SCALE --The ratio between the measurement used on
HONING--Finishing machine operation using stones
vice a tool bit or cutting tool.
a drawing and the measurement of the object it
represents. A measuring device such as a ruler,
INVOLUTE --Usually referred to as a cutter used in
having special graduations.
SECTOR--A figure bounded by two radii and the
KNOOP --Trade name used in hardness testing.
included arc of a circle, ellipse, or other central
MANDREL--Tool used to mount work usually done
SPOT FACING--Turning a circular bearing surface
about a hole. It does not affect a pattern.
proximately 100°F above the critical temperature
STANDARD CASING--The half of a split casing that
range followed by cooling to below that range in
is bolted to the foundation, as opposed to the half,
still air at room temperature.
or cover, which can be removed with minimum
PERPENDICULAR --A straight line that meets
disturbance to other elements of the equipment.
another straight line at a 90 degree angle. Also a
STRAIGHTEDGE --Relatively long piece of material
vertical line extending through the outline of the
whose working edge is a true plane.
hull ends and the designer's waterline.
STRENGTH --The ability of a material to resist strain.
PIG IRON--Cast iron as it comes from the blast
furnace in which it was produced from iron ore.
STRESS RELIEVING--Heat treatment to remove
stresses or casting strains.
PINHOLE --Small hole under the surface of the
STUD--(1) A light vertical structure member, usually
of wood or light structural steel, used as part of a
PLAN--A drawing prepared for use in building a ship.
wall and for supporting moderate loads. (2) A bolt
threaded on both ends, one end of which is screwed
to be excessively and permanently deformed
into a hole drilled and tapped in the work, and used
where a through bolt cannot be fitted.
PREHEATING --The application of heat to the base
SYNTHETIC MATERIAL--A complex chemical
metal before it is welded or cut.
compound that is artificially formed by the
PUNCH, PRICK--A small punch used to transfer the
combining of two or more simpler compounds or
holes from the template to the plate. Also called a
TEMPER --To relieve internal stress by heat treating.
QUENCHING --Rapid cooling of steels at different
TEMPLATE --A pattern used to reproduce parts.
TOLERANCE--An allowable variation in the
REAMING--Enlarging a hole by revolving in it a
dimensions of a machined part.
cylindrical, slightly tapered tool with cutting edges
VICKERS --A scale or test used in metal hardness
running along its sides.
RECHUCKING --Reversing of a piece of work on a
VITRIFIED BOND--A man-made bond used in
faceplate so that the surface that was against the
faceplate may be turned to shape.
WAVINESS--Used as a term in the testing finish
REFERENCE PLANE--On a drawing, the normal
plane from which all information is referenced.
machining of parts.
RPM --Revolutions per minute.
ZINC--An alloy used widely in die casting.