inserter pulling fuel from a burner miner before it burns?

[sparr]

I know that inserters pull fuel from miners.

My problem/question is about timing. If I have one burner miner sticking fuel into another burner miner while an inserter waits to pull fuel out of that second miner, why does it get grabbed before it gets burned?

[BlakeMW]

This can happen due to the order the game processes things on each tick.

The setup you describe should work if you place the burner drill being pulled from after placing the burner drill feeding it. The drills are processed each tick in order of placement, this means the feeder drill will feed a coal into the pulled-from drill, next the pulled-from drill is processed and it immediately consumes the coal. If the drills are placed in the opposite order it is only in the next tick that the pulled-from drill gets a chance to consume the coal - that is what gives the inserter an opportunity to remove it before the drill can consume it. Hopefully that makes sense.

[sparr]

That's good to know, and unfortunate for my plans. If I'm going to place miners in a loop, one of them will have to be placed out of order

[BlakeMW]

I think you should be able to arrange for a burner inserter to feed the out-of-order burner drill - one inserter pulling out, one putting in.