Automatically scales requested ingredients for it's buffer chest each time the machine idles.

The image posted is an example setup, the actual blueprint is just a single assembler. You can swap out the assembler for any other machine, just make sure it has the same settings and wire connections as the original assembler.

Note that it may take some time for the auto requests to balance, as long as your assemblers are turning on and off they'll eventually request enough to keep them on. If you're impatient you can nudge them by manually depositing resources into idle machines periodically.

Instructions

Daisy chain the green output of the top middle decider. This will be your demand signal. Daisy chain a red wire to the long handed inserters, this will be your control signal to enable/disable them based on demand.

When you're done, place a single arithmetic combinator set to RED (each) - GREEN (each). Connect it's red input to your sushi belt, and set it to read contents all belts. If you have a few splitters breaking the connection that's okay; however, the more coverage you have the better bandwidth you'll get. Connect it's green input to the daisy chained demand signal. Connect it's output to the long handed inserters and your resource inputs (belts/inserters). Set your resource inputs to only enable when their requested resource is > 0.

Happy crafting!

(P.S. Each combinator has a description if you're interested in how it works!)