Some of you have mentioned many "Tools of the Month" are rather pricey for the average sometimes do-it-yourselfer, and we agree. It costs money to have a home shop. But it costs more money to pay a ...

This article was originally published with the title “Demagnetizer, Induction Hardening, and more” in Scientific American Magazine Vol. 166 No. 4 (April 1942), p. 203 ...