tetters' Duff Challenge part duex

[doctorwayne]

Glad to hear that you've got the majority of the drilling done - that's probably the most tedious part of the build, especially when you're doing multiples.

I generally simplify the brake rigging by eliminating most of the piping and only model that which is apparent in a track-side view. Since Tichy supplies the wire, I often include some of the piping, but you really have to decide for yourself what is necessary and that which is less-so.
Here's the general arrangement for the K-type brake. It was introduced in 1906 and outlawed for interchange service in 1953:



...and a view of what's visible from trackside (if there's enough light):



Westinghouse's AB brake was introduced in 1933, and was required on all cars built or rebuilt after September 1 of that year. The CPR's cars would likely all have been built in the '20s, and I doubt that any would have been re-built, at least not to the extent considered to be a re-build for such purposes. (For a car to qualify as re-built, the main requirement was a change affecting the car's frame in a structural manner. So a car like yours could receive new ends, new sides, and a new roof, yet not be truly "re-built"). Here's a Tichy car with AB brakes:



Here's a trackside view of AB brakes. Note that this CNR car is a USRA-type car similar to yours, but represents one which has been re-built with steel sides. The formerly-external bracing now shows only at the side sills. I'm not sure if the CPR modified these cars in a similar manner, but most railroads which owned such cars did so:



If you're modelling 1953 or later, your car should have AB brakes, and if your era is post-1954, the Andrews-style trucks, as seen under the M-K-T car, would be illegal in interchange service. Instead, the car would be fitted with one of the many Bettendorf-style cast trucks, similar to those under the CNR car.
I'm uncertain of the exact date, but some time between 1935 and 1939, the second grabiron at the left end of the car's side was introduced, and these were added as cars underwent regular maintenance, such as re-weighing, re-packing or other minor repairs.

Of course, none of this prototype background info need have any more bearing on your modelling choices than you're willing to accept. I have been known to indulge in the occasional bout of rivet counting, but I never count another modeller's rivets.

EDIT: I did a little research on the CPR cars, and many, if not all of the 3,500 cars of this type were originally built with Burnett hoppers in the floors, to facilitate the unloading of bulk commodities, such as grain or coal. When not in use, there were fold-down covers, which made the floor of these cars like any other boxcar. In the 1930s, CP began to remove the hoppers and re-numbered those cars into the 234000-238999 series. At the same time those cars received AB brakes and Ajax "power" hand brakes, like the type shown below. The "power" referred to the gears within the brakewheel housing, which offered a mechanical advantage over the vertical-staff type.



Evidently, these cars were delivered new with sixty-ton archbar trucks, which were replaced, at the same time as the other changes were made, with cast sideframe trucks of ARA design.
There's some info on USRA cars of this type in the July 2004 issue of RMC.


Wayne