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The table saw is one
of the most commonly used stationary power
tools in any woodworking shop. Safe usage requires that it be hand-
led with care and specific procedures be followed to prevent accidents.
Read and understand the warnings and instructions on the saw and in
the owner/operators manual.
Always wear safety goggles
or safety glasses with side shield comp-
lying with current national standard, and a full face shield when needed.
Use a dust mask in dusty work conditions. Wear hearing protection
during extended periods of operation.
Do not wear gloves, loose
clothing, jewelry or any dangling objects that
my catch in rotating parts or accessories. Tie back long hair.
Keep the saw table free
of tool and debris.
Use an auxiliary work
support when sawing long or wide workpieces to
assure firm control of the workpiece at all times.
A table saw should be
equipped with a rip fence, miter gauge, blade guard,
spreader and anti-kickback device. The rip fence must be parallel to the line
of the saw blade to prevent binding and possible kickback (See "Preventing
Table Saw Kickback").
The blade should project
only a minimal distance above the cut - 1/8" to
1/4" is plenty - check your owner/operators manual carefully.
Never reach over or behind
the blade with the table saw operating.
Use the guard on all
operations where the saw blade cuts through the thick-
ness of the workpiece.
When using the table
saw for dadoing, grooving or shaping, use a push-
block to keep your hands and fingers well away from the saw blade in
case of kickback or other unexpected event.
Check often to assure
that guards return to their normal position quickly. If
a guard seems slow to return or "hangs up," repair or adjust it immediately.
Do not cut freehand
(cutting without the use of a miter gauge or rip fence).
When crosscutting, use
the miter gauge to assure a straight cut, not the rip
fence. The cut off piece can bind between the fence and blade, causing
kickback and possible injury.
When ripping, always
use the rip fence to assure a straight cut.
Make sure the blade
and fence are parallel to each other. Pressure to feed
the workpiece (stock) should be against the direction of blade rotation and
between the blade and the fence. Use a pushstick to keep your fingers
away from the saw blade. For special operations (whenever the blade does
not cut through the thickness of the workpiece) such as dadoing and
rabbeting, consult your owner/operators manual.
Use a featherboard to
firmly hold the workpiece against the fence and table
when ripping narrow stock.
Keep your tool blades
sharp. Dull blades can cause binding, possible kick-
back and injury.
Use the correct blade
for the job you are doing. Watch for overly heated or
vibrating blades. Correct the condition before continuing.
Make sure the blade is
installed to rotate in the proper direction. Do not
use grinding wheels, wire brushes, or abrasive wheels on a table saw.
Onlookers should be
kept out of the work areas. They distract the operator
and make him more accident prone. A kickback or a broken carbide tip
could send the stock or the tip flying with unpredictable results.
It is recommended that
you turn the tool off after each completed
procedure.
The saw should always
be turned off and unplugged before making
adjustments of any kind.
Turn off, unplug when
possible, and lock the table saw after each use.
Remove and store the switch or lock key.
PREVENTING
TABLE SAW KICKBACK
Kickback is the ejection of the workpiece from the saw back towards the
operator. Table saw kickback may be caused by:
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the
kerf of the workpiece closing up and pinching the rear of the
saw blade. |
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wedging of the workpiece between the fence and the rear of the
saw blade (fence not parallel with saw blade). |
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a crooked
cut which causes the workpiece to bind against the
sides of the blade as it passes through. |
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edge
of a workpiece against the fence not straight. |
When binding, pinching
or wedging occur the motion of the saw blade tends
to lift the wood and may hurl it back toward the operator.
Specific safety precautions
in preventing kickback when using table saws are
given below:
Always use the spreader
(splitter) when it is functional. This prevents the kerf
from closing and pinching the blade.
Make sure the spreader is properly
lined up behind the blade.
Always use the anti-kickback
pawls (fingers). If a kickback should occur they
are designed to grab the workpiece and prevent it from being thrown back toward
the operator. Keep the teeth of the pawls (fingers) sharp.
Anti-kickback devices
may not work when cutting smooth or hard surfaces.
Therefore always cut with the smooth, hard surface next to the table.
Always use the rip fence
to guide the workpiece in a straight line when ripping.
Never freehand cut a
workpiece. Freehanding causes crooked cuts and potential
kickback. Crooked edges on the stock can also cause crooked cuts.
Make sure the fence
is parallel to the blade. If the fence closes in toward the
rear of the blade it will tend to wedge the wood against the blade and may
cause kickback.
Never tilt the blade
or saw table such that the workpiece is trapped in the
angle between the blade and the fence. This is a condition which has high
potential of causing kickback. Use the fence to the side of the blade
that
results in an angle greater than 90 degrees between the blade and the table.
Keep the angle between
the blade and fence open so that the workpiece is free to absorb any misalignments.
(See owner's manual for cutting techniques).
Avoid standing directly
behind the workpiece when making a rip cut.
Always use the miter gauge when crosscutting, and hold the workpiece firmly
against it to assure a straight cut.
Other precautions which
should be taken to prevent kickback while using a
table saw:
A dull blade may cause
a kickback. Keep blades sharp.
Make sure set tooth
blades have adequate set. Tooth set provides clearance
between the plate of the blade and the workpiece, thus minimizing the
probability of binding. Some saw blades are hollow or taper ground to
provide
clearance.
Keep saw blades clean.
A buildup of pitch or sap on the surface of the saw blade increases the thickness
of the blade and also increases friction on the blade
surface. These conditions cause an increase in the potential of a kickback.
Do not cut wet wood.
It produces higher friction against the blade. Also the blade
tends to load up with wet sawdust, affecting a much greater probability of
kickback.
Be very careful of stock
which is pitchy, knotty or warped. These are more
likely to create pinching conditions and possible kickback.
Never use a bent, broken
or warped saw blade. The probability of binding
and creating a kickback is greatly increased.
Overheating a saw blade
can cause it to warp and create a kickback. Buildup
of sap on the blades, insufficient set, dullness, and unguided cuts can
all
cause an overheated blade.
Do not use more blade
height than is required to cut the workpiece - 1/8 in.
to 1/4 in. greater than the thickness of the stock is sufficient. This
minimizes
the amount of saw blade exposed.
Never use miter gauge
with the rip fence.
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