My chip extraction vacuum has a little vortex which fits empty milk jugs. When a jug gets full, unscrew it and stick another one on; it's less fuss and mess than just about anything else I've ever seen. And it's also handy for keeping different kinds of waste separate; I've been screwing on a different collection jug whenever I cut something in metal, then going back to a sawdust jug for the next wood carving job.
But today I was at the local scrap place looking to buy stock, and a guy came in to sell a bucket of brass chips. And finally I realized that ringing in my ears was the clue phone.
If I keep separate jugs for different types of metal (which is easy for me because 99% of the time, if I'm cutting metal it's either brass or aluminum) my chip waste becomes saleable scrap. This will drop the materials cost of my metal parts by at least 20%.
Admittedly, this is small potatoes by most standards; I probably generate less than a half-pound of metal chips a day. But this matters, in practical terms. Brass and Aluminum are expensive as stock, and pricey even as scrap. And besides, the engineer in me hates seeing things go to waste anyway.
So why did nobody ever talk about it in all the time I was learning to use the mill, taking CNC classes, learning to use a die grinder, etc....?
The just plain practical, ordinary, obvious realities of running the operation and managing waste. I feel like such an idiot now.