Re: 1937 AAR boxcars: Dreadnaught corner posts

Eric Lombard

Hello Everyone,
Follows some information about the transition from square corner to rounded corner Dreadnaught ends starting 1939. This information was extracted from my box car database. I believe at this stage of development  (35 years) that that data is pretty solid. However, in common with all lists, spreadsheets, etc, compiled by our fraternity it is a work in progress. In furtherment of that aim I put this information out in hopes someone might correct or add to it.
On the advantages of the W corner post:
"...corners have been rounded to a generous radius and W-section corner posts applied, this combination functioning to produce action to prevent the sides of the car pulling in under a heavy impact. By actual test at the University of Illinois, this end is 25 per cent stronger than the old conventional type without the round corners and the W-section corner post." Standard Railway Equipment Manufacturing Co. advertisement in 1940 Car Builders' Cyclopedia of American Practice (15th Edition).
It would be interesting to know about the development and testing prior to the recommendation by the AAR, apparently at the University of Illinois.
4-1939  Recommended use of W corner post by AAR
Follows is a list of all series initiated in 1939 built with W corner posts. The all-welded and singular GABX car has rounded corners but there is no information on whether it had W corner posts. Paste it up as a puzzle. 

The first application in production developed jointly by UP and Standard Railway Equipment Co. 1939[6]-1939[11] , 1200  BLT:
**1939[6]-1939[8] and 1939[10]-1939[11] 187000-187499, Omaha, NB.
**1939[6]-1939[11] 187500-188199, Grand Island, NB.
Marks Serial Qty Builder Date
GABX 1940 1 GAT 11-1938
O-WR&N 188300-188999 700 UP 6-1939 10-1939
UP 187000-188199 1200 UP 6-1939 11-1939
M-I 4000-4249 250 MTV 7-1939 8-1939
UP 9100-9199 100 UP 8-1939 10-1939
CTH&SE 19039 1 MILW 9-1939
D&RGW 68000-68399 400 PSC 9-1939 10-1939
MILW 19000-19082 82 MILW 9-1939
LAPX 101 1 PSCx-1939
MILW 18000-18999 1000 MILW 10-1939 3-1940
NYC 62000-62299 300 DSI 10-1939 x-1940
NYC 91000-91199 200 DSI 10-1939
D&RGW 65100-65199 100 PSC 1-1939 12-1939
LAPX 102-121 20 PSC 11-1939 12-1939
WM 27501-28000 500 PSC 11-1939 12-1939
NYC 176000-176199 200 DSI x-1939 x-1940
MILW 19083-19187 105 MILW 12-1939 1-1940
PRR 65400-66399 1000 PRR 12-1939 2-1940
Square corner Dreadnaught ends continue to be built after 5-1939: 35 series totaling 8416 cars by the end of 2-1942. Soo Line, especially, seemed to be partial to them or maybe got a price break? Nine of the last 11 series with square corners, 1600 cars built 7-1940 to 2-1942, were for Soo. To provide perspective, 70,220 cars with W corner posts in 188 series were initiated 1-1940 to 2 1942. The transition was indeed rather fast.
I welcome any comments, thoughts or data!
Eric Lombard
Homewood, IL

Join to automatically receive all group messages.