We all love Fulgora, right? Except it can be a bit of a mess to balance the output from scrap recycling. You end up sending too much gears to your storage, or overfilling your beautiful sushi belt.
Part of the challenge is dealing with this, and my personal tendanciy is to take only what I need, and dispose of the rest at the source.
Therefore, I present my scrap recycling system, along with it's control switch.
This little beast will eat through scrap at a terrifying pace, then sorts out what your base needs, and send the rest to a second set of recyclers, where other sub-products are extracted as needed. Any subproducts from this second round of recycling are looped back into the second set of recyclers.
-processes a fully stacked turbo belt (240 items/sec). The output belt from the first recycling complex can be a limiting factor, but I just pop more of these in parrallel if the throughput is not enough.
-All wares are output fully stacked.
-It fits into a regular grid of substations, with a 9x1 "tile" footprint.
-It comes with a very simple control module that can be fitted to your storage, sushi belt, or whatever you use. I'm using radars to transmit the signal, but you can replace them with regular wires if you are already using the radar signals for something else.
-It will also stop the main scrap input in case no wares are needed. But if that ever happens, well... my friend, your factory is not growing.
-I left out the iron ore recovered from recycling concrete. It has no use for me, and therefore is getting eliminated on the spot
Here's the BP for the recycler itself. They are easy to set up in parrallel depending on your need. Can the design be improved? Yes! But it works well enough for me for now.
Here's the blueprint of the controller. Just hook the electric post to your storage or sushi belt, and set the desired amout of each wares in the constant combinator. I use the red wire on the post to get a visual reading of the output when needed, but otherwise it served no purpose.
I made the stupid executive decision to build a bunch of them outside my base and make a sushi train to deliver the wares to my main storage. Had lot of fun setting this up.

I also had an "early game" version with unstacked red belts, but never optimised it enough to the point where I wanted to post it.
Peace!