One of my neighbours makes models of railway locomotives. Pretty undemanding stuff? Well, no. He scratch builds them from the engineering blueprints. Has an unbelievable model of a BR Battle of Britain class loco. It is about 1/20th scale, some 3ft long. He made every part from scratch, in metal. Wheels, for example, were cut from solid block of metal and milled down to size and shape on lathe. No pre-made parts whatsoever. Every bit hand-made.