Miners Not Filling Out Belt Fully

[Meehael]

Hey guys,

I wanted to test some min-maxing. I wanted to build the minimum quantity of miners needed for filling out a belt fully, so I went to an online factorio calculator and wanted to see how many electric miners do I need to fully fill out a blue belt (without any productivity bonues). Turns out, I need exactly 90 miners in total, 45 on each side. Ok, great.

So, I created an iron ore patch using the in-game editor and put 90 electric miners. Sure enough, in a minute, the belt was completely filled out, without any gaps (I hovered my mouse cursor over a belt and was checking for a minute to see if the number would drop from 8 to 7 or 6-that didn't happen).

Now, I did another test, and was surprised of the results. I researched 50% mining productivity and according to the calculator, this time it was enough to put only 60 miners exactly. Ok, I did that, however, after spinning them up for a minute, while testing, the belt continuosuly showed gaps. Every few seconds the number would drop from 8 to 7 or 6. I've also noticed the last 3-4 miners were quite often "blocked" with target full message.

I guess the productivity bonus and sudden drop of multiple ores makes a big difference in even distribution on the belt.

Did you guys notice this? Is there a way to approach this deterministically, while trying to min-max?

Thanks

[ovtchina]

I noticed the same thing when mining scrap with big mining drills, also with 50% productivity research.
Was trying to fill the express belt (45/s) with 6 miners, 3 on each side (7.5 /s each), and it didn't work - every time productivity bonus generated an extra item it always coinsided with a normal item being produced, with miner blinking a yellow light, indicating "output full" for a split second, even when outputting into an empty belt.

I was only able to solve it by outputting from a miner into a chest and using an inserter to output from a chest onto the belt - then everything works.

[Hurkyl]

FWIW, if you have four rows of 15 miners outputting onto two blue belts and then combine the two blue belts into one, you get the compressed belt you want.

If you insist on having one long belt, you might be able to do a similar trick by using an underground to skip past the last couple miners and start a new belt for the last few miners, and then use a splitter to combine them.

[jdrexler75]

It helps to have a small belt buffer (just one or two pieces) that sideloads into the output belt. This allows it to fill the gaps properly, whereas the miner won't always have an item ready when there's a gap, and there won't be a gap in time before the miner's output fills up.

You only need to do this for the last miner, or maybe two once your productivity gets very high.

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