For those interested, a fairly comprehensive book on backyard metalcasting from scrap (from the ground up) is David Gingery's Build Your Own Metal Working Shop from Scrap https://www.thriftbooks.com/w/build-your-own-metal-working-s...

Starting with green sand, scrap metal, charcoal, and a pot, pour parts to build a lathe, and so on.

It looks like he has put out quite a few "how to" books: https://www.thriftbooks.com/a/david-j-gingery/381968/