Left: A 1951 3 hp Choremaster Model C. Part of Joe Franklin’s collection, the piece includes a sickle bar mower that moves in two directions. Right: Joe’s 1950s-vintage Chain Tred Model C, built in Portland, Ore. “Actually, to me it looks worthless. But it runs great. And I have a blade for it. You could push snow with it,” Joe said wistfully, on a day last July when temperatures neared the century mark.