in the real world isn't a box car a box car? I've been reading a lot about how to operate your model rr --- it seems we overdo it a bit, yes? I mean some methods keep track of a specific car.. but in the real world, when shipper A needs to ship goods A and needs a box car to do it, any box car that is empty will do, correct? or do they pull a specific box car for that shipper? thanks
I'm not clear enough on the specific rules to give an authoritative answer. But, RR-X has to pay RR-Y a daily fee for each day a RR Y-lettered car is on RR-X's tracks. Plus there's some FRA rules that say a car has to be returned to its "home road" along the same route as its "outbound trip". Plus, an empty car generates no revenue. So RR-X will preferentially choose a boxcar that according to the rules needs to head the general direction of the shipper's shipment, plus what will get that (foreign) car off its tracks (and off its books) the quickest. From the shipper's perspective, unless they own or lease their own cars, any boxcar of the required sub-type is the same. But from the RR's perspective some are more "equal" than others (see above). Cars in "captured service" or privately owned leased cars are handled differently. For instance, it's not unusual for an entire unit train to (almost) never be uncoupled, and to run endlessly from loader to unloader and back, barring required repairs on the cars. I'm sure someone who understands this better will be along shortly to clean up my errors and omissions.
No. They cannot just grab any car. Someone else might be waiting for it. Things have changed over the years. It used to be that to protect some good customers, a local agent would even quietly stash a few cars.
The per diem box car era was an attempt to address the flow of cars. It would depend upon the era he is modeling. However, you still could not just freely grab a car, as it might have already been en route to a shipper for loading. PD cars came about in 1974, when the various "_BOX" cars such as RBOX were initially built A freight car had to be released within a certain time, back to that owner, or the shipper ended up paying (demurrage) an extra charge for delaying next use of the car. That car should have then been returned to the owner, which transit time delayed it's next use. Meaning it was making no money. A per diem car did not need to go back "home" for assignment. It could immediately be routed from last unloading point, to next use. In theory this helped make cars more available and earning more money. But had someone simply grabbed it for use, which did now and then happen, the unhappy assigned shipper who was left sitting and waiting would scream and shout....
