Re: Manufacturers Railway Mather box


Dennis Storzek
 

On Wed, May 1, 2019 at 12:25 PM, James SANDIFER wrote:
Interesting is the model car height data. Several of the models have one of the heights as 5-0, 5-2, 5-5 and 5-8. The only dimension that fits those numbers is the height from rail to extreme width. Was this a common practice in dimensional data or did Proto mess up? Dimensional Data has always been awkward for me to understand, and It seems that railroads did not measure the cars the same way.
The total height of cars has never been particularly important to North American railroads, given our large clearance diagram. The mainlines were laid out so that there was clearance for a man standing on top of the car, and low obstructions just ate into that extra 6', marked by telltales to warn the men to get down.

The clearance point that was problematic was at the eaves, where tall cars were likely to interfere with arched openings and canopy braces. When the ARA standardized dimensional data in 1926, all they concerned themselves with was the interior dimensions (which were important to the shipper) and the width of the eves, designated as EW, and the height of that point above the rail, designated as EH. As I understand it, this was to be measured at the highest point along the eaves, which would be the edge of the latitudinal walk.

This was revised in the early thirties to add the extreme width information. The eave dimensions were moved to one line, as EW  00-00  H  00-00, and the new extreme width was added as a line above, EXW  00-00  H  00-00, the H being the height of the extreme width above the rail. If it is close to the eave height it is typically the door hangers; if around 5' it is the door handle or seal staple.

Dennis Storzek

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