Abstract: A stripping element includes an elongate hold-down bar that fits between adjacent incisor rings on a rotating drum wood incisor and prevents the teeth on the incisor rings from tearing chunks of wood from the piece of lumber as the teeth pull out after having made perforations. The hold-down bar has a planar lower surface which is parallel or slightly angled from the surface of the piece of lumber and is slightly separated from this surface. The apparatus includes a mounting structure that permits changing the distance between the lower surface of the hold-down bar and the surface of the piece of lumber. The stripping element also includes a cleaning pick which removes any wood chunks that become lodged between the incisor rings.

Abstract: An apparatus for applying perforations to wood surfaces is disclosed. The apparatus includes a drum having interspaced incisor rings mounted thereto and a plurality of cleaning members for removing wood residues from the incisor ring teeth. Each cleaning member projects into a space between adjacent incisor rings and is irrotatably secured to the mounting platform of the apparatus. The rotation of the incisor rings relative to the fixed positioning of the cleaning members brings the side surfaces of the teeth into progressive engagement with the adjoining side surfaces of cleaning members creating a scissor action across the teeth surfaces which effectively removes wood residues from the teeth. The apparatus provides for the removal of wood residue away from the spacer rings located in the space between adjacent incisor rings using cleaning members having tapered projections for directing such residue into pockets defined therein.

Abstract: A wood incisor for perforating the surfaces of a rectangularly cross-sectioned elongate board preparatory to preservative treatment is comprised of sets of paired horizontal and vertical drums arranged in a manner to provide a rectangular passageway of adjustable height and width for passing various sized boards, with each drum having a plurality of outwardly protruding cutting teeth. Each set of drums includes a fixed drum which is driven, and an idler drum which is slideable with respect to its associated fixed drum by actuation of positioning hydraulic cylinders to provide the adjustability of the passageway therebetween. Each of the positioning hydraulic cylinders is joined end-to-end with a cushioning hydraulic cylinder which is connected hydraulically to an accumulator tank containing pressurized hydraulic fluid and air. Thus the position of each idler drum relative to its associated fixed drum is responsive to the lateral force imparted to that set of drums by the board passing therebetween.