Factorio Forums

I have a main bus consisting of multiple lanes of e.g. iron plates. Every now and then I split of some from the bottom most lane for use. So that eventually gets empty while the other lanes have all the iron plates. So they need to be balanced. At some point I have used up half of the 4 lanes and after balancing now every lane carries 50%. That means a simple split of the bottom most lane will only get 25% throughput while there is still 2 full belts full of iron plates on the bus.

I know I could merge lanes and use only 3, 2, 1 lanes as good are used up but usage varries a lot so where to merge constantly changes.

So I am looking for a belt unbalancer. Lets make a concrete example: Lets say we have a 4 belt bus going left to right. I want something that puts all the goods on that fit on the bottom most lane, every left over on the bottom middle lane, whats left on the top middle lane and if anything is left on the top lane. The design should have full 4 lane throughput.

Best I have is to split each lane 2, 4 or 8 ways and merge all but one lane into the next lower lane with that lane having priority. But that leaves 50%, 25% or 12.5% on the top lanes. Am I wrong that getting the top lane empty if not needed requires ciruits?

The best unbalancer is a 2-belt to 1-belt splitter. When a belt runs out of resources, merge it with the belt above.

That does not fullfill the requirement to have 2 belts throughput if needed.

If it's just 2 lanes, the process is very simple ... split from one lane, then put a splitter on both lanes to rebalance the remaining output.

If you want a 4 lane split, that's a different matter... try this.

There's a stickied thread at the top of this subforum talking about priority splitters:

viewtopic.php?f=202&t=32817

From what I understand of the OP's needs, this should do the trick.

Azraelle wrote:There's a stickied thread at the top of this subforum talking about priority splitters:

viewtopic.php?f=202&t=32817

From what I understand of the OP's needs, this should do the trick.

If OP wants a circuit-free solution (as this forum board is about) then that won't do the trick. If a solution involving circuits is okay then the thread you linked to partially works. When the two input belts are only nearly saturated then items will leak through to the overflow output before the prioritized output is fully saturated. This design, albeit having a larger footprint, handles overflow splitting better.

I take branches from different bus lines and combine some of the bus lines after some high consumption production cells. For example green circuits to blue circuit production.
http://imgur.com/a/gqSJQ

If I need maximum belt capacity I take half from two belts and combine them with the splitter. Then I get full belt if bus lines are full, but can keep full bus throughput in the situations when consumption is less.
http://imgur.com/a/bNZpD

I do not understand why so many keeps for example 4 belt buses through their factories because most of the stuff is consumed in certain production units. For example my base uses about half of the iron plates to produce steel and most of the remaining goes into the green circuit manufacturing. If I have total iron production of 4 blue belts, 1 red (or maybe even yellow) belt is enough after steel and green circuits production cells. The most of copper plates are used for the green circuits and low density structures. And so on. I try to put these high volume production units at the beginning of the bus so that bus area is freed for higher variety of more refined intermediate products. Therefore I can build aesthetic (this is IMO of course), practical and relatively compact factories with 2 (or 3) buses, straight unobstructed concrete walkways and rectangular production cells.

Hannu wrote: I do not understand why so many keeps for example 4 belt buses

Well, a belt can be used as storage. More belt, more storage. But in general you're right.

Innomin8 wrote:If it's just 2 lanes, the process is very simple ... split from one lane, then put a splitter on both lanes to rebalance the remaining output.

If you want a 4 lane split, that's a different matter... try this.

That leaves both belts balanced, not unbalanced as I asked.

.oO(I'm thinking many don't read the "circuit-free" part of this forum.)

I have an idea how to solve this that needs some space. But haven't build it yet so no screenshot or blueprint. But here's the idea:

Say you have a bus with 2 belts A and B. You use a number of inserters to move items from belt A to temp belts T1 and T2 on either side. Then you tunnel the T1 under belt A and belt B and merge them into belt B from the side. Use enough inserters for the full throughput and belt B should be filled nearly to the max with only overflow remaining on belt A.

I noticed though that sometimes belts have little gaps between items where an item doesn't fit. But if put one faster belt in they get compressed and the gaps get combined to fit an item again. So that's something to do here too for perfectly filling belt B.

You could use splitters to 'force feed' a selected line.

With three lines in parallel (and not adjacent), have a splitter in the top and bottom lines, with the second exit turning towards the middle lane and feeding into it.

N35t0r wrote:You could use splitters to 'force feed' a selected line.

With three lines in parallel (and not adjacent), have a splitter in the top and bottom lines, with the second exit turning towards the middle lane and feeding into it.

That at most feeds half the contents of the outer belt to the middle one. Do it twice and you get 3/4. Do it trice ... you get the picture. But you never get 100%.

Here is my design for this with just 2 lines:
The top line is split to take half off. Then split again to feed the lower line from left and right. This design feeds into the tunnel exit so half the belt is blocked. Add one more length to feed into the belt instead of the tunnel exit.

You can do it by splitting off from all four lanes into a one-sided full-density branch line, instead of from one of the bus lines into a double sided half-density line. Two splitters to balance the outside lane with the adjacent inside lane, then split off of both edge lanes and edge-insert into the branch line. You can tunnel the wrong-side splitter under the bus with one tunnnel, or reduce the width of the junction by one by tunneling the outer lanes of the bus under the crossover, or make it prettier by tunneling the entire bus under the crossover.

Smallest I think I can do it is 4 splitters, 3 conveyors, 3 tunnels, extending the footprint out by 1 on each side for 3 tiles on the offside and 2 on the branch side.

That won't actually compress the load, but it will let you take the maximum of half of the bus or half of one belt regardless of the current throughput of the belt without reducing it.

In ascii:
..s>^..
>ss\^/>
>s>\^/>
>s>\^/>
>ss\^/>
..s>^<.

s is a splitter >,<,^ are conveyers of the direction, \/ tunnel entrance and exit.

When you have taken enough branches off the bus to narrow it, I think a small mod can be used to break off an entire belt with half the total throughput, capped at either a half belt or full belt.