Factorio Forums

When a fast inserter tries to pull from an express underground belt but the belt feeding into the underground belt is a fast transport belt or a transport belt the timing of the transition between the speeds of the belts causes the items to speed up and the fast inserter is stuck in a loop of trying to grab the item, and then resetting to its default position, then trying to grab it again.

Strangely the only way for a fast inserter to pull from an express underground belt is if the belt feeding into it is also an express belt. This is only true for one direction as well. If you try to pull in the same direction as the belt, it doesn't work, but if you try to pull the opposite direction it does.

Question - Why does the inserter reset its position when it should know that it needs an item from the belt? Shouldn't it just wait in an extended position for the next item on the line? Is there some other strange bug happening here?

I have never noticed this particular problem before but now that I have a build that requires me to do something like that its quite annoying that I need 1 extra space for an express belt on one side of the build for it to function properly.

This is not a bug, the window for pick-up on underground belts is very narrow and inserter can get stuck chasing items on it in general.

What I'm saying is that its inconsistent behavior, because in every other case, the insert will pick up the item. Only when you are using an underground express belt connected to a belt that is not an express belt in only 1 direction does the inserter not work. I would expect it to be the same whether the inserter is picking up items coming towards it or going away from it but instead its biased towards one direction and only when another belt is causing the items to transition between belt speeds.
This is a problem with the animations being sychronized to the offset of the item and getting stuck in a loop. This would be avoided if inserters simply did not reset their position when they know the space behind them is requesting an item.

Loewchen wrote: ↑Sun Jun 02, 2019 9:35 am This is not a bug, the window for pick-up on underground belts is very narrow and inserter can get stuck chasing items on it in general.

Not sure if I was clear enough or you didn't really read my post carefully enough.
This is not an issue of too fast for the inserter to keep up because thats not true, it can ONLY pick it up when its fast. Thats very strange. The item speeds are the same no matter which direction the belt is going, so why can it only pick it up in one direction with a faster belt?