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M1051 6" Bench Grinder
OPERATIONS
Changing Grinding Wheels
Before installing any grinding wheel, check it for
integrity by performing a “ring test.” Hang on a string,
then lightly tap the rim of the wheel with a piece of
wood such as the handle of a hammer. The wheel should
have a ringing or harmonic type of sound. If the wheel
responds with a dull thud it may indicate that the wheel
has cracks. Do not use a wheel which is suspected of
having cracks, or if there are visual chips, nicks or dents
in the wheel surface. These discontinuities can lead to
wheel failure causing the wheel to fly apart at operating
speed.
Do not use a wheel that is is suspected of having cracks,
or if there are visual chips, nicks or dents in the wheel
surface. These discontinuities can lead to wheel failure
where the wheel flies apart at operating speed. Always
be sure to use a wheel which is rated for operating at
speeds equal to or greater than 3450 RPM.
To change a grinding wheel, do these step:
1. DISCONNECT THE GRINDER FROM POWER!
2. Disassemble grinder to the level shown in Figure 7.
3. Use a 3⁄4" or 19mm open end wrench on the nut
which holds the wheel on the arbor. Hold the wheel
from turning with the other hand.
Note: The arbor shaft and nut on the left hand side
of the grinder is a left hand thread, so loosening it
will require turning it clockwise.
4. Install the new wheel in the order shown in Figure
8. and tighten the arbor nut snugly, but do not over
tighten or you will crack the wheel.
5. Run a new wheel for at least 1-2 minutes while
standing clear of the line of rotation. If a wheel
does have defects it will generally fail as soon as it
gets up to full speed.
Figure 8. Grinding wheel arrangement.
Figure 7. Grinding wheel access.
NEVER assemble a grinding wheel on
the arbor without paper or fiber discs
between the wheel and the flange.
Omitting the discs can put uneven
stress on the wheel causing it to crack
and possibly fly apart. ALWAYS “ring
test” a wheel before assembly to make
certain it has no cracks or flaws.