A chain saw arrangement for cutting flat sides or kerfs on a round log or timber. The arrangement includes a chain saw housing at a first end of the chain saw. An elongated chain/blade supporting frame extends from the chain saw housing. A multi-tooth chain/blade is movably supported from the elongated frame. A support bracket is secured to one side of the elongated frame for providing restricted support of the chain/blade on a log or timber during cutting of a transverse kerf thereon.