Mr Rawles & Co.,
I recently found a project on the Kickstarter web site while browsing for good DIY options for brick making machines. The project seems right up any survivalist’s or prepper’s alley in that it involves designing cheap and durable machinery for use after the collapse of civilization, using mostly only scrap metal or other junk. If successful, the end result is going to be an open-source database (and various CDs) containing schematics and instructions for the construction of at least 50 machines and vehicles. These include brick makers, primitive CNC machine tools, tractors etc. (You get the picture.) Eight have been successfully prototyped and another eight are on the way. They hope to test these in the Third World, and from their preliminary tests and schematics it seems like they are well-built and will likely be quite cost-effective, even on the small scale that agrarian villages (or, to use your terminology, a well-prepared retreat) operate on.
Many thanks for opening my eyes ad those of so many others.
God Bless, – Matt A.