Diaphragms

Model Railroader General Discussion (Model Railroader)
1

I am starting to think about putting more correct diaphragms on all of my passenger cars. I have done some research, but can not seem to find which roads and eras of passenger cars had full width diaphragms and wich preferred regular ones. I know the heavy weight cars, but wich of my smoothside and which of my streamlined cars had full width. Can anyone help me.
Thanks

2

What passenger trains are you modeling? Here is a great link to research prototypes…

http://www.trainweb.org/passengercars/

Several roads such as Southern Pacific and New York Central used full width diaphrams.

The American Limited diphragms are great, but these things look awesome…

http://hitechdetails.com/

I have yet to try them out, but I am about to model a '50s era Sunset Limited, and I am going to use them. I will probably go broke doing so, but what the heck.

3

As a rule of thumb, ltwt cars built before WWII were built w/ full width diaphragms and post-WWII cars were built w/ the narrow ones and as the earlier cars were shopped they were converted to the narrow type. One notable exception to this was the original (1947) ltwt Empire Builder (there were probably others as well) but by the 1950 version they were narrow. The SP started converting to narrow after WWII but many of the articulated car sets retained the full width diaphragms at the articulated joint after the ones at the other end had been converted, probably due to the dificulty in separating the cars to get at them.

4

I definately would not use that as a rule of thumb. That may serve true for the SP, but not all roads. For example, Santa Fe seemed to stray away from the full width diaphragms altogether.

Edit: almost all of the passenger trains with fixed consists, such as the Green Diamond, the Tin Worm, and Zephyrs were built with full width diaphragms. Most of those were pre WWII, and would account for that. The best thing you can do is to research your prototype and go from there.

5

The 1946 Pere Marquettes had full width diaphrams (except the square end observation cars). However, several of the original cars were sold and replaced with cars from the C&O’s 1950 Pullman order. I believe those had narrow diaphrams.