|End Mill Training - End Mill Design Criteria and Technical Features
A - mill size or cutting diameter
B - shank diameter
C - length of cut or flute length
D - overall length
- Angular Edge - That cutting edge that is a straight line, forming an angle with the cutter axis. The surface produced by a cutting edge of this type will not be flat as is the case with a helical cutting edge.
- Axial Runout - The difference between the highest and lowest indicator reading taken at the face of a cutter near the outer diameter.
- Chamfer - A short relieved flat installed where the periphery and face of a cutter meet. Used to strengthen the otherwise weak corner.
- Chip Breakers - Special geometry of the rake face that causes the chip to curl tightly and break.
- Chip Splitters - Notches in the circumference of a Corn cob style End mill cutter resulting in narrow chips. Suitable for rough machining.
- Core Diameter - The diameter of a cylinder ( or cone shape with tapered End mills) tangent to the flutes at the deepest point.
- Counterbore - A recess in a non-end cutting tool to facilitate grinding.
- Cutter Sweep (Runout) - Material removed by the fluting cutter (or grinding wheel) at the end of the flute.
- Cutting Edge (A) - The leading edge of the cutter tooth. The intersection of two finely finished surfaces, generally of an included angle of less than 90 degrees.
- Cutting Edge Angle - The angle formed by the cutting edge and the tool axis.
- Differential pitch cutters - A specifically designed variation in the radial spacing of the cutter teeth. This provides a variation in tooth spacing and can be beneficial in reducing chatter. This concept is based on reducing the harmonic effect of the tool contacting the part in an exact moment of vibration.
- Entrance Angle - The angle formed by a line through the center of the cutter at 90 to the direction of feed and a radial line through the initial point of contact. As this angle approaches 90 degrees the shock loading is increased.
- Entrance Angle: Ramp-in - Angle or radius value to enter the cutter into the part surface
- Fillet - The radius at the bottom of the flute, from which core diameter is found.
- Flute - Space between cutting teeth providing chip space and regrinding capabilities. The number of cutting edges. Sometimes referred to as "teeth" or "gullet". The number on an end mill will determine the feed rate.
- Flute Length - Length of flutes or grooves. Often used incorrectly to denote cutting length.
- Shank - Projecting portion of cutter which locates and drives the cutter from the machine spindle or adapter
- Straight Shank - Cylindrical shank, with or without driving flats or notches, often seen on carbide end mills
- Weldon Shank - Industry name for a specific type of shank with a drive and location flat. The flat on the cutter provides positive ( non slip ) driving surface to the End mill.
- Tooth - The cutting edge of the End mill.
- Tooth Face - Also known as the Rake Face. The portion of the tooth upon which the tooth meets the part.