Bosch 1974-8 Instrucciones De Funcionamiento Y Seguridad página 14

BM 1609929T61 07-09:BM 1609929T61 07-09 7/8/09 1:37 PM Page 14
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 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.
SANDING TIPS
For best results, tilt the Disc Sander at a 10° to
15° angle while sanding so that only about 1" of
the surface around the edge of the disc contacts
the work.
Wire brushes are intended to "clean"
structural steel, castings, sheet metal, stone
and concrete. They are used to remove rust,
scale and paint.
Avoid bouncing and snag-
W RNING
ging the wire brush, espe-
cially when working corners, sharp edges
etc. This can cause loss of control and
kickback.
Sanding Operations
If the disc (accessory) is held flat or the back
edge of the disc comes in contact with the work,
a violent thrust to the side may result.
If sander is tilted too much, sanding action will
be too great and a rough cut surface or gouging
and snagging will result.
Guide the Disc Sander with crosswise strokes.
Be careful not to hold the sander in one spot too
long. Do not use a circular motion, as this
makes swirl marks. Test before use on scrap
stock.
Do not force or apply pressure when sanding.
Use only the weight of the tool for pressure.
Excess pressure actually slows the tool down. If
faster stock removal is desired, change to a
coarser grit disc.
Remove gummy paint from metal with an "open
coat" disc. Sand until sparks start to appear,
then stop and change to a "closed coat" disc to
GRIT
remove any remaining paint.
Coarse
16-24-30
When sanding wood the direction of the disc
Medium
motion at the contact point should parallel the
36-50-80
grain as much as possible. The rapid cut of
Fine
discs and the swirl type scratch pattern they
100-120
occasionally create generally prohibit their use
Very Fine
for producing the final finish.
150-180
Scratches and circular marks are usually the
result of using too coarse a grit. When changing
to a finer grit, move across the sanding lines that
were made by a previous coarser disc.
When sanding automobiles or appliances, wipe
the metal clean with a non-flammable solvent or
commercial cleaner to remove all wax and
grease. By doing this first, the sanding discs will
sand better and last longer.
For heavy duty work, use a coarse grit disc first.
Follow-up with a medium grit to remove
scratches. To produce smooth finish, use fine
grit disc.
Wire Brush Operations
W RNING
even during ordinary operation. Do not
overstress the wires by applying excessive
load to the brush. The wire bristles can easily
penetrate light clothing and/or skin.
1. Remember, the tips of a wire brush do the
work. Operate the brush with the lightest
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SANDING WOOD
SANDING METAL
Be aware that wire bristles
are thrown by the brush
BRUSHING PRESSURE