I seem to be in a musing frame of mind today…
On ribbed boxcars: What’s the reasoning and purpose of the ribs? And why are some horizontal (as seen above) and others vertical? Thanks.
Tom
I hope you’re also in a reading frame of mind Tom.[:)]
http://www.riverraisinmodels.com/libraryData/milwhrbox.pdf
Don’t know how they compare to the ExactRail offering, but I obtained two kits from Rib Side Cars.
http://www.ribsidecars.com/
Cheers, the Bear.
One word: Stiffening.
Steve S
That I can undestand, Steve. However, why are some horizontal ribs and others vertical? Wouldn’t the stiffening forces be different on each? Was one advantageous for certain type of cargo over other types of cargo?
I’ll take a look at Bear’s link to see if they address that.
Tom
Hi, Tom
One consideration in designing cars — and highway trailers for that matter — is the abuse these vehicles get at the loading docks. Forklift drivers can be more concerned with getting the job done quickly and may not take the time to perform the task at hand without the occasional scrape, or worse!
So, besides protecting the lading, much of the protective surfaces were designed to glance off any impact from the loading equipment.
Not that this is the only consideration, but it is part of the reason behind the horizontal orientation.
Regards, Ed
I appreciate the comments so far, fellas. From the first link provide by Bear, it appears that the horizontal ribs (produced from 1937-1951) provided two things (See pg. 24):
- Increased carbody strength
- Unobstructed interior space for cargo
Also, from pg. 25, horizontal ribbed boxcars were made in “prefabricated subassemblies” then assembled together. The roof “needed no car body parts to support its individual panels. This maximized the internal capacity while minimizing the tare (tare) weight” [of the boxcar]. It also mentions that any modifications, design changes, and innovations could be made to any of the subassemblies independently from one another.
Thanks again, Bear, for that link. VERY interesting stuff. [:D]
Tom
Ed,
Would that be similar to the use of horizontal metal bracing inside moving vans?
Tom
That’s part of it, Tom.
I’ve been just as curious as you regarding methods of shipping and lading and the evolution of the same over the years.
Lots of those horizontal rails have notches in them for attaching various forms of hardware and strapping. I have found all sorts of “dunnage” when items arrive at my employer’s docks.
Inflatable bags, nifty plastic “shoes” that slip on the end of 2 x 4s and brace the load. Years ago we used to ship and recieve thousands of gas cylinders by rail. Our company would work with the railroads and various shipping companies to try to get the cylinders to their destination without looking like a jumbled mess of toothpicks upon arrival. No such luck! I think a “Do Not Hump” plackard was an invitation to couple onto the car at twenty miles an hour!
I’ll take a look in some of the carbuilding books I have on hand and see if I can find examples of some of the load stabilizer ideas that have come and gone through the years. Pretty interesting stuff.
I know of a company called Evans that was big into this kind of stuff.
Regards, Ed
One consideration in designing cars — and highway trailers for that matter — is the abuse these vehicles get at the loading docks. Forklift drivers can be more concerned with getting the job done quickly and may not take the time to perform the task at hand without the occasional scrape, or worse!
Having operated a forklift for several years I will tell you upfront that’s the best way to get fired under careless operation and you will be subject of losing your OSHA forklift operator certification and nobody wanted to lose their “seat” since the pay grade was shall we say excellent with shift deferential?
Any damage a operator does the company insurance has to pay for that damage and that includes freight cars. The insurance company will raise it rates for every accident.
So, what advantage or use would a vertical ribbed boxcar have over a horizontal one?
Tom
I wonder what the reason for the door design of 40’ double door automobile box car MILW 6675 was. It appears it may have two separate single doors, not a double width door opening. I have never seen or heard of that before. Did any other railroad have a similar design? Also the left door is wider than the right door.
On further study it looks like the wider left hand door has been made even wider by welding an extension to it. In which case the car does have a single wide opening.
Definately a unusual design.
Pure speculation on my part, but none.
While an over simplification, box cars were developed to keep the weather off the cargo, the main load bearing strength being required in the floor and under frame. The sides and roof were only required to be robust enough to withstand the rigours of rail travel and not to collapse on their cargo.
http://www.american-rails.com/boxcars.html
I would suggest that for whatever reason the Design Team at the Milwaukee Road decided that the rib side method of construction not only suited their design philosophy but was also economically sound at that time.
Not that it is important in the greater scheme of things, what I can’t work out is whether the ribs were “pressed” or “rolled”. Rolled would make more sense, to me, because they could just cut the length required, be it for a passenger car, boxcar, or caboose. The downfall to my rolled argument is that by using a press the ends would be “sealed” by the process.
Cheers, the Bear.[:)]
A friend did a close examination of the design several years ago in preparation for doing the patterns for Sunshine’s resin kit for the Milwaukee Road cars. He examined original construction drawings and made a visit to the Illinois Railway Museum to do a first-hand examination of the cars. I don’t know whether he ever determined anything about the structural strength issues. The edges of each panel were formed into a shape that would interlock with the adjoining panel with minimal use of fasteners.
Tom
Much of the reason for these variations in freight cars lies with experimentation and opinion rather than any objective advantage. Different roads’ engineering/mechanical people came up with different ways to design cars, and if they were successful, thousands of a particular design could be built. The originators often felt a sense of pride in developing something unique that worked, regardless of whether there was any demonstrable improvement over some other idea. Something like the MILW rib-side cars could be welcomed as part of the corporate identity.
In many cases, other roads don’t see the same advantages and don’t copy the design. Baltimore & Ohio liked their “wagon top” cars, but nobody else really did, to cite another example.
In some instances, a railroad would persevere with a particular design out of apparent stubborness, even after that design proved inferior. Pennsy’s 2D-F8 truck had weak sideframe castings which were prone to cracking around the spring box, but Pennsy continued to manufacture it after better sideframes were developed by others.
Freight car manufacturers also came up with their own ways of doing things, which may or may not have been better than what others did. Pullman Standard had their own unique ends and roofs. They weren’t necessarily better or worse than what another builder like ACF used, just different.
From ORER, the door opening for this car is listed as 12’ 5" wide. It does have a “double width door opening”.
Ed
If you are also talking about wood sided as well as steel, they may not be “Ribbed” but rather Out sided braced single sheathed" boxcars, where the sheathing is on the inside of the car affording a smoother interior wall, and having the wall framing on the outside.
Some cars, particularly refers, were double sheathed, and the wall framing was completely hidden, but still there.
The only horizontal interior bracing that I ever saw on furniture, dry or refer vans was either a raised padded rail(in furniture vans) that a rope or strap could be passed between the rail and wall for securing the load, or “E-Rail” that had slots, usually vertically oriented, that straps or bars could lock into.
“Logistics Posts” are typically arranged vertically, with the slots also vertically oriented, the slots in these are identical to “E Rail” and accept standard straps, but are also used with “Decking Bars” to create multi-level decks in furntiure and other vans to maximize the loading of the cargo space.
As with anything there are exceptions, and where I work now, we have two “Squeeze” trailers that have horizontal logistics rail(4 rows per wall). These are very specialized trailers that we haul large blocks (typically 40"Thick x 86"Wide x 109"Long) of Poly Urethane foam in. The trailers have a hydraulicly driven chain drive inside that power a “Tower” on either side of the trailer. Typically 15 “Buns” are loaded into a 53’ trailer, then reinforced aluminum panels(Doors) are placed against the last bun, a pair of heavy duty aluminum I Beams are placed across the doors between the towers, and the towers are advanced until the machinery can no longer compress the foam any further, then decking bars are placed in the logistics rails, and the towers backed off to the rear of the trailer and the I Beams removed and another set of buns, typically 11 or 12 in the second squeeze, the p
There’s been some talk in this column about “vertical” ribs on freight/box cars. I’d sure like to see an example. The only one that comes to mind for me in Pennsy’s G32C gons:
In this case, you’ll note that the ribs span the smaller dimension of the panels.
When ribs are impressed in metal for strengthening a panel, it is best to have the ribs span the narrower distance. For a boxcar that commonly has framing members at the top and bottom of the sides and has vertical posts between the two, it would make no sense for vertical ribs in the side panels because they’d be spanning about 10 feet instead of maybe 2 feet. If there were also horizontal structural elements spaced less than 2 feet apart, vertical strengthening ribs could make sense.
As Doug has just mentioned, there’s lotsa boxcars out there with vertical elements visible. Those are commonly called posts, not ribs. They are NOT stamped into the side sheets as they are in the Milwaukee car under discussion.
With the Milwaukee boxcars, the side panels are certainly interesting. They were made up of sheet steel pieces 13’ 11" long and about 18" wide (tall). There was a rib running along the bottom of each sheet 1 3/4" up. When installed, that rib covered the attachment points of the sheet below, which were 1 3/4" from the top. It appears that the sheets were riveted or bolted to the vertical posts of the car. Those posts were spaced at about 28" apart, much closer together than typical boxcars. I have the impression that the lower edge of a piece was continuously welded along the seam with the piece below after assembly.
So, besides stiffening the side sheets, the rib also covered over the mounting projection of the panel below it. And it kept that
Ed,
Sorry for the incorrect and nebulous terminology on my part.
When I was referring to “vertical” ribs I was thinking of the pronouced ribs on these later-era MILW boxcars,
which appear to be similar to the ones found on these covered hoppers;
NOT the one’s found on the older 6- & 8-panel outside braced wood boxcars:
Tom
The later cars are basically off-the-shelf Pullman Standard designs with exterior posts between the flat side sheets. Numerous customers bought them, in several variations with different cubic capacities. Other manufacturers use an almost identical arrangement.
The earlier cars with the horizontal ribs were an in-house MILW design, built by their own shiops.
Tom,
Gotcha.
On the modern cars, those verticals are doing two things. They’re keeping the roof and the underframe apart. Yes, apart. And they are also keeping the side sheets in one plane, because the sides contribute to the strength and rigidity of the car. Those side posts are acting very much like the ribs you see on the side of girder bridges. Without the side posts, the car would fall apart. With a load in a train, for sure. Maybe just sitting empty on a siding would be OK.
“Regular” old boxcars–the generic steel ones from the '40’s–did the same thing. It’s just that they had the posts on the inside, where they didn’t show. And then the inside of the car was covered with wood. By going to the modern version, you don’t need that wood lining anymore, to present a smooth interior wall.
That last one you show is the wild card. THAT one does NOT use the side sheathing for strength. Those wood planks could all fall off the car, and it would still work great. Though the load would be perilously exposed.
And I’ll also throw in the “double-sheathed” cars. Those go WAY back. They’re pretty much like the oldie we just talked about. Except they covered over the framing that you see with (non-structural) wood. Also, said framing tended to be wood. And needed the outer sheath to keep the weather off.
Ed