I've been watching videos from the likes of Seco. Personally, I'm into the DIY speaker scene, but here comes the stupid question. What do you do with the metal waste/chips?

https://www.youtube.com/watch?v=1XI9d8DZOEg

as for the speaker side of things again, what does happen with the aluminium waste?

https://www.youtube.com/watch?v=I6_OfPqfg48 - 00:40 onwards