This is an automated archive made by the Lemmit Bot.

The original was posted on /r/factorio by /u/AnauNaga on 2024-10-16 04:23:10+00:00.

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(I fixed the images here)

This game is pretty old, so I hope the information here might be new, or at least new to some people.

First off, what is this post even about?

Here I'm trying to answer the question of the fastest way to move items off a belt using a single stack inserter.

Some people already use some pretty well known techniques, but I'm going to cover some odd situations that can actually more more items than those techniques. I'm sure there may be other methods that work better, but this is what I've found.

tldr is at the bottom.

Basic concepts:

1. upm stands for units per minute. (Normally its ups, units per second, but I can't be bothered doing the math for a few dozen experiments)
2. items move on belts at the same speed regardless of turns. This can be a bit counter-intuitive because if we think of the belt as a quarter of a spinning disk, you would think that the outside of the disk needs to move faster than the inside to maintain the same angular speed.
3. inserters prioritize items on the closer side of a perpindicular belt and left side of any other scenario for a belt (thats left side of the forward facing direction of the belt)
4. inserters cannot pick up items from the input of a splitter. here's what I mean:

Also, i'm going to try and not bloat this post with too many explanations, because I'm not confident in the ones I have, and I think people care more about what works best rather than how a certain case works best.

Getting that out of the way, lets start with the numbers for basic situations:

Experiment group 1:

Experiment 1: 711 upm

Experiment 2: 977 upm

Experiment 3: 812 upm

Experiment 4: 773 upm

Experiment 5: 917 upm

Experiment 6: 881 upm

Experiment 7: 881 upm

Experiment 5 is an interesting case because the inserter is picking items off the outside edge of the belt and doing better than its symmetrical counterpart while experiment 2 is picking items off the inside of the belt and doing better than it's symmetrical counterpart

Now lets do some more interesting setups:

Experiment group 2:

Experiment 8: 812 upm

Experiment 9: 977 upm

Experiment 10: 812 upm

Experiment 11: 879 upm

Experiment 12: 879 upm

Experiment 13: 812 upm

Experiment 14: 1021upm

Experiment 15: 932 upm

Experiment 16: 932 upm

Experiment 17: 1021 upm

Now we have something interesting. This is our first count past 1k upm. Now, the setup I have for the Experiments that got past 1k is a bit silly. You see, since inserters prioritize grabbing the left side of a belt, I did a couple experiments with that, and I ended up doing Experiment 14-17 using only one side of the belt. Even though they still beat our previous record, they are still a bit silly.

I say its silly, because lets look at what happens if both sides of the belt are full:

Experiment group 3:

Experiment 18: 1156 upm

Experiment 19: 1156 upm (The image is wrong, it should've said 1156 upm like the left side)

So clearly, this scenario is less silly and more efficient.

Here are some other experiments I did that didn't perform as our best picks:

Experiment group 4:

Experiment 20: 800 upm

Experiment 21: 800 upm

Experiment 22: 775 upm

Experiment 23: 775 upma

Experiment 24: 773 upm

Experiment 25: 917 upm

Experiment 26: 800 upm

Experiment 27: 788 upm

Experiment 28: 800 upm

Experiment 29: 1156 upm

Experiment 30: 1156 upm

Experiment 31: 881 upm

Experiment 32: 881 upm

It should be noted that Experiment 29 and 30 are basically the same setup as Experiment 18 and 19.

edit: someone made a good point that I didn't include certain splitter experiments, so

here they are:

Experiment group 5:

Experiment 33: 699 upm

Experiment 34: 739 upm (each)

Experiment 35: 797 upm (each)

Experiment 1: 699 upm (this is a copy)

Experiment 36: 1008 upm

Experiment 37: 797 upm

I'm glad I added this, because experiment 36 gives interesting results. I believe its because the second belt acts as a buffer that can fill the output faster than 1 belt can. This is the same idea as how 2 green belts can fill a red belt faster than a single belt can fill a red belt.

Now, we have our best options, but could we use them to fast load items into a train?

Well, 1156 upm is 19.27 ups (units per second), so theoretically a stack inserter (maxed out 12 items per grab) can handle a single green belt which is 15 ups or 900 upm.

The splitter on the left just tells us if the belt is getting backed up, which it clearly is

Also, I'm not using an actual train car, just 6 inserters in a line to simulate a loading spot.

Well, in this case it can't handle 6 green belts, but I think thats because of the speed at which green belts can move items in front of the inserter.

So what if we have the green belts put items onto a red belt? we could make assumptions that it doesn't work, but lets find out anyways.

So it works! The splitter on the left isn't releasing items, but you can also see that none of the red belts are backing up either. I said I wouldn't do explanations, but I'm pretty confident on this one.

Basically the red belts can move the items fast enough off the yellow belts that gaps form between each item.

This means that a sort of buffer can be made on the red belt for the inserter. Also notice how the belt on the bottom is still yellow. The speed of the bottom belt doesn't matter so much.

We can take this a step further. if 1 stack inserter can handle 19.67 ups, then 5 inserters can handle 98.35 ups. Thats over 2 blue belts of items. In contrast, if we used the curved belt method then 5 inserters could handle 76.42 ups which is just not enough. Lets confirm it works!

Okay, this time I ran into a few issues, but I got it to work. First, the belts on the bottom MUST be green belts. I have no idea why, but also this is the only splitter setup I could get to work. I tried 2-5 balaners, lane balancers, advanced lane balancers, and a combination of everything. Honestly its probably too much effort to the point that it makes more sense to just use another inserter. like such:

TLDR:

This is the most efficient way for a stack inserter to move items off a belt (afaik)

It moves 19.67 items a second