Tc 9-524 fundamentals of machine tools

hot-rolled steel 
- Steel which is rolled to finished
size. while hot. Identified by a dark oxide scale left
on the surface.
idler 
- A gear or gears placed between two other
gears to transfer motion from one gear to the other
gear without changing their speed or ratio.
independent chuck 
- A chuck in which each jaw may
be moved independently of the others.
indexing 
- The process of positioning a workpiece for
machining it into equal spaces. dimensions. or angles
using an. index or dividing head.
indexing fixture 
- A complete indexing unit
composed of a dividing head and rootstock. (See
dividing head.)
index plate 
- A metal disk or plate punched with
many holes arranged in a series of rings. one outside
the other each ring containing a different number of
holes.
indicator 
- A precision instrument which shows
variations of thousandths of an inch or less when
testing the trueness or alignment of a workpiece,
fixture, or machine.
inserted-tooth cutter 
- A milling cutter designed
with replaceable cutting tooth inserts to save the
expense of a new cutter whenever the teeth become
damaged or worn. Generally, they are made 6 inches
or more in diameter.
intermediate gear - 
See idler.
jack, leveling 
- Small jacks (usually screw jacks) for
leveling and holding work on planner beds and
similar places.
Glossary - 10

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TC 9-524
Jacobs chuck 
- Common term for the drill chuck
used in either the headstock spindle or in the tailstock
for holding straight-shank drills, taps, reamers, or
small diameter workplaces.
Jarno 
- A standard taper having 0.600-inch taper per
foot used on some machine tools.