Long distance shipping decisions

[AngledLuffa]

After my most recent stone outpost ran out, the next desirable stone location was train distance rather than easy belt distance. I duly set up some miners and furnaces and started shipping everything produced. Now I have dozens of supply chests full of brick I'll never use (*). How to best limit the train shipments to only ship what I need?

A circuit at the source to disable the source if the destination logistic system already has enough would be ideal, but would require an enormous amount of colored wire.

A circuit at the destination to disable the station would require different destinations for brick and stone, not to mention they would need to be separate from all the other intakes. It would also have some poor interactions with possibly having multiple stone sources in the future.

A circuit at the destination to disable the inserters which unload the train would either require different destinations, or it would require the stone train to aimlessly go back and forth when no stone is needed.

I don't think it's possible to use the circuit system to set the destination of a train, although that would be a pretty good solution for this issue.

* - I've already set up purple bottles at a separate "offshore" facility, removing the most obvious solution for having stupid amounts of brick.

[eradicator]

A circuit at the source to disable the source if the destination logistic system already has enough would be ideal, but would require an enormous amount of colored wire.

Circuit wire comes free with every blueprint.
Other than that...is having more stone buffered than you currently need breaking anything for you? I don't see any inherit problem with having full buffers at the loading station. If it bothers you a lot just...limit the buffer chests slots? (Without knowing specifics about your base layout it's hard to give better advice based on the rather vague description in the OP).

[AngledLuffa]

The home base, where the rockets are built, has used the following pattern for a long time. Trains from remote outposts dump all of their cargo into active provider chests, and the cargo then gets sent via bot into storage chests (no filters). The logistic system then routes those goods to where they need to go.

Even when production for some goods is more than normal and the storage chests start filling up with those goods, it generally isn't a problem as I eventually add another rocket and the slack gets exhausted.

The problem here is the slack goods, raw stone and brick, will never get used up and will eventually completely overrun the storage chests.

I can see how sending a green wire all the way to the remote outpost would be possible, but is it the best solution?

[quyxkh]

Simplest would be to set the bars on your chests so they don't buffer too much.

[Termak]

Stop making brick if you have enough, limit stone to whatever amount you want to buffer. Problem solved, right ?

[Zanthra]

Setup a holding station as a siding before your main station, then tell the station to send the circuit conditions to the train. Add the siding as a stop into the train that goes to the brick outpost, and then tell it to depart the holding station only if the circuit conditions indicate stone or brick levels are low. Would be best if you have separate trains carrying stone and brick with separate holding stations, or you just smelted the stone to brick at base.

If you need to you can have the holding station departure condition wait for a piece of stone or brick to be loaded onto the train to be carried as an indicator of which item it needs to bring back.

[eradicator]

Zantras intermediate stop solution sounds like a good compromise to running a wire to every outpost. An alternative would be to not use active provider chests, but passive chests. Yes, that would mean you have to provide one extra station that would be blocked by the waiting stone train most of the time. But it would also mean that you always have a minimum buffer of stone/bricks available in the network without any additional signaling.
More generally speaking you have simply reached the usability limit of all-purpose active provider based main stations, and you're going to have to specialize from here.
If you want to go mad on circuits you could also try signaling the unloading filter-inserters to not unload based on the current logistic stock. But that would mean the stone train goes back and forth between loading/unloading stations without it's content actually changing far more often than required.

[AngledLuffa]

I agree that Zanthra's parking lot solution is the best. The best part about that solution is it is easily extensible. If I add more trains with the same resource I don't have an unlimited need for (something other than brick, probably) the parking lot can just be larger to accommodate the extra trains.

It also scratches all the really desirable properties:

- wires don't go everywhere
- don't flood the network with tons of unwanted goods
- trains don't go back and forth without doing anything ad nauseum

Thanks!

[Impatient]

Imo the best solution in general is to process everything at your base. Just raw materials - stone in your case - are shipped around. At the base the stone then is funneled to where it is needed (eg rails, bricks, ...).

At the base a player usually sets up an unloading station for every resource needed (iron ore, copper ore, coal, stone, uranium, crude oil) and tracks where trains can wait for unloading. The uranium unloading station as a special case usually unloading uranium and loading acid into a tanker of the same train. The waiting trains then also serve as a buffer.

This is the most common solution around by far.

[Engimage]

The most simple solution to limit inbound shipping is limiting the unloading station chests to desired value and setting up a train leave condition to Empty cargo. No circuit wires.
This will effectively stop the train from moving until all resources it brought in will be consumed.
The same limitation should be on loading station - you should not buffer full chests of stuff there. Limit it to 5 slots (if 2 sides of chests) or 10 (single side) per chest and you are good.