Factorio Forums

I have found undocumented behaviour with burner inserters, and i was wondering if this intended, or simply not clear.



In the example from the picture, i have a burner inserter thats emptying a chest of ammo into a turret.
In the beginning it will prioritize Ammonution (first slot item).
If the inserter is out of energy, it will take a coal piece from the chest.

But somehow after taking the coal, it will now no longer prioritize the first item in the chest, and will only take out coal (which obviously doesnt fit in the turret, jamming the system).
Shouldn't it switch back to ammunition?

Swapping the location of the two items within the the chest, results in a working system, where ammunition is dispensed, and coal is taken on demand.
This raises another problem, because it serves ammunition first regardless of the order in the chest (what if for example i prefer to dispense coal first).

After some testing i found that the bug is hard to recreate, because somehow the insterter knows its feeding a turret, but sometimes it just forgets when taking in coal?
Perhaps that the build order is important.


Update:
I haven't been able to recreate the bug, im sure that at some point i've had it, but none of my later attempts to make a burner inserter hand out coal instead of ammo to its turrets have worked.

Bug nr 2:

When placing a burner inserter out on the map, it is somehow able to move for a insertion or four.

During this time the fuel bar is completely empty, while still able to move.
(Note: Reddit pointed at me that this might be intentional, as it makes it easy to feed it directly after being placed).


Do you think this behaviour is intended, and if not, how do you feel it should work.

LordSquirrel wrote: Tue Jul 09, 2019 8:55 pm Bug nr 2:

When placing a burner inserter out on the map, it is somehow able to move for a insertion or four.

During this time the fuel bar is completely empty, while still able to move.
(Note: Reddit pointed at me that this might be intentional, as it makes it easy to feed it directly after being placed).


Do you think this behaviour is intended, and if not, how do you feel it should work.

Yes, that's known and intended (it allows them to fuel themselves without manual intervention).

The first sounds like it should only happen on an almost full burner inserter with an inserter stack size greater than 1.

tehfreek wrote: Tue Jul 09, 2019 10:54 pm The first sounds like it should only happen on an almost full burner inserter with an inserter stack size greater than 1.

Yet in that case it shouldn't be reaching for coal.

Thanks for the re port however without a way to reproduce this there's nothing I can do. Inserters (burner ones) don't have any priority system for what they grab except "If I need energy, find fuel". There's no system for remembering what slot it was grabbing from in a chest.

I've seen it too.

This thing is actually not so hard to reproduce:

• Have a non-stack inserter bonus researched, so the default stack size for the burner inserters will be 2.
• Place a chest, a burner inserter and a turret next to each other, just like in the picture by the OP.
• Put a stack of bullets into the chest.
• Let the burner inserter spend its initial energy.
• Manually put all the bullets back into the chest.
• Ensure to have exactly 99 of the coal in your inventory. Take a stack of it into your hand.
• Ctrl+Click-and-Drag the coal, stuffing it into the chest (must be 1st) and the inserter (must be 2nd).

What happens: the inserter reaches for the chest and grabs 2 coals from there to refuel itself. But it's slow, so when it happens, there will already be 49 coals in its own fuel box. 1 coal will get into it, and 1 more will remain in the inserter hand.

It's probably also possible to simply overflow the burner inserter with no stack bonuses and 50 coals, but that I've failed to reproduce (quickly at least). The 49 case, however, I've managed to recreate on the first try. I have a save file if anyone's interested.

It's actually exactly the same effect that absolutely everyone sees with the trains and the stack inserters, when those hang some excess items over the rails. But for the burner inserters with a target that can't take fuel in, it's actually a deadlock they won't get out of automatically.

Some fix could be made. The simplest probably is to drop any excess fuel onto the ground. Or simply destroy it. I have no idea if it's worth it. It doesn't affect boilers, and outside of that AFAIK the burner inserters only get any use in special challenges. In the latter case, it simply adds to the challenge.

If that is the reproduction steps then I would move this to minor issues and say "just don't do that".

I did have the bug without those steps, but to be fair my problem only happened once and i still have no way of knowing why.

As far as im concerned i'll keep an eye out for it, but seeing it wasn't game breaking, you can close this thread until i find out more