper floor might have desks for the Yardmaster and the Yard Clerks. The lower ground area would have lockers for the Yard Crews. My Yard Office is small single level structure(only have a 4 track yard).. The depot is much larger and maybe the Yard Master and the Yard Clerks should be there. But the the building is near the 'lead' and just looks good!
BTW, if you were modeling an Interlocker - AMB has a nice kit of the 'Armstrong' levers. What goes down on the 1st story is the actual mechanical 'locking bed'(actually hangs down from those levers upstairs). Also batteries for the telephone/ telegraph equipment, and a coal burning stove that needed to be 'stoked' every few hours. I worked in a CB&Q tower for about 6 weeks, until I got a chance to go in road service. I did that until I got drafted, and never went back to the railroad when I got out of the Army. The old Oakland Ave Tower had seen better days, and really rocked when a fast passenger train went by!
http://www.laserkit.com/laserkit.htm
Scroll down about 2/3rd's of the way to see it....
Jim
Modeling BNSF and Milwaukee Road in SW Wisconsin
If you are looking for interior photos of interlocking towers and the outside piping on armstong levered equipped ones, I suggest you get a copy of Jeff Wilson's Model Railroader Guide to Junctions published by Kalmbach. There are a lot of great modeling tips in this one. Bill Darnaby has modeled and written on the subject and some of his material is in the book too.
As an aside, there were some towers in Europe I believe that controlled yard trackage and some interlocking towers in the U.S. controlled a maze of trackage in large city stations located in St. Louis and Chicago for example, but they were still technically interlocking towers. Also hump yard towers not only control the retarders but the tracks that the cars roll into. But this is not done with levers.
I am building a 40 lever interlocking plant on my layout with Hump Yard Purveyance armstrong levers. Right now I am just controlling the switches but eventually will phase in the semaphore signals, derails and facing point lock levers as the levers are expensive, even when purchased in bulk. I am using slide switches rather than the bicycle cable they provide in their kits. I will eventually add Bruce Chub's circuitry with a computer hidden in the background to interlock the set-up and control the signal aspects. I am not interested in building the actual mechanical tappets etc or buying one built for me.
Dave,Stop! Halt! Cease and desist.
First there are several excellent options for a yard office.
My favorite is this one that been produce by several manufacturers.
http://tycotrain.tripod.com/tycokits/id19.html
While its advertise as a interlocker it can be used as a older yard office with a locker/ break room for the yard crew(the bottom door) while the office is on the top floor..I don't use the electrical cabinets.
My favorite modern yard office is this one made by BLMA.
http://www.blmamodels.com/images/store/4300a.jpg
Here is another option.
http://www.walthers.com/exec/productinfo/933-2830
For smaller yards you may want to consider this office.
http://www.walthers.com/exec/productinfo/933-3517
Larry
Conductor.
Summerset Ry.
"Stay Alert, Don't get hurt Safety First!"
Dear Brakie (and anybody else who'd be good enough to chime in),
I got my yard office, so now I want to ask a really goofy question: what does a yard tower do, what's it look like, and what should be in it on which floors if there are more than one (I would presume you'd have to be up high enough on a second or third floor to see everything in the yard)....say you're modelling 50-60s, maybe some early 70s?
What the heck are they doing in an old yard tower anyway?
I'm guessing from what I've read so far that levers and switch controllers wouldn't be in it?
Thanks.
The St. Francis Consolidated Railroad of the Colorado Rockies
Denver, Colorado
The Chicago Great Western has a two story yard office at Stockton, Illinois that looked much like an interlocking tower. There were other examples on other railroads.
http://www.railpictures.net/viewphoto.php?id=260898
Most yard offices aren't towers, they are ground level buildings. Basically the yardmaster is directing teh switching operations in the yard. The yardmaster is deciding which track inbound trains are going to. Clerks are making track lists and sorting waybills. Yardmasters take the track lists and decide which job will switch them, how they will switch them, which tracks the cars will go into, then he marks up a switch list which is given to the switch crews.
After the switching is done the clerks get the switch ist, revise the track lists, and give new track lists to the yardmaster. He decides when to build the outbound trains, which job will build them, which cars will go on the train, how it will be doubled up and what track it will be built in. He marks up lists and are given to the switch crews.
The crews build the train and give the switch lists to the clerks. The clerks write up the outbound train list and get the waybills together. The yardmaster tells the carmen to inspect the train and tells the dispatch office or crew calleers to call the crew. The carmen inspect the train and tell the yardmaster. The Yardmaster calls the roundhouse than they bring out the power. The operator clears the train orders for the train. The outbound crew reports for duty and gets their lists, bills and orders. They get on the train, the yardmaster tells them what route to take out of the yard.
Repeat as necessary.
Often it was the office for the yardmaster if he wasn't located in another administrative building. How about a real example? I can speak for the Wabash at Montpelier, Ohio in the steam era. The Wabash had a west yard office and an east yard office.This was common with a big yard. The offices were a place for an outbound conductor to pick up waybills, a list of cars in the train and perhaps what needed to be switched at the next station out on the line. (As to other switching by road trains out on the main, that info would be relayed by station agents up and down the line to each other by telegraph or by phone and then passed on to the train crew with written messages by hand or included with orders in the hoop on the fly.) The yardmaster also had clerks that who would, for example, track the cars as they came in or just inventory them. At Montpelier, the "car knockers" (car inspectors) had their own building. I have an acquaintance that worked as a clerk for a short while. He did not like walking between the cars in the yard.
dehusman It would look like an empty room. There are no "mechanisms" in yard towers to control switches. Yard switches are all hand operated. Interlocking towers at junctions have mechanisms to control switches, but they are interlockings, not yards. If you want to see those look for pictures of interlocking towers, interlocking machines, or interlocking rodding. Dave H.
Okay, so how about educating the uneducatable. There is normally a tower of some sort at the top of the hump yard lead. I'm pretty sure that they had provisions to throw turnouts as the cars ran down the hump. Would we not call this a yard tower?
On the other hand, there were also towers at the throat of large, busy, passenger terminals with provision to throw turnouts to align trains to the proper terminal tracks. I guess those terminal tracks would not be properly called yard tracks, but what would those tracks at the terminal throat be called? Would that be called an interlocking, and the tower called an interlocking tower? Or would the carknockers at that facility just call it the yard tower?
maxman Okay, so how about educating the uneducatable. There is normally a tower of some sort at the top of the hump yard lead. I'm pretty sure that they had provisions to throw turnouts as the cars ran down the hump. Would we not call this a yard tower?
Yes that would be a tower (or towers) and there would be some sort of mechanism to control the switches. Since the 1960's or 1970's it would be a large grey cabinet filled with relays, attached to a computer.
Interlocking tower.
Thanks everyone for all the information. These forums are great for finding out what you thought you knew but didn't.
Here are my conclusions based on your answers.
First, the term 'yard tower' is a bit of a misnomer. More accurately it should be described as a 'yard office'. Whether or not it has two stories is up to the modeler, but one story would seem to have been more common.
Second, there weren't any Armstrong levers in the two story yard offices. Turnout control was done at the turnouts by the yard crews. The yard office provided clerical control, not mechanical.
Third, interlocking towers would have been used at junctions etc. where taking the time for the train crews to stop and switch the turnouts would have been inefficient.
Do I have this right yet?
i think the word many of you are searching for in reference to the interlocking switches and signals that are controled from a central location is "plant". at least that is all i ever heared it referred to during my railroad years.
the interlocking plant might be controlled by levers and rods, electric switch motors and signals through relays, or as i recall, the switches at St Louis Union Station controlled from Perry Tower were steam powered, perhaps later on converted to pneumatic but i am not sure about the conversion.
before the computer age, towers at strategic locations in large hump yards contained retarder operators who kept an eye on the speed of cars coming down the hill and how much room was left in the track into which each car or cut was going. this man controlled the retarders to slow the cars down to a safe coupling speed 2-4 mph.
the last two yard towers i was in, and i wish i had paid more attention, were at the A&S at E St Louis and the Big Four yard at Avon (Indianapolis). both had a man at a desk/control pannel where he worked from switch lists and lined the swiches with those controls to divert cars into the proper tracks. at both of those instalations, i think the retarding was computer controlled with sensors and or radar to determine amount of clear track, car speed, and amount of retardation necessary to insure something less than a hard collision upon coupling.
all of this is pretty much un-necessary with flat switching unless the yardmaster just wants to keep a close eye on things. the yard conductor or foreman usually give the signals to the engineer while the head brakeman plays pin puller and runs along side the cut when the cars are kicked. meawhile the rear man or field man lines the switches for the designated track as each car or cut comes rolling down the lead. a good crew can have cars rolling in 4 or 5 tracks at the same time but few can keep up that pace for very long.
Dave:
I think you pretty much have it but the reason that interlocking existed were for safety. An interlocking would not allow a conflicting routing that would cause a collision, that is if the trains were following signals indications correctly.
hon30critter First, the term 'yard tower' is a bit of a misnomer. More accurately it should be described as a 'yard office'. Whether or not it has two stories is up to the modeler, but one story would seem to have been more common.
If the structure is more than one story its a "tower". The place the clerks are located is the yard office. The yardmaster can be co-located with the clerks or he can be in a separate building. A big yard can have several towers, a yard office and several crew "shanties". Since there are lots of variations on how you can locate people, the definitiions of the various buildings is not a hard and fast rule.
Also note that yardmaster towers were also 3, 4 or 5 stories tall.
There are two types of interlockings, manual or automatic. Manual interlockings have a human being operating the switches and signals. Automatic have circuitry controlling the signals.
Manual interlockings can be controlled by an operator at the location or remotely, the operator can be in a tower or not.. Normally those locations with "armstrong" levers, that are purely mechanical will be in towers. Those that are electrocmechanical or pnuematic don't necessarily have to be in towers.
"I have an acquaintance that worked as a clerk for a short while. He did not like walking between the cars in the yard."
i got a chuckle out of that one. wonder what he thought clerks did. he should have been in the old NKP yard at Madison Illinois. it was formerly a narrow gauge line and some of those guys said a big man had to turn sideways because the tracks were so close together.
worst thing for me was when i was between two tracks and they were both moving at the same time. some people just can not handle that and i was one of them, only solution was to mount the side of one cut and ride it out or get down and sit on the ground until one of them was gone.
Although I come from a very different tradition I might be able to add a little historical information.
A lot of very early rail equipment development occurred in the UK and the ideas if not the physical parts were exported. Other countries put their own spin on these things... subsequently the USA, particularly Westinghouse, developed equipment and marketed it all round the world.
(One thing that US and UK equipment have in common is what Americans call an Armstrong frame in a raised operating floor which operates both signals and switches. A number of european systems use (or used) a different kind of mechanical apparatus working a double [steel] wire system to operate their signals).
The way that this applies to the OP as I see it is first to recognise that difference between an interlocking and several other situations.
An interlocking combines at least the remote control of switches (and sometimes derails) and usually the related fixed signals.
In the very early years there was no link at all between switches and signals. This meant that false indications could be given by the signals. The solution was to interlock them mechanically... because electric and subsequent systems hadn't been invented. (In fact they were still figuring out how to make good, reliable insulated electric wire of suitable size).
A mechanical interlocking frame is far more usually set in a raised operating floor. This is because most designs are pretty much like icebergs - all you see is the top bit sticking up through the operating floor.
The bit that you see is the levers (armstrong levers) sticking up through what we call the quadrant or sector plates usually set flat in the floor.
The quadrant plates are usually the radius of the circle described from the pivot point of the lever down below in what we call the "underframe". There are variations but the principle stays the same. The greatest number of quadrant plates have a deep notch at the back and at the front of the travel of the lever. This notch receives the lever latch on its rod.
The armstrong lever itself has a thinner rod on the front or back with a lever or stirrup at the top. This latch rod is spring driven downwards causing it to always try to push the latch on the lower end down into the notch. To work the lever in either direction the small lever or stirrup at the top of the Armstrong lever has to be worked to lift the latch up out of the sector plate to release the main (armstrong) lever to travel. The purpose of the latch is to secure the lever in one position or another so that no accidental movement can occur.
The latch rod sometimes only extends between the lever head and the quadrant plate. Frequently it extends through the sector plate to be linked to other equipment below. I'm not going to go into that.
The main part of the Armstrong lever is below the quadrant plate in a mechanical frame.
The frame below the quadrant plate is more often than not an inverted A. I desribe it this way rather than a V because there is almost always the cross bar to give the frame frot-and back rigidity. The "A"s are lined up side by side with the levers in the direction of throw of the levers. A small frame may have only one at each end larger frames may have them at intervals varying between every six and ten levers. The interval is determined by their age (the strength/reliability of the metal) and other work that they are doing.
So, if we stand in an underframe we will more often see a girder fixed on the floor with the bottom end of the inverted "A"s attached to it. There will then be a shaft secured by the A frames near the bottom running the length of the lever frame with the levers pivoted on it. The upper end of the levers will disappear up through the quadrant plates set in the operating floor over our heads. The upper ends of the "A"s' legs will attach to the underside of the quadrant plates.
The basic lever is about 2.5" x 0.75" in the underframe made of extremely hard steel. (I know - it's very hard work to cut or drill one). Some frames are designed with straight levers while some have L shaped levers... some even have assymetric inverted T shapes with a front and back projection. Most frames have all the levers the same because they are one original design and repairs or additions have been matched. There is sometimes a seperate,subsequent sub frame that can be different. Where these occur they either do not need to be interlocked with the original frame or they are interlocked electrically.
Levers doing heavy mechanical work such as shifting switch blades drive point rodding, In the USA you seem to pretty much only use pipe rodding. Elsewhere other shapes are used as well. These include T shape and (ours) inverted square U shape. Each shape has its own advantages and disadvantages. Solid section was only used in very early years: it is inappropriately heavy.
The straight rods are carried on roller systems according to their design. (I'm pretty sure that Walthers do a US design). They can be curved to some extent but usually make straight runs between levers and right-angled "bell" cranks. They make a solid connection between the switch operators arms and the switch blades.
The rollers, cranks and levers put friction into the system and have to be kept adjusted and lubricated. They have to be kept weed and detritus free as well. Working a badly maintained run is hard work. There are effective maximum distances between the operator and the switch blade. These were defined by law in the UK which explains how our rail stations and yards were set out and how the "signalboxes" were placed. I don't know what if any rules applied in the USA. Two important principles applied. 1. the ability of the smallest operator to correctly and safely shift the switch in both directions at the far end of the rodding run and 2. the reliability of the system without jamming and failures.
Levers doing less heavy work, mainly operating semaphore signals, were attached to multi-stranded steel wires. These made a run from the frame to the signal carried on a different variety of rollers. They could change direction by levers or pulley type wheels. The run had to be maintained in the same way that rod runs had to be.
Signal wire runs could be far longer than point rod runs. Certainly up to 1,000 yards. Long runs included assisting weights. They are not "fun" to work.
With all the weight and friction in the equipment Armstrong levers and their frames have to be solid. Pulling a "heavy" lever is a matter of technique rather than strength.
Okay - that has dealt with the levers and what they shift...
There are several different mechanical ways of interlocking the levers in a frame with each other. The type of locking that became most common around the world is called "tappet" interlocking. It takes several forms. This is because different companies had to avoid infringing other companies patents.
If you stand inside an underframe you will probably see a long black (or grey) metal box running across the levers. This will be the length of the frame, about 4" deep and anythng from about 10" to 24" front to back. They are often set at an angle of about 40 degrees... but they vary. This is the interlocking tray.
The tray is a solid underpart that carries and secures the interlocking bars that cross between the levers. When not being maintained several lengths of thin metal cover usually keep dirt out and the lubricant in.
When the covers are off you can see that (most) interlockings have square or rectangular shafts running across the levers. These intersect at right angles with similar shafts from each lever. Many of the intersections have nothing going on_ there is no need for a control. A number of intersections have a tappet (lump sticking out) on one or other shaft and corresponding cut-outs in an appropriate position on the other shaft. When these are not ingaged movement is permitted. When they engage they prevent any movement at all. Locking trays are tight.
There are many different systems but they all do the same thing and they are all built to extremely close tolerances for mechanical work of their period.
That is the basic frame that you will see in the lower part of an interlocking.
--------------------
Interlocking towers was also use at the throats of major freight and passenger terminals-this eliminated the need to have several switch tenders to line trains in and out of the yard or passenger terminal.
I have described a basic mechanical interlocking with an Armstrong levered frame.
Nothing stays the same.
The practical limitations and maintenance costs of the basic system led to developments. This went on around the world but North America led the way in a number of areas.
I'm not sure if the USA ever tried hydraulic systems to transmit the drive from lever to equipment. The problems were leaks and freezing. I don't know of any systems that were really succesful.
Pneumatic systems met with success before electro-mechanical systems. Again this was largely due to sorting out the insulated electric cable problem. This isn't just the small detail of keeping the electricity in (and not setting fire to the neighbourhood),,, but of preventing vermin from eating the cables. At one time differently insulated cable had to be used depending on whether the local problem was more rats or more squirrels.
Pneumatic systems (like hydraulic) used steel pipes to transmit the power. All that would be seen coming out of the tower would be the pipes. There would be a pump and accumulator building close by. The earliest systems had the valves in the tower. Where either system replaced rods and cables the valves would be attached to the lower end of the levers in the underframe. Some frames had both manual and prseeure systems for a time at least.
From this point on what you would see in an underframe becomes increasingly complicated.
The thing to recall is that the RR had investment in the original plant. The original plant does the job. A lot can be achieved by adding to or amending what is already there. This is more cost effective than complete replacement... up to a point. The question is always at what point replacement becomes effective - and what money is available.
The lower ends of Armstrong levers lend themselves very conveniently to having shaft drives attached to them. This makes it easy to add all sorts of things such as prssure fluid valves, electrical switches, electrical locks and more to them.
This means that each interlocking tower's underframe was not only specific but specific at different dates depending on the latest modification.
When a switch is changed from manual drive to power the external change is in rods to pipework or (later) cables - which may or may not be visible. The internal change in the underframe is some sort of linkage to some sort of valve or switch and the disappearance of the rods - and the hole in the wall for them to run through. This is really good as it makes the tower much warmer in winter! On the operating floor there is a serious need to know the difference between manual levers and power ones. Manuals need various levels of force to shift them. Powers need hardly any. If you put the wrong pull onto a lever you will injure yourself. In the UK we distinguished the difference by cutting the tops off of power levers making them about 6" shorter. I don't know what was done in the USA.
The more an interlocking tower controls power equipment the less it needs Armstrong Levers. This brings about a point of change where the old mechanical frame can be replaced by a more modern system. These varoied from miniature lever frames (Westinghouse among others) to panels with switches on. I daren't even try to go there!
As far as the OP goes the result for the underframe would be that there would be no metal frame, no locking tray and so on. All there would be would be banks of electrical equipment.
The early "drive all the way" pneumatic systems developed into electro-pneumatic systems. Later electro-mechanical became the norm followed by electro-pneumatic. There's different bits of different systems all over the place. ...and that's just the switches! Signals followed the same changes up to the stage where they shifted to colour or position lights. All that light signals need is cables and switches.
Interlocking moved from mechanical to electrical... which initially meant circuits with relays in them and now means micro chips.
Developments have meant that the equipment, particularly the interlocking system, doesn't need to be anywhere near the operator. In fact the operator doesn't need to be anywhere near the track. He or she can be in an office block in a city that doesn't even have any railroads. The "plant" can be in several other cities and the connections can be via satelite.
This leaves a question from the OP of what would be in the bottom part of a tower.
Answer 1. It depends on the date and the RR.
2. By the 70s there could still be a mechanical frame if there had been no cause or money to update it.
3. A mechanical frame could be working a power system with appropriate fittings: almost certainly including batteries somewhere... but they might be in a seperate building (maybe next door).
4. The underframe could be empty or given over to a different use.
5. The whole building could have been replaced with a newer one next to it, nearby or nowhere to be seen. -- Sometimes the original will change use, be preserved or just leave a footprint.
There are probably a whole lot of different options.
Slightly OT In my own experience I have dealt with Westinghouse frames that were installed in new and replacement signalboxes during the second world war. I have also smashed my knuckles a few times with some designs of Westinghouse point (switch) motor.
Back at the OP... While the switches in your yard are likely to have been hand thrown on the ground you might like to consider whether the connection out to the Main track would be a powered switch. This will depend on that switch being connected to an interlocking, in a CTC area or a later system. Communication short of that switch (in clear) would need to be from a phone placed near to it or in the yard office - possibly located in an old local interlocking tower... or by radio more recently...
Dave-the-Train and everyone else:
Thanks for the answers, especially Dave for taking the time to provide all that detailed information. I am modeling in the late 50's so I think it would be safe to say that there are several possibilities which could be deemed realistic.
I have some more thinking to do.
This is more interlocking than Yard Towering, but in regards to what the lower level might look like, google the Haley Tower Historical Society. They have both Haley Tower, which sits on public property now, but is a whopping two or three dozen FEET from where she originally worked in Terre Haute, but she is also joined by Spring Mill Tower. Spring Mill was MILW, and was a true Armstrong, I remember being in there shortly after they moived her and looking down the floorboards next to the Armstrong plant and into the lower level. Don't think I still have tohose pictures. Haley is a bank of horizontal throw levers, and her "basement" was a muddy, dark, room full fo wires and aged electrical boxes. I believe her Society has now throughly cleanerd that up and is better looking, but they might have pictures handy for reference.
-Morgan