Instruction Manual Glossary of Terms
Glossary of Terms
Abrasive:
A substance used for abrading — grinding, polishing, lapping — such as
the natural materials, corundum, emery, diamond, etc., and the manufactured or
electric furnace materials, such as: aluminum oxide (Al
2
O
3
), silicon carbide (SiC),
boron carbide (B
4
C), and cubic boron nitride (BN).
Absolute Accuracy:
Conformity in dimension to an exact standard or reference zero.
Accurate:
Made within the tolerances allowed.
Adapter:
A tool holding device or sleeve for the fitting together of parts, shafts,
shanks, etc., having different sizes or tapers. Widely used for milling-machine
cutting tools to make them interchangeable for mills or tool maintenance machines.
Align:
Adjusting to given points.
Alloy:
A mixture of two or more metals fused or melted together to form a new metal
Aluminum:
A silvery-white, very lightweight metal seldom used in pure form It
is made from bauxite ore.
Aluminum Oxide:
An abrasive made by fusing the mineral Bauxite (Al
2
O
3
).
Angle:
The amount of opening or divergence between two straight lines that meet
at a vertex or that intersect each other. Examples are cutter faces, clearance lands,
or work faces relative to each other.
Annealing:
The process of heating metal to a given temperature (the exact tem
perature and the period the temperature is held depends upon the composition of
the metal being annealed) and cooling it slowly to remove stresses, to induce soft
ness, to refine the structure, to alter physical properties
Apprenticeship:
A period of time agreed upon between employer and apprentice
during which the employer promises to teach the apprentice the fundamentals of
the trade Usually a written agreement is signed by both parties
Arbor:
(grinding) The spindle shaft extension of the grinding machine on which
the wheel is mounted.
Arbor:
(workholding) A shaft or spindle for holding cutting tools.
Arbor Hole:
The hole in a grinding wheel or cutter sized to fit the machine arbor
Arc of Contact:
That portion of the circumference of a grinding wheel touching the
work being ground.
Area of Contact:
The total area of the grinding surface of a grinding wheel in con
tact with the work being ground.
Assembly:
A unit that contains the parts that make up a mechanism or a machine,
such as the headstock assembly of a lathe. A machine may consist of several unit
assemblies.
Assembly Drawing:
A drawing which shows a complete machine or mechanism with
all the parts in correct position and properly labeled or numbered.
Axis:
The center line, real or imaginary, passing through an object about which it
could rotate. A point of reference.
Back Rake:
The angle or slope ground on cutting tools to meet different conditions
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