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3. Additional Health & Safety Guidance for
Bench Grinders
Safe Operation
• The bench grinder should be level and stable at all times
• Never attempt to lift the grinder while the wheels are in motion –
the centrifugal force created by the rotating stones can cause the
machine to be unstable and could cause serious personal injury.
2. Familiarise yourself with the machine
• Machining operations using bench grinders or grinding wheels
have a history of serious accidents. Most serious accidents are
caused by breakage of the grinding wheel due to damage, poor
maintenance or incorrect mounting of the stone. Other accidents
involve contact with the grinding wheel whilst running and sparks
or waste material being thrown from the grinder.
• The risk of breakage is inherent in every abrasive wheel. Always
handle grinding wheels with extreme care. They are brittle and the
slightest impact can cause fractures within the stone.
• This machine is designed for the grinding and sharpening of tools
and general purpose grinding of objects made from metal or alloy.
Do not attempt to grind items made from any other material.
3. Before switching the machine ‘ON’
• Check that the tool rests and spark guards are correctly adjusted
for the grinding application being undertaken and that the fixings
are secure. The spark guards and tool rests need to be close to
the grinding wheel and will need regular adjustment as the wheel
wears. The gap between the tool rest and grinding wheel should
never be more than 1.5 mm.
• Visually check the grinding wheel for signs of damage or excessive
wear. Check that the outer diameter of the wheel is greater than
the minimum recommended diameters detailed in the manual.
Replace any defective grinding wheels immediately.
• When fitting a new grinding wheel, it should first be inspected to
ensure that it is not cracked or damaged. The new wheel should
first be unpacked and cleaned with a brush and inspected for any
obvious signs of damage. It should then be suspended from the
central hole on a suitable dowel and gently tapped with a light,
non-metallic object. If the wheel sounds dull, it may be cracked and
should not be used. This test cannot be performed with the wheel
already mounted on the machine.
• When fitting the grinding wheel to the machine, always ensure the
clamping flanges are clean and free of any foreign bodies.
• When fitting any grinding wheel, ensure that there is a cardboard
washer (known as a blotter) between each of the clamping flanges
and the surface of the wheel. Never mount a wheel without the
cardboard washers being in place. Replacement washers can be
obtained by contacting our customer service department.
• Before fitting a replacement wheel, always check that it is the
correct diameter and thickness to suit the machine and that the
maximum speed rating on the wheel is higher than the maximum
speed of the machine as detailed in the manual. Never attempt to
modify a wheel to make it fit your machine.
• The bench grinder is only designed to accept grinding wheels of
the correct size to fit inside the wheel housing of the machine. Do
not fit other accessories such as polishing mops, wire wheels etc.
that will not fit inside the wheel housing. Never use the machine
without the wheel housing in place.
• Take care not to over tighten the locking nut to secure the grinding
wheel. Over tightening the nut will cause uneven stress on the
centre of the wheel and may cause it to crack.
• Never attempt to mount a grinding wheel without the original
clamping flanges in place, or if the flanges are damaged.
4. Whilst grinding
• Never stand directly in line with the grinding wheels when first
starting the machine. Stand with your head and body to one side of
the machine.
• Never grind on a new or cold wheel. Always let the machine run
up to speed and run for a minute before applying work to it. If the
machine vibrates excessively, switch the machine ‘OFF’ immediately.
Do not use the machine until the cause of the vibration has been
identified and rectified.
• Do not grind on the side of the wheel.
• Be aware that hot sparks can be a source of ignition. Never carry
out grinding operations near flammable material or in an explosive
environment (gas, liquid, vapors, dust etc).
• The work piece will become extremely hot after a very short
period of contact with the grinding wheel. The work piece should
be quenched regularly to prevent over heating. Do not touch the
machined face of the work piece until your are sure that it has
cooled sufficiently.
• Never apply coolant of any kind directly to the grinding wheel as it
may adversely affect the bonding of the stone.
• The dust from abrasive wheels can be an irritant and a hazard to
your health. Always use the machine in a well ventilated area and
use additional respiratory protective equipment. Clean the machine
regularly with a vacuum cleaner to remove waste material.
• Ensure that the work piece is applied to the tool rest before it is
fed in to the grinding wheel. Unsupported work can catch on the
grinding wheel and may be thrown from your hands.
• When grinding small work pieces, the use of jigs or fixtures to hold
the work piece is recommended. Never try to machine an item that
is too small to hold safely by hand.
• When switching the machine ‘OFF’ allow the stone to slow down
naturally. Do not apply pressure to the stone in order to slow the
machine down more quickly. Do not leave the machine until it has
completely stopped.
5. Maintenance:
• The wheel will become glazed and the grinding face will need to be
dressed to maintain efficient performance. Do not dress the side of
the wheel.
• Regular trueing or dressing of the grinding wheels will help reduce
vibration of the machine, improve grinding efficiency and reduce