Each input produces 1.875 atoms (1 quicksilver, .875 copper)
Each output contains 17 atoms (5 quicksilver, 6 copper, 6 either)
The lowest whole multiple of 17 and 1.875 is 255
136 inputs produce 255 atoms
255 atoms make 15 outputs
I put 15 arms on 136 track, using the same track for both pipelines