A friend pointed to a photo and said "It can't be too early, it has
corrugated ends", after which I told him corrugated ends were much
earlier than he thought. The USRA box cars had corrugated ends in
the late teens and... I guess I don't have a clear impression beyond
that! When were the more common types introduced? I know that only
the very last X29's had corrugated ends, but I don't think that the
USRA cars introduced them, nor that the X29's were the last hurrah
for plate ends. I gotta admit, I find myself a bit puzzled about the
advantage of corrugated over plate; I guess it's to add strength when
a load shifts and clobbers the end due to braking or slack action. I
think they tried corrugated sides on some gons, right? The sides
still got all beat up... and I don't remember seeing a photo of a
plate end car with dents indicating a need for the strength of a
corrugated end... I don't remember any corrugated end photos with
end damage, either.
Dean Payne

Dean Payne wrote:

I gotta admit, I find myself a bit puzzled about the
advantage of corrugated over plate; I guess it's to add strength when
a load shifts and clobbers the end due to braking or slack action. I
think they tried corrugated sides on some gons, right? The sides
still got all beat up... and I don't remember seeing a photo of a
plate end car with dents indicating a need for the strength of a
corrugated end... I don't remember any corrugated end photos with
end damage, either.

It's primarily stiffness, not strength, Dean; the strength depends on the thickness of the steel sheet, while the stiffness depends on the geometry of its arrangement. Think corrugated cardboard, which is really only heavy paper.
Oh yes, corrugated steel ends sure did get bulged and dented from the inside. There are numerous photos out there.

Tony Thompson Editor, Signature Press, Berkeley, CA
2942 Linden Ave., Berkeley, CA 94705 www.signaturepress.com
(510) 540-6538; fax, (510) 540-1937; e-mail, thompson@...
Publishers of books on railroad history

Experimental pressed sheet steel corrugated ends were around before
1910. NYC's first experimental use was 1912 and their first
production application of them was 1914.

This might not be clear to non-engineers, but the idea is not
necessarily to increase "strength" as to increase resiliency, or
IOW, the ability of the end to absorb the energy of impact of the
load shifting against its inside. By absorbing energy, the impact
event is spread out over time (e.g., from 0.1 sec to 0.25 sec),
resulting in a lower peak stress on the rivets that attach the ends
to the sides, roof and end sill, increasing the threshold at which
the end would tear away from its attachment. Also reducing the peak
bending stress within the end sheet itself, thereby increasing the
threshold at which the end would become permanently distorted. It's
all about controlling a high-energy event to minimize peak
stresses. Introducing the corrugations did increase "strength" by
making the material stiffer in the horizontal direction, but it also
gave the end the ability to stetch elastically in the vertical
direction. That elastic stretching gives the ability to absorb the
energy of the impact.

I suppose the amount of damage to the lading would be slightly
reduced as well, but that was not the primary objective.

Hope this helps -

Jeff English
Troy, New York


--- In STMFC@..., "Dean Payne" <deanpayne@n...> wrote:

A friend pointed to a photo and said "It can't be too early, it

has

corrugated ends", after which I told him corrugated ends were much
earlier than he thought. The USRA box cars had corrugated ends in
the late teens and... I guess I don't have a clear impression

beyond

that! When were the more common types introduced? I know that

only

the very last X29's had corrugated ends, but I don't think that

the

USRA cars introduced them, nor that the X29's were the last hurrah
for plate ends. I gotta admit, I find myself a bit puzzled about

the

advantage of corrugated over plate; I guess it's to add strength

when

a load shifts and clobbers the end due to braking or slack

action. I

think they tried corrugated sides on some gons, right? The sides
still got all beat up... and I don't remember seeing a photo of a
plate end car with dents indicating a need for the strength of a
corrugated end... I don't remember any corrugated end photos with
end damage, either.
Dean Payne

I will add to the useful analyses provided by resident engineers Tony
Thompson and Jeff English that X29-style plate steel ends had internal
stiffeners in the form of vertical hat-shaped end posts (that's what those
rows of vertical rivets on the outsides of the ends were about) to which
internal wood linings were attached and which, up to a point, absorbed
impacts from shifting cargo.

Corrugated steel ends, as Jeff says, began to appear ca. 1910, first with
the corrugations stamped inward and later with the corrugations facing
outward (in the teens the Canadian Pacific built an experimental single
sheathed box car in which both the end and side sheathing was corrugated
steel). Prior to their development, wood ends were the most vulnerable
part of a box car, and damage to car ends from rough train handling causing
the cargo to shift was a chronic problem. Corrugated steel ends, though
they didn't entirely eliminate the problem, greatly reduced it, and after
corrugated ends were applied to all of the USRA box cars, relatively few
box and auto cars were built without them.

The Dreadnaught end, which first began to appear in the mid-1920s, was even
stiffer and more energy-abosrbent than corrugated ends (though not entirely
immune from damage), and was subsequently even further improved by
W-section corner posts (1940) and the postwar Improved Dreadnaught design
(1944). Other types of steel ends were developed (e.g. Vulcan vertical
corrugated and Hutchins in the 1920s, Buckeye and Deco in the early 1930s)
but were never widely adopted.

Richard H. Hendrickson
Ashland, Oregon 97520

Richard Hendrickson wrote:

Other types of steel ends were developed (e.g. Vulcan vertical

corrugated and Hutchins in the 1920s, Buckeye and Deco in the early
1930s) but were never widely adopted.<


I was looking at patents for freight car ends at the US Patent Office
web site some months ago and I noticed that there were literally
hundreds of patents granted for metal/corrugated freight car ends from
~1910 to ~1930. Some, I recall, predated 1910. There were multiple
patents for ends with "bulls-eye", "vertical corrugations", horizontal
corrugations, etc. Obviously very few ever became commercial products.
I never did find a patent for what Chris Barkan terms " the
indestructible end".

Bob Witt

To give credit where credit is due, I think I learned the term from Al
Westerfield. The "Indy" end was not corrugated of course, it was a particular
design of wood and steel framing and reinforcement.

The whole matter of building more robust ends had little if anything to do
with protecting lading. It was to reduce or eliminate the damage to the car
from shifted lading. It is ironically amusing that the RR's response to the
shifted load problems that generally inflicted severe damage on the customer's
lading, was to simply make the car more resistant to the damage.

Chris

--- In STMFC@..., Richard Hendrickson
<rhendrickson@o...> wrote:
(in the teens the Canadian Pacific built an experimental single

sheathed box car in which both the end and side sheathing was

corrugated

steel).

There was a shot of this car in one of the Mainline Modeler
issues covering the Dominion Box Cars. But the car was only included
as an interesting foot note, without any information given about
it's service life.
It would make an interesting addition to "the fleet", if it ran
at the right time. The corregations look like corregated roofing
material, so it probably could be modeled using Evergreen corregated
sheet, or similar.
Did this car actually go into general service, and until what
year?

Regards,
Phil Buchwald

I didn't mean to confuse people by implying the "INDY" end was a
corrugated steel end. That's the end I was searching for at the
patent site.

Bob Witt

CBarkan@a... wrote:

To give credit where credit is due, I think I learned the term from

Al Westerfield. The "Indy" end was not corrugated of course, it was a
particular design of wood and steel framing and reinforcement.<