The United States Navy Foundry Manual was a navy field manual designed to allow naval personnel aboard ship to reproduce vital parts without having to wait on resupply. It has a huge amount of information, but is written so that even a squid can understand it.
I find this book to be a huge help in designing molds for casting metal parts in my home workshop.
Not only does this book cover mold making, it also covers metallurgy, types of foundries, and a lot more.
This book, along with the gingery series, should be in every prepper’s library. you may never use it, but the knowledge contained within can go a long way toward rebuilding society in a collapse. If you knew how to program industrial machines and cast metal then you could probably do most anything in a grid down collapse.
I have a hard time using my foundry in the small subdivision that I live in, but once I get a shed built down on the land, I hope to get back into casting so I can share the videos with to (as well as build a gingery lathe.