Factorio Forums

Just noticed something odd..

The loop in this belt locks up and stops moving.
This one doesn't. Seems normal so far...
This one does. Not sure why.
And this one doesn't just by adding a splitter?
Why would loop #3 stop moving? And why would adding a splitter that goes nowhere change anything?

As far as I understand belt mechanics:

The belt stalls, because there is no free position where an item could move to. A splitter has a tiny internal buffer that seems to provide this free space. The buffer is less than the space required for an item, so it never actually contains an item, but it seems to provide enough space for this.

The one belt that stalls even with a splitter is because items are tried to funnel from 2 inputs to 1 output, and if the splitter tried to take the item from the outer input it isn't able to output, because this would add one more item to the loop, for which isn't space available. In this case the splitter locks, not the belt loop.