Tool Tips - Bosch GEX34-6 Operating/Safety Instructions Manual

Selecting Sanding Discs
Open-coat aluminum oxide sanding discs
are recommended for most wood or metal
sanding applications, as this synthetic
material cuts quickly and wears well. Some
applications, such as plastics, glass, or
stone require silicon carbide discs, which
have a very sharp cutting edge. For best
results, use Bosch sanding and polishing
accessories, which are of superior quality
and are carefully selected to produce
professional quality results with your
sander.
An alternative to standard sanding discs is
to use a SandNet™ connection pad and
SandNet™ mesh sanding discs.
Start of Sanding
With the workpiece firmly secured, first
place the sander's pad on the work surface,
then switch the tool on.
DO NOT start the tool and bring it up to
speed before applying to the work
DO NOT apply excessive pressure when
switch the tool on (or at any other time)
Either method will likely create swirl marks.
Applying excessive pressure upon start-up
will also shorten the life of the switch.
Sanding Action
This sander has optimized random sanding
action. The pad orbits and rotates freely,
duplicating natural hand sanding action for
aggressive stock removal and smooth, well-
blended surface finish. The orbit offset for
this tool is 2 mm (5/64")
In general, higher speeds will give the best
results. If faster removal is desired, DO
NOT APPLY PRESSURE ON THE TOOL; use a
coarser grade of abrasive. Move the sander
in long sweeping strokes, parallel to the
grain using some lateral motion to overlap
the strokes by as much as 75%.
random orbit action allows cross-grain
sanding, but be careful not to tilt the sander
near edges, or undesirable rounding may
result.
Sanding Sequence
If the surface is rough, begin with coarser
grits and then complete the surfacing with

Tool Tips

medium and fine abrasives. Because the
random orbit action is so effective, it is
often possible to begin sanding with a
medium grit disc and go directly to fine
finishing. To avoid uneven results, do not
skip more than one grit size when going
from coarser to finer, and do not sand in
one area for too long.
Removal of Sander
To help prevent swirl marks when the job is
completed, gently lift the tool from the work
surface, then switch the tool off.
Operating in this manner will also prolong
the switch life.
Polishing
For most polishing, the extra-soft backing
pad will give the best results. The random
orbit sander may be fitted with an optional
foam buffing pad or polishing bonnet to
polish or remove scratches from painted or
finished surfaces, plastics, and even glass.
The tool is operated in much the same way
as when sanding, but the following points
should be observed;
Apply the compound to the surface, and use
the sponge applicator pad with light
pressure and a circular motion to remove
scratches and restore weathered finishes.
Use only as much compound as necessary,
and clean the sponge frequently during use.
When initial polishing is completed, wipe
away any excess compound with a soft
towel, and then polish the surface to its
final finish with the polishing bonnet. Use
smooth overlapping strokes for best results.
It is important to note that the orbit speed
of the random orbit sander is not the same
as the RPM of a standard right-angle
polisher. The random orbit action is much
like a powerful hand polishing action, and
therefore does not have the high speeds at
the edge of the pad which can burn the
The
work surface. For this reason, it is possible
to select a higher OPM for the random orbit
sander than the recommended RPM for a
standard polisher. Practice on a hidden
area or test surface until you have
determined the tool is suitable for your
polishing application.
Clean the buffing pad and polishing bonnet
with mild detergents and warm water. DO
NOT use solvents.
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