Re: Randy
Quote:
I'm interested in hearing more regarding Rob's criticisms. It would be really interesting if someone could compare a situation as it would be handled by JMRI Ops vs. how it would be handled by Car Cards or another system and point out the shortcomings of JMRI.
I'll try to make this coherent, but who knows how short I'll fall.
Let's assume we're running a yard with car cards. Every time a car shows up, you put the card with the others and automatically have a record of what's in the track. If it makes sense to move the cars to another track to keep the yard fluid, no problem, just move the paperwork. If you need to build a train at a particular point in the schedule, you grab the cars available for the required blocks. Assuming you've done your job blocking them, they should all be in the right order and can be pulled all at once.
JMRI complicates all of the above. First, unless you manually record every car showing up, you won't have a current inventory of each track in standing order unless somebody manually updates JMRI to record arrivals. The reverse is true of every car removed from a track. When I operate on a JMRI layout, I use the printouts to keep a hand-written switchlist of which cars are where and where they're going so I have current information at all times.
Second, given JMRI's insistence on sending cars into particular yard tracks, flexibility in shuffling blocks is greatly reduced. JMRI will assume a particular block is supposed to be on a given track, and it instantly instills confusion for everybody if you move it, even if doing so would otherwise make sense due to traffic patterns and track capacities. There isn't an easy way to propagate all that through the system and get everybody informed about the current status of the yard, but I suppose an alert yardmaster could handle it. Since the existing printouts in the hands of the train crews would still show the old track assignments potential for confusion is increased.
Third, every time I see JMRI address a block to be picked up from a yard, invariably the cars to be picked up are not adjacent, and the yard must then cherry pick say 4 cars from a track of 10 to put in train XYZ. JMRI doesn't maintain cars on a given track in standing order, and I've never figured out how to block everything so I can just pull say the first 4 cars and have them be the right ones. There's always something to cherry pick instead of just pulling x number of cars from a block.
In the same vein, JMRI does not readily adapt to pulling cars from given blocks at a particular call time. It doesn't "know" when cars get into a track unless manually updated, so you can't just say that train ABC pulls all cars for destination 1 and fills to 20 cars with destination 2 at 10:30 AM. It's set up anticipating that certain cars will be in the track, and forces you to pull by car number instead of destination. If the anticipated cars aren't there due to delays in other trains or switch jobs, it creates a cascading impact on every destination down the line where the specific cars are expected.
In short, JMRI requires a lot of clerk work to be done during the session to keep records current, something car cards or a manual switchlist will do automatically.
