An improved pivotably mountable brushcutter blade, comprising:
- a planar member with opposite parallel planes, having top and bottom sides, and a peripheral edge;
- with the top side facing the brushcutter for mounting, and for rotationally driving the blade in a predefined cutting direction;
- a central hole for mounting;
- a first sector of the planes bounded bilaterally by radii and distally by a first primary arc of an imaginary circle having a center coinciding with the blade center, with at least three cutting teeth capable of cutting in said predefined cutting direction, placed on said first primary arc;
- and
- a second sector contiguous with and in rotational advancement into said predefined cutting direction, positioned directly successive to said first sector, and bounded bilaterally by radii, and distally by a second primary arc of said imaginary circle, with at least three cutting teeth capable of cutting in said predefined cutting direction, placed on said second primary arc;
- and
- a third sector contiguous with and in rotational advancement into said predefined cutting direction, positioned directly successive to said second sector, and bounded bilaterally by radii and distally by a third primary arc of said imaginary circle, with at least three cutting teeth capable of cutting in said predefined cutting direction, placed on said third primary arc;
- and
- wherein said primary arcs of said first, second and third sector, respectively, join secondary arcs of three imaginary circles having centers offset from said blade center such that said secondary arcs form sections radially inward of said primary arcs, and rotationally advanced relative to said primary arcs in said predefined cutting direction and having teeth placed on said secondary arcs capable of cutting into said predefined cutting direction;
- and
- wherein said secondary arcs of said first, second and third sectors, are respectively rotationally aft of, and join a chord section of a rotationally advanced sector to said respective primary arcs, in said predefined cutting direction;
- and
- wherein each said chord section joins the aftmost point of its respective sector to the aftmost point of its respective primary arc;
- and
- comprising on said bottom side of said planar member auxiliary, axial cutting means, located a predetermined distance radially inward from said imaginary circle of said first sector, and radially outward of the blade center mounting hole, and having an unsevered angular juncture with said planar member, and having three sides severed, and extending substantially axially, with an acute angularity to said bottom side planar from the base line juncture, and toward said peripheral edge, and said axial cutting means angularly oriented for cutting in said predefined cutting direction;
- and
- wherein said unsevered angular junctures include a longitudinal orientation substantially into the blade cutting direction;
- and
- wherein said axial cutting means exhibit radial symmetry on said planar member.