Grinding Wheels - Metabo DS 125 W Operating Instructions Manual

Prior to Commissioning
The mains voltage must correspond with the voltage
stated on the machine's name plate.
The grinding wheels are to be subjected to a resonance
test (see section Grinding Wheel Check below). This
resonance test is also to be carried out when replacement
grinding wheels are mounted.
The grinder is to be subjected to a no-load trial run for at
least 5 minutes. Do not stand in the grinder's danger
zone during this trial run.
Commissioning
This double bench grinder is used for rough grinding.
Please note that it is not intended for continuous operation.
To prevent possible overloading/overheating it should
not be operated for more than 15 - 30 minutes at a time.
Let grinder cool down before operating again.
Apply moderate pressure when holding the workpiece
against the grinding wheel. Remember that the metal
heats up by the grinding. The workpiece should therefore
regularly cooled by submerging it in cold water.
The dry grinding wheels of this bench grinders are
suitable for rough grinding only.
Size of part to be machined
The part to be machined must at least be large enough
to hold securely in both hands.
A larger work piece must also be able to be held securely
in and must not slip from the work piece support during
the grinding process. When selecting the size of the work
pieces, please bear in mind the grinding capacity of your
grinding machine.
Drill grinding
The work piece support on the right grinding wheel is
fitted with a trough for drill grinding.
After switching on the double grinding machine hold the
drill to be ground with both hands and push it into the
trough. Then carefully guide the tip of the drill towards
the grinding wheel and slowly turn the drill throughout
the entire grinding process.
Selecting a suitable Grinding Wheel
This double bench grinder is factory fitted with two
different normal corundum grinding wheels. On one side
a wheel with a coarse grit is mounted, on the other side
a fine grit grinding wheel. As a rule, the bulk of the arising
grinding works such as the grinding of various axes, drill
bits and screw drivers can be accomplished with this
grinding wheel. For other jobs, especially the sharpening
of knifes as well as the machining of hardened steel, a
suitable grinding wheel according to the table on page 9
should be selected. Please keep in mind that there is no
grinding wheel type suitable for all different requirements
and the choice of the right grinding wheel is critical for the
result of your work.

Grinding Wheels

When replacing grinding wheels it is important to ensure
that the new wheel fits your grinding machine (see fig.
5), i.e. arbor bore size, outer diameter and wheel width
must correspond with the original grinding wheel. This
information is shown on all commercially available
grinding wheels. It is recommended to check if an
approval code is shown on the grinding wheel and to
buy only approved grinding wheels. Metabo genuine
grinding wheels are guaranteed for a constant high
quality level. They are available at your metabo dealer
in all common sizes and compositions.
5
1 Manufacturer's address or stamp
2 Permissible speed in r.p.m.
3 Nominal size
4 Material (coded)
5 Test mark
6 Maximum working speed in m/s
Grinding Wheel Check
Before a new grinding wheel is mounted it should be
subjected to a visual inspection and a resonance test,
to detect any possible defects or cracks. For the reso-
nance test, let the wheel hang from a piece of string and
tap lightly with a screwdriver handle or similar (no metal!).
If the sound is not clear, but rather dull and hollow the
wheel is likely to be damaged and should not be used.
6
The grinding wheel should slide onto the arbor easily.
Forcing it on the arbor, e.g. by striking with a hammer,
may break the wheel and is not permissible for safety
reasons. For the same reason the drilling out of too small
an arbor bore is not permitted.
After the new wheel is mounted it should be left running
idle for at least 5 minutes. Screen off workplace to pre-
vent damage in case the wheel breaks and stay out of
the danger zone.
9