They are just different designs by different manufacturers. Has nothing to do with the loading per se.
The corrogations are pressed into the ends to strengthen it. The ealry ends were applied to a "smoothside" car with the posts on the interior so the edges of the ends had to be smooth and straight. When pressing the metal it deforms it and they put the little "darts" in to help keep the edges straight and smooth. When they went to exterior post cars, they no longer needed to wrap the ends around sides and so they went to a cheaper to fabricate "non-terminating" end The size of the corrugations is dependent on the design the particular manufacturer chooses.
"corrugated" ends are normally made a a specific size panel, with multiple panels per end. The advantage of a non-terminating end is that they can be made as one continuous piece and adapted to different height cars more easily.
The same with doors. You could ask what all automobiles don't look the same. Doors are different because there are different manufacturers and each one has a different idea of a better, stronger, cheaper, easier to assemble and repair door.
Dave H. Painted side goes up. My website : wnbranch.com
BN7150Please tell me the welded structure.
Then look at the counterpart on a high-cube car, easily formed on something like a press brake from cheap sheet ... but needing to be welded following the zigzag on both sides to large corner posts. This joint would be difficult with flux-coated rods, nearly impossible with the fusion welding techniques in the '20s (before the use of shielding gas) but with wire-feed gas-shielded welding it would be comparatively simple.
Now add the advances in CNC equipment and industrial robot welding since the '60s and think how simple following the seams at the edges of the end panel might be for even obsolescent computer-driven equipment...
Not as elegant-looking, but very strong and with a long service life.
cv_acr The answer is simply an evolution in welding and car construction methods.
I am very interested in your comments. Please tell me the welded structure. I can understand terms such as fillet welding and HAZ. Unfortunately my imagination lacks grounds.
BN7150n my imagination, the reason is that the loading device has been changed to dunnage. Until then, the back-and-forth sway of the luggage was received by the loading device or the block fixed on the floor. When it becomes dunnage, the total load of one car is applied to both ends. In other words, the car end wall will have to receive the all load as a surface.
No.
Most plain boxcars don't have any "loading devices". (This applies from the very first boxcar ever built, to the modern boxes rolling off production lines today.)
Specially equipped boxcars with loading device such as interior bulkheads, restraint bars, or strap anchors were also a thing long before they moved to the simpler modern ends.
The answer is simply an evolution in welding and car construction methods.
Chris van der Heide
My Algoma Central Railway Modeling Blog
I also want to know the reason for this rapid transition in the 1970s. The blue of the image is Sieco-5077, the brown is PS-5277, and the yellow is ACF-5077 (Crick to enlarge). In my imagination, the reason is that the loading device has been changed to dunnage. Until then, the back-and-forth sway of the luggage was received by the loading device or the block fixed on the floor. When it becomes dunnage, the total load of one car is applied to both ends. In other words, the car end wall will have to receive the all load as a surface.
One note to address part of his questions: these corrugated ends reflect the state of American fabrication economy -- first in the capability of rolling mills to produce sheet and perhaps rolled forms, and second in the ability of large hydraulic press capability and die making to go with that.
It makes sense to think about the kind of stresses in a car end and how they are tied into the rest of the car's structure. While the under frame and bolsters produce most of the loadbearing and longitudinal support, the only transverse members preventing rack of the body are the ends. That weird Pennsylvania end continuously transmits rack load without stress concentration, or at least I think that was the idea -- I suspect it was also an idea for using much thinner plate, perhaps a perceived wartime expedient. In railroad service this might not be a true economy, or even practical for very long with normal wear and tear in a railroad environment; it would be interesting to see the reasons the idea did not 'catch on'.
cv_acr 7j43k I think it's referred to as a non-terminating end. Don't know why. Kalmbach's freight car book says they showed up in the '70's. "Non-terminating" means the end doesn't terminate the sides... that is, you can see that the end corrugation is between the side sheets and corner posts. As opposed to early styles of terminating ends which are wrapped around and riveted or welded to the car's corner posts, like in the 40' GBW, CMO and WM example boxcars in the post above.
7j43k I think it's referred to as a non-terminating end. Don't know why. Kalmbach's freight car book says they showed up in the '70's.
I think it's referred to as a non-terminating end. Don't know why. Kalmbach's freight car book says they showed up in the '70's.
"Non-terminating" means the end doesn't terminate the sides... that is, you can see that the end corrugation is between the side sheets and corner posts.
As opposed to early styles of terminating ends which are wrapped around and riveted or welded to the car's corner posts, like in the 40' GBW, CMO and WM example boxcars in the post above.
I think the "non-terminating" means the corrugation goes fully side to side. In the other corrugation pattens the currugation terminates before it reaches the side of the car (the corrugation comes to a point or feathers out). In the non-terminating style the corrugation goes all the way to the side sheet.
NP2626My guess is it is in some museum’s back lot somewhere.
No need to guess. The link I provided with the photo above http://www.largescalecentral.com/forums/topic/12181/composite-boxcar-a-new-prototy shows the car was photographed at the Danbury (CT) Railway Museum.
Rob Spangler
The brake wheel on that old boxcar is also broken. Note how the shaft appears to be at a slight angle, and just visible behind the corner of the flatcar in front is the bracket where the shaft should connect to the rest of the brake linkage, however the shaft has fallen out of this and you can see the bottom end of it hanging down in mid air as well as some hanging chains near the bracket.
wp8thsub There were various corrugation patterns on house car end and door stampings. Corrugation makes for better strength than flat sheet.
There were various corrugation patterns on house car end and door stampings. Corrugation makes for better strength than flat sheet.
NP 2626 "Northern Pacific, really terrific"
Northern Pacific Railway Historical Association: http://www.nprha.org/
The above car from http://www.largescalecentral.com/forums/topic/12181/composite-boxcar-a-new-prototy has a wood carbody with metal ends. Cars like this date from the early 20th Century, and sometimes wood cars were rebuilt with steel ends, and of course all-steel cars used similar ends too. Steel ends resisted damage from shifting loads better than wood. Different suppliers offerred variations in stamping patterns.
THis car has a fairly early type of "dreadnaught" end http://lariverrailroads.com/freight_car/wm28271.jpg . This end design was stronger that the earlier corrugted types and became common by the 1930s. There were again several variations of stampings produced by different manufacturers.
Eventually the "improved" dreadnaught end was introduced, with still greater strength compared to the initial designs http://www.steamerafreightcars.com/gallery/boxauto/cmo37662main.html . These were common by the 1940s, and once again varied between suppliers.
Other manufacturers had different ideas, including the ends from Pullman Standard like this GBW car, which also has a distinctive Pullman door design http://www.greenbayroute.com/1963933.jpg .
The improved dreadnaught and Pullman ends remained common on new cars through the mid-1970s. Since then the "non-terminating" ends like those on the WP car above almost entirely replaced them on new cars http://www.rr-fallenflags.org/wp/wp38087agd.jpg .
angelob66602.) When did corrugated ends on boxcars started?
Here's an early "oddball" example circa 1912:
PRR Photo
I don't recall this design ever being offered in a model. This car seems to have an early "plug door" design, too.
Corrugations, as has been pointed out, adds strength while allowing a lighter weight sheet metal to be used. Less car weight=higher lading weight=more profit.
Many door manufacturers used their own styles of corrugations. A Youngstown door had the typical rounded corrugations. A Superior type had six or seven rectangular panels. There were many variations in between. Railroads and car builders had their own criteria for specifying what type of door usually geared to the type of lading the car was intended for. Then there's "plug" doors (or combinations of both) to allow for the thickness of insulation.
Good Luck, Ed
I suspect this is the corrugated end the OP is talking about:
But there's that "door question". I'm not seeing that.
Mr. OP. Perhaps you could expand on this?
Ed
1a. Dreadnought is a form of corrugated end.
1b. I don't understand the question. Corrugation or crimping improves strength.
2. Shortly after steel construction was introduced around the turn of the 20th Century. Many cars were built with some form of corrugation or crimping of some sort in the 'teens and later.
Tom
(slightly edited)
I have a few questions.
1a.) What's the difference between corrugated and dreadnaught ends on boxcars?
1b.) How come it's the same situation on doors itself?
2.) When did corrugated ends on boxcars started?
Amtrak America, 1971-Present.