& COUNTERSINK TERMS:
ACTUAL SIZE: The
actual measured diameter of a counterbore, often somewhat larger than the
AXIAL RAKE: The
angle between a plane containing the cutting face, or tangent to the cutting
face at a given point, and the axis of an angularity fluted counterbore.
AXIAL RELIEF: The
relief measured in the axial direction between a plane perpendicular to the axis
and the relieved surface.
imaginary straight line, which form the longitudinal centerline of a
tooth or cutting device inserted in a counterbore body.
BODY DIAMETER CLEARANCE:
That portion of the land that has been cut away so it will not rub against the
walls of the hole.
The space provided behind the cutting edge or margin to eliminate undesirable
contact between the counterbore and the workpiece.
CLEARANCE DIAMETER: The
diameter over the cutaway portion of the counterbore lands.
A detachable cutting portion of an interchangeable counterbore.
A method of enlarging portions of previously formed holes.
The diameter over the margins of a counterbore measured at the cutting end.
CUTTING EDGE: The
leading edge of the land in the direction of cutting.
See preferred term Axial Relief.
axial advance in inches per revolution of a counterbore with respect to the
The length of the flutes of a counterbore, not including the cutter sweep or the
FLUTED HOLDER: A
fluted holding or driving member for a counterbore cutter in an interchangeable
Helical or straight grooves cut or formed in the body of a counterbore to
provide cutting lips, to permit the passage of chips and to allow cutting fluid
to reach the cutting lips.
GAGE LINE: The
axial position on a taper where the diameter is equal to the basic large end
diameter of the specified taper.
trailing edge of the land in the direction of rotation for cutting. 300
HELICAL FLUTES: Flutes,
which are formed in a helical path around the axis of a counterbore.
HELICAL RAKE: The
angle between a plane tangent to the cutting face at a given point on the
cutting edge, and the counterbore axis.
HELIX ANGLE: The
angle, which a helical cutting edge at a given point makes with an axial plane
thru the same point.
to an interchangeable type of counterbore, the extended mounting and holding
member for the cutting element, or counterbore cutter.
The section of a counterbore between adjacent flutes.
See preferred term Body Diameter Clearance.
LAND WIDTH: The
distance between the leading edge and the heel of the land measured at a right
angle to the leading edge.
The axial relief on the end teeth of a counterbore.
LIP RELIEF ANGLE:
The axial relief angle on the end teeth of a counterbore. It is the angle
between a plane perpendicular to the axis and the relieved surface.
end cutting edges of a counterbore, extending from the outside diameter to the
pilot diameter or the pilot hole.
The cylindrical portion of the land, which is not cut away to provide clearance.
A section of reduced diameter connecting shank to body, or connecting other
portions of a counterbore.
Describes a cutting face in rotation whose cutting edge lags the surface of the
PRIMARY RELIEF: The
relief immediately behind the cutting edge or margin. Properly called Relief.
PROJECTED LENGTH: The
total distance the end face of the cutting element of a counterbore extends from
the end of the machine spindle.
RADIAL RAKE ANGLE: The
angle in a transverse plane between a straight cutting face and a radial line
passing thru the cutting edge.
RADIAL RELIEF: Relief
in a radial direction measured in the plane of rotation. It can be measured by
the amount of indicator drop at a given radius in a given amount of angular
angular relationship between the tooth face, or a tangent to the tooth face at a
given point, and a given reference plane or line.
The result of removal of tool material behind or adjacent to the cutting edge to
provide clearance and prevent rubbing (heel drag).
RELIEF ANGLE: The
angle formed between a relieved surface and a given plane tangent to a cutting
edge or to a point on the cutting edge.
The portion of a counterbore by which it is held and driven.
The tapered hole in a spindle, sleeve or counterbore holder, designed to
receive, hold, and drive a tapered shank.
SPIRAL ANGLE: See
preferred term Helix Angle.
See preferred term Helix Flutes.
operation of producing a usually flat surface at the terminal of, and normal to
the axis of a previously made hole.
STEP COUNTERBORE: A
counterbore designed to produce in one operation, two or more counterbored
diameters and seats at different axial locations.
A solid or adjustable collar on the counterbore body or holder for controlling
the depth of the counterboring of a hole.
STRAIGHT FLUTE: A
flute, which forms a cutting edge lying in an axial plane. See Flutes.
SUBLAND COUNTERBORE: A
type of step counterbore, which has independent sets of lands in the same body
section for each diameter.
flatted end of a taper shank, which fits in a slot in the socket.
TANG DRIVE: Two
opposite parallel driving flats on the extreme end of a straight shank.
TAPER SHANK: A
shank made to fit a specified (conical) taper socket.
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