Synopsis: Jim Barefoot says what matters most in making chairs is comfort and strength. He describes how to apply upholstery and advises that beginners be ready to rework it to get the right fit. The seat he explains how to make has a slight curve and doesn’t rest on all the rails, so it has to have strength of its own. In cutting and fitting the core of the seat frame, he laminated the seat in a vacuum press from four pieces of 1/8-in plywood and made a cutout where the tailbone would fall. Then he explains how stretched webbing absorbs and releases energy and eases the load on the foam. Photos shows how to stretch and weave the webbing. He uses foam densities of at least 2.1 lb. per cu. ft. for slip seats and explains how the stiffness is measured and how to order it. Then he lays…