Part 3

In the previous blog posting, I had managed to get JMRI to route 10 cars between Cassette and Bakery. This was good but two things bothered me:

1. The same cars were always routed to Bakery. For example, since there Is only one grain hopper it was shuttled back and forth between Cassette and Bakery. I would like to mix that up a bit.
2. The cars moving into and out of the spur are the same block of 5 each time.

So, the first thing I will do is add some more cars into the mix at Cassette. To keep things simple, I will just add another grain hopper for now…

… and I run the Bakery Turn train.

The red grain hopper is picked up and sent to Bakery. So, I run the train a few more times.

Wait! I have two grain hoppers being sent to Bakery but Bakery only has one spot for grain hoppers. How am I going to enforce the spot types on the spur?

Maybe I need to model each spot type as a separate spur. So I set it up at the Bakery location.

There are a couple of things to note about this entry.

The name is “Bakery-1-HO-Grain”. The “HO-Grain” is so that I know that this spur is supposed to handle grain hoppers only.

Remember that JMRI will ignore all text preceded by a hyphen and a number (including the hyphen and the number). So, for all the reports and manifests, this spur will be known as “Bakery”.

The length is a big longer than the length of the cars expected. JMRI adds a bit to the car length when calculating so making this a bit bigger helps. If it is too small, the Train Build Report will tell me about that.

I have indicated that this spur will only accept HopGrain cars.

I will add spurs for the tank and box cars in a similar fashion.

I named the box car (XM) spur without a specific goods suffix since I want many things to arrive and depart in boxcars.

Time to run the train again but, first, make sure that any cars that were on the old Bakery spur are relocated to new spurs and that the loads are correct.

This is the train manifest after the first train.

The red grain hopper is picked up from Bakery and dropped at Cassette, so Cassette has two loaded grain hoppers.

On the second build, the red grain hopper is picked up and sent back to Bakery. This is good because even though Cassette had two loaded grain hoppers, it only selected on to ship.

On the third build, the red grain hopper is picked up at Bakery and returned to Cassette.

The red grain hopper is cycled between Cassette and Bakery and the blue grain hopper stays at Cassette.

Time to look at the Train Build Report again!

So, JMRI found both grain hoppers in Cassette and then found a spur at Bakery for the red grain hopper. When it came time for the blue grain hopper, the spur at Bakery was already full.

This is an important discovery. JMRI processes the cars in the order they are found when the cars are located on a spur.

I’ll look at ways to have both grain hoppers show up at Bakery in my next blog post.

Do not try to put schedules in to start

What do you suggest?

Art:

What would you recommend to get the behavior I want? That is, to have the red and blue grain hoppers show up at Bakery? I have some ideas but nothing speaks like experience which you seem to have.

Why the avoidance of schedules and custom loads? What prompted you to recommend against them?

-david-

Thanks

Thanks for doing these tutorials.  They are very helpful.  Now that I am developing an operating scheme for my layout, I've found a renewed interest in it again.  Already looking forward to Part 4.

Could you try and reset

Could you try and reset cassette as a interchange instead of a siding? As I understand JMRI is trying to move loads between destinations and gives priorities to sidings. Perhaps this could work and would be also quite simple to try.

Regards

Daniel

Back to an interchange

Daniel

The reason an interchange won't work is that interchanges will not toggle the load state of a car.

I have something that works but I want to refine it before I post part 4.As you can see, things are starting to get a bit trickier, so I need to make sure that my postings are clear.

-david-

It's good to know

Shane

I am happy that you are finding these postings helpful. It is interesting to me just how much operations action a simple siding can produce. If I am lucky, I should be able to post part 4 this weekend.

-david-

Dave, you have already shared

Dave, you have already shared what is truly a small fortune of information for using this program. For that, Thank you!  I had an idea - these logic problems are fun!

Perhaps you can solve this in the same way you solved the siding length.  You need a place where more cars can be set, and you need a length of track where the load state can be toggled.  Make Sidings within Cassette where the loads can be toggled, and then allow for the cassette itself - or the point on the track right before the track - to be called " Cassette Interchange"

The one thing...

I've noticed so far is that presently at this stage in the tutorial the same cars on my own layout are being sent back and forth with little variation.  As Dave mentions in his last post, cars are sorted in the order that JMRI finds them.  I feeling I know what needs to be done next to solve this situation and I may try something in the meantime, but I am curious to see if I am right about it.  I've seen that little check box that goes something like, "First in last out" and I wonder if that might have anything to do with it?

I think it may be that

I think it may be that JMRI is choosing the car with the least moves.  Once the red and blue cars have similar total moves might it pick them more evenly? 

This is a great tutorial.  I've set up and played with JMRI and really enjoy it.  I haven't gotten much beyond about where you are right now, so the next entries will be of great interest to me.  

Least Moves

RSeiler

I tested this out by resetting the move counts to zero for all cars and then building trains. It looks like you are correct, the car with the least moves is selected.

This is the great thing about doing a worked example. People see things that I don't and, together, we all learn new stuff.

-david-