This is what I want:
A setup that sends freshly smelted iron and refined iron to a chest.
When I take x refined iron out of the chest, it will be replaced by x more.
When I take x iron out of the chest, it will be replaced by x more.
Requirement: Only one rotary macerator and only one induction furnace. Nothing more. The logic should send x iron dust or iron to the furnace respectively when it's needed, and only then. And only the right amount.
I want to use either the regulator or retrievulator to make it happen, but thus far I've only ended up pulling hairs out of my head.