Christmas challenge: 28 to 24-belt merge

[SpeedDaemon]

My current project (ludicrous # of rockets/second) requires taking the 28-belt output of a factory section, and turning that into 24 belts, so it can pair up with the 24 output belts of two other sections for final assembly at the silos. I think I've already found a good solution, but figured I'd throw it out here to see what other people come up with.

Parameters:
- The input belts are already balanced
- Input belts are already the fastest available
- The input belts must not back up
- This factory section outputs the same items/second as the other two with 24 output belts, so it can be safely assumed that the total item flow will fit on 24 belts.
- The output belts must remain balanced

my solution

Principles:
- 1-to-N splits are fairly easy
- Merges pretty much have to be N/2 to stay balanced

Take 4 of the 28 belts, and do a 1-3 split (easy), then 3-6 (really easy), which leaves 24 of the original belts, and 24 new belts
Pair new & old, and merge back to 24.

[Dr. Walrus]

You could always just divide your belts into 4 sections, and then use a 7 to 8 lane belt balancer followed by 2x 4 to 3 lane belt balancers.

[Jackalope_Gaming]

My first thought was split 4 of those belts into 6, for a total of 30 which is 6 groups of 5. From there do a 5 to 4 compressor on each one which ends up as 6 groups of 4 for the final 24 belts. A 5 to 4 compressor when you're not sure if the belts have equal counts is best done through a modified 8 belt balancer.

Here's one way to do a 4 to 6 using an 8 belt balancer:


Or there's doubling up on a 2 to 3 belt balancer:


And since the 5 lane belt sections probably won't be even you'll need to do a full 5 to 4 compressor which is most accurately done using a modified 8 belt balancer like so:


All of these are based on MadZuri's count perfect belt balancer designs at https://www.reddit.com/r/factorio/comme ... balancers/.

There is also the option of modifying the monster 32 to 32 lane balancer from https://www.reddit.com/r/factorio/comme ... _balancer/ but that might be overkill.