Grinding Operations; Selecting Grinding Wheels; Disc Grinding Wheels; Cutting Metal - Bosch 1380 SLIM Operating/Safety Instructions Manual

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SELECTING GRINDING WHEELS

Before using a grinding wheel,
be certain that its maximum
safe operating speed is not exceeded by the
nameplate speed of the grinder. Do not exceed
the recommended wheel diameter.

DISC GRINDING WHEELS

Grinding wheels should be carefully selected in
order to use the grinder most efficiently. Wheels
vary in type of abrasive, bond, hardness, grit
size and structure. The correct type of wheel to
use is determined by the job. Use disc grinding
wheels for fast grinding of structural steel,
heavy weld beads, steel casting, stainless steel
and other ferrous metals.
GRINDING TIPS
Efficient grinding is achieved by controlling the
pressure and keeping the angle between wheel
and workpiece at 10° to 15°. If the wheel is flat,
the tool is difficult to control. If the angle is too
steep, the pressure is concentrated on a small
area causing burning to the work surface.
SELECTING SANDING DISC
Sanding discs are made of extremely hard
and sharp aluminum oxide grits, phenol-resin
bonded to a sturdy fiber backing for fast
heavy-duty service and long life. The discs
vary as to size and spacing of the abrasive
grits. OPEN COAT (type H) — used for soft
materials and on paint or varnish. CLOSED
COAT (type K) —used for metal, hardwood,
stone, marble and other materials.
Sanding discs range in grit from 16 (very
coarse) to 180 (very fine). To obtain best
results, select sanding discs carefully. Many
jobs require the use of several grit sizes and

Grinding Operations

grinding action and put dangerous stresses on
the wheel.
When grinding with a new wheel be certain to
grind while pulling tool backwards until wheel
becomes rounded on its edge. New wheels
have sharp corners which tend to "bite" or cut
into workpiece when pushing forward.
Using the optional type 1A wheel guard, it is
possible to perform limited cutting on small
stock such as metal tubes, piping or rebar.
When cutting, work with moderate feed,
adapted to the material being cut. Do not
exert side pressure onto the cutting disc, tilt
or oscillate the tool. When cutting profiles
and square bar, it is best to start at the
smallest cross section.
Always follow precautions for kickback.
Do not apply side pressure to cutting wheel
to reduce wheel speed.
Use silicone oxide wheel.
The tool should always be used so that
sparks are directed away from user.
Sanding Operations
at times both "open coat and closed coat"
discs are required to get the job done faster.
See chart for application examples.
Operation: Refinishing painted wood or metal surfaces.
REMARKS
To remove paint and to smooth
surface irregularities.
To smooth
the rough sanding.
To remove scratches left by
previous discs.
To smooth surfaces for painting,
polishing or waxing.
Excessive or sudden pres-
sure on the wheel will slow

CUTTING METAL

GRIT
Coarse
16-24-30
Medium
36-50-80
Fine
100-120
Very Fine
150-180