Dove-tail end mill having replaceable cutter inserts

A dove-tail end milling tool for milling dove-tail slots having angulated undercut shoulder surfaces and a planar bottom surface, comprising:

• (a) a tool shank defining a longitudinal axis and having a milling head at one end thereof, said milling head defining a plurality of cutter stations oriented in equally angularly spaced relation about said longitudinal axis;
• (b) each of said cutter stations having a generally planar, generally triangular cutter support surface of a dimension for stable support of said cutter insert and being oriented in angular relation with said longitudinal axis;
• (c) a replaceable, generally triangular cutter insert composed of durable metal cutting material and defining three cutting edges being oriented in angular relation with one another, said three cutting edges having included angles of 60.degree. with one another and being less than the angle of the angulated undercut shoulder surface with the planar bottom surface of the dove-tail slots, said cutter insert having a cutting rake of about plus 15.degree., an axial rake angle of about plus 10.degree. and a radial rake angle of about minus 14.degree.;
• (d) a locator shoulder being defined by said milling head and being engaged by one of said cutting edges for accurately positioning a second of said three cutting edges of said cutter insert for cutting said undercut shoulder surfaces of said dove-tail slot and for positioning a third of said three cutting edges of said cutter insert for cutting said planar bottom surface of said dove-tail slot and for positioning said third of said three cutting edges for cutting said planar bottom surface and defining a clearance angle of said third of said cutting edges with said planar bottom surface;
• (e) a retainer screw extending through said cutter insert and into said cutter station for retaining said cutter insert in releasable assembly with said milling head at said cutter station with two of said three cutting edges exposed for simultaneous milling of said planar bottom surface and at least one of said angulated undercut shoulder surfaces and with one of said cutting edges oriented at a clearance angle with the planar bottom surface of the dove-tail slot.

A dove-tail end milling tool for milling dove-tail slots having angulated undercut shoulder surfaces and a planar bottom surface, comprising:

• (a) a plurality of replaceable, triangular cutter inserts composed of durable metal cutting material and defining three cutting edges being oriented in equal angular relation with one another and having included angles of 60.degree. with one another;
• (b) a tool shank defining an axis of rotation and having a milling head at one end thereof, said milling head each having a plurality of cutter stations having a generally planar, generally triangular cutter support surface of a dimension for stable support of said one of triangular cutter inserts, each of said cutter stations having a locator shoulder being defined by said milling head and being engaged by one of said cutting edges of said triangular cutter insert for accurately positioning a second of cutting edges of said cutter insert for cutting said undercut shoulder surface of said dove-tail slot and positioning a third of said cutting edges for cutting the planar bottom surface of the dove-tail slot and;
• (c) retainer screws extending through each of said cutter inserts and into said cutter stations for retaining said cutter insert in releasable assembly with said milling head at said cutter station;
• and
• (d) said locator shoulder orienting one cutting edge of said cutter insert for cutting undercut dove-tail shoulder surfaces at a designated angle and orienting an adjacent cutting edge of said cutter insert at a clearance angle with respect to the planar bottom surface being generated by said cutter insert and accomplishing positioning of said cutter insert at a cutting rake angle of about plus 15.degree., a axial rake angle of about plus 10.degree. and a radial rake angle of about minus 14.degree..