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COMMON HAND TOOLS
AND
THEIR PROPER USE

From Machine Shop Work
by
John T
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shopdawg
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com

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CONTENTS
HAMMERS
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4
WRENCHES
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9
THE HACK SAW
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Machine shop work is usually understood to include all cold metal
work in which a portion of the metal is removed, either by powerdriven or hand tools, to make the piece of the required shape and
size
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As the hand-operated tools are much simpler, and as the operations
performed with them are in every case more typical, their description and use should precede that of power-driven tools
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Even hand tools are not
used in the same order on different classes of work; it is, therefore,
impossible to describe them in the order of use
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HAMMERS
Classification
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1
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The cross peen and
straight peen hammers vary from 4 ounces to 2 pounds and are
used principally in riveting
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The eye is elliptical in shape, and
the handle is fastened by driving wedges, either wood or iron, into
the end of the handle, thus spreading it to fill the eye
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When the handle is properly inserted,
the axis of the head stands at right angles to the axis of the handle
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Soft hammers are used for striking heavy blows where the steel

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hammer would bruise the metal or mar the surface
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They are subject to rapid wear, but are indispensable in setting up and taking down machinery
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Make sure the head is fastened securely
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A loose hammer head is
dangerous
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Grasp the hammer firmly near the end of the handle
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Start all work with light blows to get it started properly
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Therefore it is necessary for the toolmaker
to have one or more screw drivers to drive these screws or to remove them
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Fig
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The blade section is made of forged carbon tool steel, heat treated
to give the hardness and toughness needed to withstand the twisting motion employed in driving a screw
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The stubby ball-handle screw driver is used on jobs where there is
little clearance
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With this type of screw driver it is possible
to handle large size screws
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For this purpose a piece of drill rod
is used
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Often a square or flat is
milled on the shank so a wrench can be used for added leverage
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Offset Screw Drivers
This screw driver, Fig
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Four blades cover eight different positions of
the screw slot
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How To Use Screw Drivers
1
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4 and 5
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With the right hand, grasp the handle
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6
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Tightening large screws
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See
Fig
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Pressure must be kept on the handle to keep the tip in the
slot
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Do not strike the handle of the screw driver with a hard object
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5
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6
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Questions
1
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Why are screw driver blades made from carbon tool steel?
3
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How is a screw driver blade hardened? Why?
5
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How should a screw driver be held?
7
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What method can be used to make the tightening of large screws
easier?
9
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What might cause a screw driver to jump from the screw slot?
Wrenches
Many different types of wrenches are made for turning nuts, bolts,
pipes, etc
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See Fig
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Whenever the correct sizes are available, the open and closed end
types of wrenches are to be preferred to the adjustable wrenches
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Usually,
the handle of a solid wrench is made so that it will give all the leverage the part to be turned will probably stand
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Hence, when a large adjustable or monkey
wrench is used on a small nut or bolt, the part may be broken easily unless proper judgment is exercised
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The wrench should fit closely, Fig
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A loose fitting wrench
will round the corners of the bolt and slip badly, resulting in hand
injuries
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A quick jerk, when tightening a bolt, or a blow with the ball of
the hand when loosening a nut or bolt, Fig
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3
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11
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How To Use Adjustable Wrenches
1
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Be sure jaws are
pointed in
the direction in which the work is to be turned
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Adjust the jaws until they fit the part tightly, as shown in Fig
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Questions

1
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Why are wrench handles made rather short?
3
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In which direction should force be applied to the monkey
wrench?
5
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Is a push or a blow more effective in loosening a tight nut?
7
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Why should a monkey wrench usually not be used around any
precision or production machinery?
The Bench Vise
In order that work may be held rigidly for the performance of hand
operations, the machinist uses what is termed a vise
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The sectional view, Fig
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In the machinist’s vise, both jaws are made of cast iron with removable faces of cast steel
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When holding soft metal, even
the smooth steel jaws would mar the surface; and in such cases it is
customary to use false jaws of brass or Babbitt metal, or to fasten
leather or paper directly to the steel jaws to protect the work
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The common method of fastening a vise to the bench is by means
of the fixed base, although a swivel base, as shown in Fig
...
Another type of vise in common use has a swivel jaw,
which enables it to hold tapered work firmly
...
The height of the vise from the floor depends somewhat
on the class of work to be performed, but a general rule is to have
the top of the jaws about 1 1/2 inches below the point of the elbow

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when standing erect beside the vise
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How To Use The Bench Vise
1
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2
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The false jaws may be made
from copper, brass, lead, or leather
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Place a block below the work, as shown in Fig
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4
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Be careful not to press cylindrical pieces out of round or to crack light pieces and metals
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Never strike the vise handle with a hammer or other object to
tighten it
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Never pound work on the movable jaw
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How are false jaws held on the regular vise jaws?
2
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From what materials are soft, false jaws made?
4
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Which jaw is movable; which is fixed?
6
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Give three important directions for clamping work
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Hack saw frames are either fixed or adjustable
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Tension is applied to the blade to
make it taut by means of a wing nut on the pistol grip type frame
or by turning a threaded handle on the straight handle type
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16
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Hack saw blades are made from high-grade steels, hardened and
tempered
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Some
blades, however, are more flexible because only the teeth are hardened, leaving the blade comparatively flexible
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Pitch refers to the number of teeth per inch
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Pitch is always the most important factor to consider when cutting
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See Fig
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The most important consideration in the use of the hacksaw is the
selection of the proper blade
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Table 1
shows the proper pitch for various types of materials
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1
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Cutting close to the vise

prevents the stock springing
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18
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To start the saw cut in the right place, make a small nick in the
stock with the edge of a file
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Hold the frame handle securely in the right hand
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Hold the front end of the frame with the
left hand to guide the saw and to give pressure when sawing
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Keep the cut straight
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5
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Because
the teeth point away from the operator, the forward stroke is the
cutting stroke
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6
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The new blade is always thicker than a worn blade;
hence, the new blade will bind if used to continue an old cut
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Do not use oil as a hack saw lubricant in hand sawing
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To saw thin stock, clamp the, stock between two pieces of wood
or soft steel and saw through all three pieces
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Four common causes that break saw blades are as follows:

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(a) Using too coarse a blade on thin stock
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(c) Exerting too much pressure
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3
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The new blade will probably break if forced into the old cut
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The following suggestions are given for holding the work in the
vise properly:
(a) Expose as much of the work as possible so that the maximum
number of teeth may be engaged in the cutting
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(c) Always start the cut with the least possible angle facing the
thrust of the saw teeth
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(d) To prevent chattering, saw as close as possible to the vise
where work is held
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Do not use excessive pressure and saw carefully when the saw is
almost through the cut
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Which stroke is the cutting stroke?
2
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Does the saw cut on the return stroke?
4
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In what position should a piece of flat stock about ¼ inch by 1
inch be placed in the vise for cutting?
6
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7
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What general rules or principles can you give for selecting
blades of proper pitch?



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