Equipped with a 14-inch-diameter blade, the hand-held hydraulic saw featured in this article can make a 10-inch-deep cut. How does it do it? The blade is shaped like a ring. Unlike conventional disk blades, it has no center. The saw's unusual off-center drive propels the blade from its outside edge. The result: cutting depth is no longer limited by the radius of the blade. Deep cuts can be made with a smaller saw and with less overcutting.
The ring saw cuts masonry and reinforced concrete. Before it wears out, its diamond blade normally can cut 2500 to 3000 inch-feet of cured concrete. Blade life varies, of course, with the type of aggregate and amount of steel in the concrete. Water cools the blade. Replacing the blade is simple; you remove two bolts, flip two levers, and set the tension.