Dremel 8220 Original Instructions Manual page 22

be at least equal to the maximum speed marked on
the power tool. Grinding accessories running faster
than their rated speed can break and fly apart.
d. The outside diameter and the thickness of your
accessory must be within the capacity rating of
your power tool. Incorrectly sized accessories cannot
be adequately controlled.
e. The arbour size of wheels, sanding drums or any
other accessory must properly fit the spindle or
collet of the power tool. Accessories that do not
match the mounting hardware of the power tool will run
out of balance, vibrate excessively and may cause loss
of control.
f. Mandrel mounted wheels, sanding drums, cutters
or other accessories must be fully inserted into
the collet or chuck. If the mandrel is insufficiently
held and/or the overhang of the wheel is too long, the
mounted wheel may become loose and be ejected at
high velocity.
g. Do not use a damaged accessory. Before each use
inspect the accessory such as abrasive wheels for
chips and cracks, sanding drum for cracks, tear or
excess wear, wire brush for loose or cracked wires.
If power tool or accessory is dropped, inspect for
damage or install an undamaged accessory. After
inspecting and installing an accessory, position
yourself and bystanders away from the plane of
the rotating accessory and run the power tool at
maximum no-load speed for one minute. Damaged
accessories will normally break apart during this test
time.
h. Wear personal protective equipment. Depending
on application, use face shield, safety goggles or
safety glasses. As appropriate, wear dust mask,
hearing protectors, gloves and workshop apron
capable of stopping small abrasive or workpiece
fragments. The eye protection must be capable of
stopping flying debris generated by various operations.
The dust mask or respirator must be capable of
filtrating particles generated by your operation.
Prolonged exposure to high intensity noise may cause
hearing loss.
i. Keep bystanders a safe distance away from work
area. Anyone entering the work area must wear
personal protective equipment. Fragments of
workpiece or of a broken accessory may fly away and
cause injury beyond immediate area of operation.
j. Hold power tool by insulated gripping surfaces
only, when performing an operation where the
cutting accessory may contact hidden wiring.
Cutting accessory contacting a "live" wire may make
exposed metal parts of the power tool "live" and could
give the operator an electric shock.
k. Always hold the tool firmly in your hand(s) during
the start-up. The reaction torque of the motor, as it
accelerates to full speed, can cause the tool to twist.
l. Use clamps to support workpiece whenever
practical. Never hold a small workpiece in one
hand and the tool in the other hand while in use.
Clamping a small workpiece allows you to use your
hand(s) to control the tool. Round material such as
dowel rods, pipes or tubing have a tendency to roll
while being cut, and may cause the bit to bind or jump
toward you.
m. Never lay the power tool down until the accessory
has come to a complete stop. The spinning
accessory may grab the surface and pull the power
tool out of your control.
n. After changing the bits or making any adjustments,
make sure the collet nut, chuck or any other
adjustment devices are securely tightened. Loose
adjustment devices can unexpectedly shift, causing
loss of control, loose rotating components will be
violently thrown.
o. Do not run the power tool while carrying it at your
side. Accidental contact with the spinning accessory
could snag your clothing, pulling the accessory into
your body.
p. Regularly clean the power tool's air vents. The
motor's fan will draw the dust inside the housing and
excessive accumulation of powdered metal may cause
electrical hazards.
q. Do not operate the power tool near flammable
materials. Sparks could ignite these materials.
KICKBACK AND RELATED WARNINGS
Kickback is a sudden reaction to a pinched or snagged
rotating wheel, sanding band, brush or any other
accessory. Pinching or snagging causes rapid stalling
of the rotating accessory which in turn causes the
uncontrolled power tool to be forced in the direction
opposite of the accessory's rotation.
For example, if an abrasive wheel is snagged or pinched
by the workpiece, the edge of the wheel that is entering
into the pinch point can dig into the surface of the material
causing the wheel to climb out or kick out. The wheel may
either jump toward or away from the operator, depending
on direction of the wheel's movement at the point of
pinching. Abrasive wheels may also break under these
conditions.
Kickback is the result of power tool misuse and/or incorrect
operating procedures or conditions and can be avoided by
taking proper precautions as given below.
a. Maintain a firm grip on the power tool and position
your body and arm to allow you to resist kickback
forces. The operator can control kickback forces, if
proper precautions are taken.
b. Use special care when working corners, sharp
edges etc. Avoid bouncing and snagging the
accessory. Corners, sharp edges or bouncing have
a tendency to snag the rotating accessory and cause
loss of control or kickback.
c. Do not attach a toothed saw blade. Such blades
create frequent kickback and loss of control.
d. Always feed the bit into the material in the same
direction as the cutting edge is exiting from the
material (which is the same direction as the chips
are thrown). Feeding the tool in the wrong direction
causes the cutting edge of the bit to climb out of the
work and pull the tool in the direction of this feed.
e. When using rotary files, cut-off wheels, high-speed
cutters or tungsten carbide cutters, always have
the work securely clamped. These wheels will grab
if they become slightly canted in the groove, and can
kickback. When a cut-off wheel grabs, the wheel itself
usually breaks. When a rotary file, high-speed cutter
or tungsten carbide cutter grabs, it may jump from the
groove and you could lose control of the tool.
SAFETY WARNINGS SPECIFIC FOR GRINDING AND
ABRASIVE CUTTING-OFF OPERATIONS
a. Use only wheel types that are recommended
for your power tool and only for recommended
applications. For example: do not grind with the
side of a cut-off wheel. Abrasive cut-off wheels are
intended for peripheral grinding, side forces applied to
these wheels may cause them to shatter.
b. For threaded abrasive cones and plugs use only
undamaged wheel mandrels with an unrelieved
shoulder flange that are of correct size and length.
Proper mandrels will reduce the possibility of breakage.
c. Do not "jam" a cut-off wheel or apply excessive
22