BN7150 SD70Dude, your remark is an opinion. If not, please tell me the source. I strongly believe the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks. Kotaro Kuriu
SD70Dude, your remark is an opinion. If not, please tell me the source. I strongly believe the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks.
Kotaro Kuriu
Since you aren't familiar with me and I don't visit this part of the forum much, I'll explain the rationale behind my "opinion", and give some background on myself. (I had read the text of the orders that were subsequently linked, but chose not to add the links to my post)
I work for Canadian National as a conductor and locomotive engineer, depending on where my seniority puts me at any given time. I've run trains on some lines with very steep grades.
The timetable footnotes for those lines still contain a requirement for retainers to be used when descending the grades, unless the lead locomotive is equipped with a functioning pressure-maintaining automatic brake valve (which is pretty much every locomotive these days). Dynamic braking was not absolutely required on these lines until about 2008 (see below).
CN continued ordering new road locomotives without DB until the early 1980s (no DB on the HR-616's), and ordered a small minority of their previous road units with it (some SD40's and SD40-2W's). These units were supposed to be assigned to unit trains on the steeply graded lines I mentioned, but this did not always happen and trains would sometimes operate there without DB right up until about 2008, when our operating rules were changed in the aftermath of a fatal runaway on the former BC Rail line north of Lillooet.
We have one train that still requires retainers on each trip, the only such remaining case on CN's western Canada lines. But they are not for our train handling purposes, rather they are used so the customer to load this unit train on a 2.4% grade by themselves without any locomotives attached. We set the retainers while spotting the empty train, and knock them down after picking up the loads, so I can honestly say I've used retainers in real life.
Greetings from Alberta
-an Articulate Malcontent
OvermodWe are just now seeing an emphasis on truly safe slip and fall protection when working on the tops of equipment
Look at all the fall protection devices where cars or locomotives have to be loaded or serviced from above. Elaborate beams and trolley systems are in place with the worker wearing fall protection harnesses attached to same.
This was unheard of even fifteen or-so years ago.
Regards, Ed
BN7150I think the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks, is that correct?
As noted, it was likely the development of pressure-maintaining rather than use of DB that led to global change in interchange configuration of cars. Remember that DB was an extra-cost option and many roads did not provide it consistently or at all. Subsequent experience with composite brakeshoes has caused use of DB for train control on long severe downgrades to be reduced; speed now has to be kept below safe recovery limit for brake fade (about 23mph on some of the ex-B&O Allegheny-crossing grades, for instance) as if the DB were to fail at or above that speed the train would easily accelerate to unrecoverability.
I believe the slip and fall protection is mentioned in the legislation describing the roofwalk ban. We are just now seeing an emphasis on truly safe slip and fall protection when working on the tops of equipment (e.g. on large preserved steam locomotives) and it can be astoundingly expensive and cumbersome... but the first life it saves 'pays for all' in a sense. The thought of building something comparable for interchange cars running in normal service... among other things it would make practical ECP buildout and running conversion look cheap!
BN7150By the way, you can only walk on the roofwalk when the train is stopped. It's difficult to stay also on it while the train is moving.
Before the advent of the Westinghouse automatic air brake the roof walk was necessary so the brakeman could climb the caboose ladder or climb out of the cupola and access the hand brake wheel on each individual car in order to slow or stop the train.
Likewise the head-brakeman had to work his way back from the locomotive (some railroads had a "house" on the tender deck for the brakeman to ride, and set or release each car's hand brake.
Origination of the name brakeman. https://en.wikipedia.org/wiki/Brakeman
BN7150They were not on the passenger cars.
On passenger cars the brakeman could walk through the cars and set the brakes on each end platform.
Yes, it was a dangerous job.
The roofwalk remained a fixture even after the advent of the automatic air brake. There were occasional times a train was stopped on a bridge. The crew, if they had to walk the train, could use the roof walk if there was no walkway on the bridge(s). Snow could pose another problem that walking the roof would overcome.
Usually the train was stopped when retainers were set but a brakeman could use the roofwalk to go from car-to-car in order to set the required number of retainer valves, which were usually located high on the car, by walking the car tops. Saved a lot of ladder climbing.
SantaFe_Brakeman by Edmund, on Flickr
Summit, California. The brakeman opening the retainer valve on a car on the Atchison, Topeka and Santa Fe Railroad between Barstow and San Bernardino, California. From here to San Bernardino is one long downgrade of more than 2700 feet.
Swing brakeman riding on top of the Santa Fe Railroad train. Brakeman ride the trains in this way during the entire descent from summit to San Bernardino. Delano, Jack, photographer, 1943
Read the comments here for some insight from railroaders concerning roofwalks:
http://industrialscenery.blogspot.com/2015/07/handbrakes-and-brakemen-walkways.html
Rob, thank you for your knowledge of bleed rods.
Now, about the roofwalks. They were not on the passenger cars. They have never been installed in the UK, the continent of Europe, and here in Japan, except for special purposes. The old North American freight cars only. Of course they were dangerous even in the 19th century. So why did roofwalks been adopted? At that time, they were necessary to be set up at the expense of trainman safety and at an extra cost. Because the problem was resolved in 1966, they no longer were needed. Improving safety is very important but only a secondary reason. Isn't it proper to think so?
By the way, you can only walk on the roofwalk when the train is stopped. It's difficult to stay also on it while the train is moving.
BN7150SD70Dude, your remark is an opinion. If not, please tell me the source. I strongly believe the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks.
I'll offer another "opinion" from personal observation.
I believe the widespread use of the two-way radio was another innovation that led to the eventual removal of roof walks. Yes, the safety issue was the primary goal but the use of radios made the adoption more feasible.
There weren't that many radios to go around back then and the cash-strapped Penn Central didn't seem too eager to buy very many. The portable units were still as big as a lunch box. Not very "portable" when humping a cut of cars.
I've watched yard crews in the late '60s and through the '70s and often, when hand-signalling was the only means of communicating with the engineer, a brakeman or even two, would sometimes have to climb the middle of a cut in order to relay hand signals when visibility was tight.
I recall, too, that when the move was completed, they liked to see how high they could toss a lighted fusee from the roof
BN7150I strongly believe the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks.
The reason was most definitely safety. The Federal Resgister has a history of safety appliance regulation describing why changes over time were necessary. https://www.federalregister.gov/documents/2010/07/02/2010-16153/railroad-safety-appliance-standards-miscellaneous-revisions
The regulatory changes were years in the making, spurred by the desire to reduce injuries. As indicated in the above linked source:
The Railroad Safety Appliance Standards encompassed in part 231 serve the purpose of increasing railroad safety by identifying the applicable safety appliance requirements for various individual car types. See, e.g., 49 CFR 231.1, box and other house cars built or placed into service before October 1, 1966.
Widespread use of dynamic braking in the diesel era, along with improvements in brake valve design, obviated the perceived need for running boards, but into and of itself did not force a change to the rules.
I found the following picture on the net. Is there anyone who can explain this?
That appears to be a bleed rod. Definition here https://www.csx.com/index.cfm/about-us/company-overview/railroad-dictionary/?i=B . More on air brake function here https://wplives.org/forms_and_documents/Air_Brake_Principles.pdf .
Rob Spangler
Thank you Rick for the model example. When did this recreate the era? Is the rolling stock still equipped with the Retainer Valve? I found the following picture on the net. Is there anyone who can explain this?
Quoted from BrassTrains.com (CROWN CUSTOM IMPORTS, BAR BANGOR & AROOSTOOK STATE OF MAINE BOX CAR - FP -#2445)
For anyone interested in the applicable safety appliance regulations, here's the link https://www.law.cornell.edu/cfr/text/49/231.27 .
DSC01084 by wp8thsub, on Flickr
DSC01084
Modified cars were required to have a warning label, usually yellow, stating "keep off roof no running board" or similar, to be placed adjacent to the B end ladders (provided they remained at full height). These are available from decal suppliers including Microscale and others.
Relocating the retainer valve was not a requirement.
BN7150 I think the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks, is that correct?
I think the widespread use of dynamic braking in diesel locomotives is the reason for the removal of the roof walks, is that correct?
Roofwalks went away because it was finally decided that expecting trainmen to walk on top of railcars without fall protection was unreasonable and unsafe.
The invention of the pressure-maintaining automatic brake valve (standard by the late 1950s) meant that retainers were no longer needed to safely descend most steep grades. Dynamic braking helps a lot too, but a number of railroads did not order their diesels with it.
BN7150 Unfortunately the instructions are for the original PS-1. It could be near the control valve, as Chris says. Does anyone have a model with a retainer valve under the floor?
Unfortunately the instructions are for the original PS-1. It could be near the control valve, as Chris says. Does anyone have a model with a retainer valve under the floor?
Not a boxcar, but here is a picture of a gondola I made with the retainer valve hung under the side of the car with piping to the ABD Valve.
The retainer valve is at the top left in the picture.
Rick Jesionowski
Rule 1: This is my railroad.
Rule 2: I make the rules.
Rule 3: Illuminating discussion of prototype history, equipment and operating practices is always welcome, but in the event of visitor-perceived anacronisms, detail descrepancies or operating errors, consult RULE 1!
wp8thsub While the model has no running boards, Intermountain leaves the A end ladders at full height instead of lowering them to four rungs. Fortunately this problem is easy to fix. Compared to the prototype, note the location of the consolidated stencil is off, and the ACI label is omitted. There are some missing grab irons on the ends, and the roof at the B end.
While the model has no running boards, Intermountain leaves the A end ladders at full height instead of lowering them to four rungs. Fortunately this problem is easy to fix. Compared to the prototype, note the location of the consolidated stencil is off, and the ACI label is omitted. There are some missing grab irons on the ends, and the roof at the B end.
Most railroads did not lower the ladders and brakewheel on the B end of the car as it was not cost effective and they were allowed to have the high mounted ladders and brakewheel on the B end of the car, it was a simple cut job on the A end to removed the extra height on the ladders. They still had to have a grab on the roof for the brakeman to hold onto.
By the way there is no way to know if they lowered the B end ladder and brake wheel since the picture was on the right side of the car and you can't see where the brake wheel is in the picture.
Most of the cars I have seen pictures of have the high mounted ladders and brakewheel on the B end of the car with no running boards.
Rob, GREAT! The next two photos are InterMontain's 12-panel boxcar, modified 10 years ago. I failed to match the BN green.
The followings are the material of the Car & Locomotive Cyclopedia 1974 edition that I referred to at that time (click to enlarge). I had no knowledge of Retainer Valves.
BN7150By the way, I got an InterMountain 40-ft PS-1 today. This ATSF car is removed-roofwalk specification.
That's typical for Intermountain, and for some other manufacturers as well. The lettering may be mostly based on a prototype, but the car itself still has the same standardized details as everything else they make. There's even a prototype photo of this number online http://rr-fallenflags.org/atsf/atsf31679.jpg ,
The retainer valve!
By the way for all you who commented it is not a triple valve the proper term is ABD valve.
Thank you everyone for your comments. I think this kit with too many bad spots may have to start with a re-paint..........
By the way, I got an InterMountain 40-ft PS-1 today. This ATSF car is removed-roofwalk specification. I show you some pictures. Click to enlarge.
The R-side. There is no notation of "RETAINER VALVE".
The L-side. There is a notation of "RETAINER VALVE".
Under the floor. There is no "RETAINER VALVE".
The B-end. What's next to the handbrake wheel? :-)
BN7150Does anyone have a model with a retainer valve under the floor?
I finished this car not too long ago from a Moloco undecorated kit, and configured the underframe details based on prototype photos and diagrams where possible.
20201109_215455 by wp8thsub, on Flickr
20201109_215455
The retainer valve is located in a housing just to the left of the door. Visible just to the left of this is the silhouette of the pipe that connects it to the ABD valve. These SP cars used housings larger than most, but the location is typical - somewhere along the side sill close to the ABD valve, as that's where the piping must connect.
The above photo is from Moloco's site at https://www.molocotrains.com/collections/freight-cars/products/51015-sp-delivery-new-11-62-pcf-50-rbl-plt-b-10-0-offset-door-df-b-loaders-b-70-10?variant=37588813447346 , showing the as-built configuration of the same class of car. The original retainer valve location was here on the B end, just above and to the left of the crossover platform. Since the retainer valves were often moved to the side after a car was built, locations could vary, and each railroad may have had its own idea about where to move the components.
Incidentally, SOO had an odd practice of keeping part of the running board (on the B end) when the rest was removed and the A end ladders shortened. This photo from http://rr-fallenflags.org/soo/soo-frt.htm shows a different type of car, but the same configuration was found on many SOO boxcars. It's an interesting quirk to model.
Usually when the retainer is under the floor it will be located near the control valve, called the triple valve on the instruction sheet.
Mark Vinski
PS: Chris, don't point out the many mistakes in this kit. Even if that is not the case, it is difficult to fix the defective parts, and the motivation to assemble is waning. First, this car number seem to be not PS-1.
Kotaro Kuriu, Kyoto, Japan
On a lot of older cars it was actually on the end by the hand brake. (Look for a pipe and valve mounted beside the brake.)
Later it was just on the underframe close to the brake valves with a control rod to one side. (If no valve on end, look for the "triple" valve on the underframe. The retainer might not be modelled, but would be just to the side of this.)
Other decoration notes: the two-panel black consolidated stencil (incorrectly "lube plates") was applied between 1974-81 after which it was replaced by the new three-panel standard, and the yellow dot on black square (U-1 wheel dot) was a 1978 inspection program. Lack of ACI bar code label would put it after 1977 (although this is a decal often left off by some manufacturers). The (current) decoration of the car would therefore put the repaint somewhere around 1977-79. (Add ACI label to push it earlier.) Running boards could be removed starting in 1966. I can't read the shop code on the car clearly though with the size of the photo... is it '62? (This would be easy to update to a desired date with some data stencils.)
Chris van der Heide
My Algoma Central Railway Modeling Blog
The quick and naive answer is 'look underneath for brake piping'. The retainer is a valve that holds a certain brake-cylinder pressure independent of trainline release and recharge, and there should be brake equipment visible at the place the notice appears.
I'm about to assemble a pre-painted boxcar kit that was Soo Line 40-ft PS-1 repainted in the 1980s (removed roof walk). The print plate on both sides is the same, so some symbols need to be removed. What is worrisome is the notation of "RETAINING VALVE". Which side is this correct? Please give me your advice.