In both the model and prototype world, passenger cars come with either narrow or full width diaphrams. Other than asthetics, is there any advantage the full width diaphrams offer? What factors entered into the choice of various roads as to which style to use? Were the two styles compatible? Thanks in advance for any info regarding this.
If I’m not mistaken, the full-width diaphragms were introduced with the early “streamliners”, partly to enhance their aerodynamic qualities and partly to give the train a more homogeneous appearance. I believe most roads replaced them with regular diaphragms in the '50s due to maintenance and/or compatibility issues. I couldn’t find much info on prototype diaphragms, though, so most of what I’ve written is conjecture. [:-^][swg]
I use the narrow ones from American Limited:
Wayne
Full width diaphragms were mostly put on the special type train sets and the named streamlined limiteds. Narrow diaphragms go back to the heavy weight car era with the rounded corners and clerestory roofs. No they were not compatible. Most of the streamliners lost their full width units early and were either never replaced or were converted to narrow ones. The Pennsy T1 locos had diaphragms between cab and tender when built and a couple years later they were gone. Here is one in with remnants of it.
http://www.northeast.railfan.net/images/prr5527.jpg
At least it lasted longer then the sheet metal over the running gear.
Pete
http://s1127.photobucket.com/user/erikclindgren/media/expo4.jpg.html
http://s1127.photobucket.com/user/erikclindgren/media/expo5.jpg.html
Ed
Nice pictures. Both the models and the prototypes.