Milwaukee Tool 2680-22 - Manual (Page 5)

8 9
Fig. 7 Wire Cup Brush
WARNING To reduce the risk of injury,
the operator should be instructed in the use,
care and protection of grinding wheels.
Fig. 5
For best result use only this portion of disc
Hold at a Hold at a
5° to 15° 5° to 15°
angle angle
USING GRINDING WHEELS
Grinding Wheel Selection
Use grinding wheels, and accessories that are:
• correct size as written on tool’s nameplate.
• rated at or above the RPM listed on the tool’s
nameplate.
• correct accessory, wheel type and grit for the job.
Grinding is the cutting action of thousands of abra-
sive grains on the face of a grinding wheel. When
grinding metals such as steel and iron, choose an
aluminum oxide grinding wheel. Select a silicon
carbide grinding wheel for stone and concrete. Use
cotton reinforced wheels for non-ferrous metals.
Type 27 Reinforced 1/8" thick or less Cut-Off
Wheels are suited for small cut-off and shallow
notching operations only. Always handle wheels
carefully to avoid damage. Before installing any
wheel, always inspect it for cracks. If wheel is
cracked, discard it to prevent others from using it.
Care of Grinding & Cut-Off Wheels
Grinding/cut-off wheels should be protected from:
• wetness and extreme humidity
• any type of solvent
• extreme changes in temperature
• dropping and bumping
Grinding and cut-off wheels should be stored:
• in an organized way so wheels can be removed
without disturbing or damaging other wheels
• with their safety information
Grinding and cut-off wheels should NOT be
dropped, rolled or bumped.
Discard wheels that have been dropped, rolled,
bumped, subjected to extreme changes in tem-
perature, or come into contact with solvents or
wetness.
Grinding
When grinding, hold tool at a 5
o to 15 o angle, using
constant pressure for a uniform fi nish. Too great an
angle causes concentrated pressure on small areas
which may gouge or burn work surface.
Wire
Wheel
Brush
Fig. 8 Guard
WARNING Everyone in the area must
wear protective clothing and safety goggles
or face shields. Fatigued wires and residue
will fl y off the brush with considerable force,
causing potential for serious injury.
WARNING Never exceed Maximum
Safe Operating Speed of brush. Do not use
a damaged brush or one that is functioning
improperly (throwing wires, out-of-balance,
etc.). These conditions increase the pos-
sibility of further brush failure and possible
injury. Discard and replace damaged brushes
immediately.
USING WIRE BRUSHES
Wire brushes are useful for removing rust, scale,
burrs, weld slag, etc.
Always install wire cup brushes according to the
accessory manufacterer’s instructions.
Test wheel for balance and loose or damaged wires
by letting it spin for one minute before applying it
to the workpiece. During this time, no one should
stand in front of or in line with it.
Control pressure and surface contact between
wheel and workpiece. Too much pressure causes
over-bending of wires and heat build-up causing
premature wire breaking, rapid dulling and reduced
brush life. Instead of more pressure, try a wire wheel
with more aggressive cutting action (increased wire
size, decreased wire length or different brush type
(knot type vs.crimped wire type).
When using a wire wheel brush, install guard ac-
cording to "Installing/Removing Accessories".
WARNING Because the wires on wire
wheel brushes are directed towards the op-
erator, a guard must be used to protect the
operator when fatigued wires break.
Aluminum Oxide
For fast cutting, general purpose discs for most
metal jobs. Best for cold-rolled steel, stainless
steel or metals requiring tough, fast cutting, long
lasting abrasives.
Aluminum Zirconia Bi-Cut
Unique grit pattern is arranged in clusters for fast-
er stock removal and cleaning. Ideal for removing
paint from cars, boats, etc. without clogging.
Ceramic
Lasts up to 3 times longer than Aluminum Ox-
ide Discs. For general metal working. Ideal for
tough jobs.
Sanding Disc Selection
Use sanding discs and accessories that are:
• correct size as written on tool’s nameplate.
• rated at or above the RPM listed on the tool’s
nameplate.
• correct accessory, wheel type and grit for the job.
Refer to the table below to select the correct type
of sanding disc for your job. Generally, use 24 or
36 grit for heavy stock removal; 50, 60, or 80 grit
for medium stock removal and 120 grit for fi nishing.
Always begin with a coarse grit, using successively
fi ner grits to obtain the desired fi nish. See your
MILWAUKEE Electric Tool Catalog for a complete
list of sanding discs.
USING SANDING DISCS
Installing Backing Pad and Sanding Discs
1. Remove the battery pack.
2. Wipe the accessories, disc nut and spindle to
remove dust and debris. Inspect the parts for
damage. Replace if needed.
3. Slip backing pad onto spindle with fl at side away
from gear case.
4. Place sanding disc on backing pad and secure
assembly to spindle with disc nut.
Fig. 9
Spindle
Backing
pad
Disc nut
Sanding
disc
5. To tighten, press the spindle lock button while
turning disc nut clockwise with the spanner
wrench provided.
6. To remove backing pad and sanding disc,
remove the battery pack and reverse the pro-
cedure.
Sanding
Hold tool at 5° to 15° angle to ensure proper sand-
ing pressure and control. Too great an angle will
result in too much pressure and could cause exces-
sive wear to the disc and workpiece. Too small an
angle will reduce control.
Use long, sweeping, side to side strokes, advancing
forward to produce the desired fi nish.
Cross Sanding
When fi nishing a surface that has been prepared
by a coarse disc or wheel, sand at right angles
to the strokes made by the coarser disc. Finish-
ing marks left from previous sanding are easily
seen and removed for a uniform fi nish. Failure to
cross sand when changing from a coarse disc to
a fi nishing disc may result in deep scratches and
circular marks.
Removing Welds or Hammer Marks
When removing welds or hammer marks, limit
coarse sanding to the immediate area. Use suc-
cessively fi ner grits to smooth surface.
Finishing Metal
Constantly move across the surface. Work faster on
curved surfaces where contact areas are smaller
and pressure is greater. Flat areas may appear at
the end of the stroke when pressure is too heavy.
Ease up on pressure at end of each stroke and
when reversing strokes.
Troubleshooting
Deep scratches and circular marks can result
from:
• Using too coarse a grit
• Using a partially glazed disc
• Dirt or loose metal on the workpiece
• Failure to sand across the grain when changing
from coarse to fi nishing discs
• Failure to use closed coated discs to reduce the
problem of grains working loose and scratching
the workpiece
Bluish discoloration of metal surface indicates:
• Excessive heat caused by circular motion in a
small area
• Excessive pressure
• Use of worn out or glazed discs
Fig. 10
For best result use only this portion of disc
Hold at a Hold at a
5° to 15° 5° to 15°
angle angle