Put the item you want to build in the constant combinator; The 5 assemblers below be set to the recipe for each quality level of the item.
By default each level will buffer 4-5 stacks of a item at a quality level, if the next level up isn't full, start to drop items onto the belt for recycling. (We get to 4 stacks, when we are over 4 stacks, if we need to grind for quality, we will). If the higher level quality exists and is 4 stacks, we wont grind.
Request 5x the ingredients into the requestor chest for each assembler.
No quality modules on the legendary assembler.
Using buffers for the output to pull in any items from the network, including quality upgrades from different production quality levels (the legendary output on the epic production line will move to the legendary buffer)
I was actually making my own legendary grinder! But it has some of the problems I personally think is a deal breaker
No easy replacement for the assembler. You need to move everything if you want to put an electromagnetic lab
not modular. Low quality assembly often get clogged while high quality is waiting for stuff, so you need to be able to add more low quality assemblies than high quality.
No easy way to set the buffer. 4 stacks is way too generous, and you way want to lower the buffer for low qualities
not modular. Low quality assembly often get clogged while high quality is waiting for stuff, so you need to be able to add more low quality assemblies than high quality.
From my perspective, it is modular, just throw up another line if you want to double the output of below, but in my quality journey, i've had much bigger gains through enabling all the full build quality paths then by just grinding one quality level
No easy way to set the buffer. 4 stacks is way too generous, and you way want to lower the buffer for low qualities
The Arithmetic combinator at the top of the blueprint on the same line as the constant combinator sets the desired stack volume in one place. For some things I want 5 stacks, some things I want 40 stacks.
I'd love to see how your approaching the problem if you would like to share your design. I just love all the different tradeoffs and methods factorio enables.
You could make this more flexible by routing all the wires going to the assembler into a power pole, so replacing the assembler with a different crafter is easy.
Adding more throuput to lower quality teirs might be as easy as adding more crafters. Alternatively, each crafter might be able to become it's own module, with just one wire connection to other modules and the initial combinators, and the quality be set arbitrarily on each module. If you need more throuput, you can just add another module.
The next step to that is setting the quality of the recipe based on need, with every module always working. Then adding more modules directly increase throuput with no extra thought required.
Pulling the stocked amount out into the constant combinator would be good for readability. Having a readout of stocked amounts might be fun too.