@dc42 thanks the railcore looks interesting,
Plastic metal, as to the 10 grand printer that is way out of my price range... I can stretch to a grand or a few hundred more but not that much over.
I am very much in the research mode right now this is something of a retirement hobby for me or I hope it will be. I am into my 70s and not as quick as I once was but I believe in constantly learning new skills to stave off ossification of the brain... I want to put off that event for as long as possible as I have an abiding curiosity about what the future will hold. In the 1950s when we were taught “ duck and cover” at school I never expected that we as a planet would survive without global thermonuclear war to make it into this century and so it’s all bonus time for me