3 posts.
An old truck brake drum, some black-iron pipe and a hair dryer make a coal or charcoal forge hot enough to shape steel. Build steps, the heat-color chart, and the safety rules blacksmiths learned the hard way.
With a fish tank, 99% isopropyl alcohol, felt and a slab of dry ice you can watch muons from space streak through your garage. Parts list, build steps, and how to tell the tracks apart.
Strip heavy rust off tools, parts and cast iron with a plastic tub, washing soda, scrap steel and a battery charger. Step-by-step setup, the polarity that matters, and the safety rules.