Abstract: A knife for a log profile cutting head assembly is detachably secured to a base including a chip directing gullett which in turn is secured to a standard cutting disc. The removable knife is shaped to include a mounting surface oriented to maximize resistance of the knife to forces encountered and includes rectilinear cutting edges which can be sharpened on conventional grinders. A grinding guide integral with the knife and positioned between one cutting surface and the mounting surface overlaps the interface of the knife and base to prevent chip jamming.