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The correct use & care of grinding wheels
Always use the correct type of grinding wheel according to the model of grinder
and your intended use. Do not use grinding wheels as a cutting disc.
During normal use, grinding wheels will wear by becoming chipped, worn at the
edges, grooved, out of balance and clogged by foreign material. This can be
rectified by use of the wheel dresser fitted on the top of the grinder. Rest the
cast face of the dresser on the tool rest and bring the wheels into contact with
the wheel (whilst running). Move the dresser backwards & forwards (left and
right) accross the wheel until a fresh, flat, square face is exposed on the wheel.
Sometimes a wheel may be cracked.
Never under any circumstances use
a cracked wheel for grinding as it could ‘explode’ causing serious injury
to the operator.
Wheels can be tested for cracks with the “Ring Test”. This in-
volves hanging a wheel (removed from the grinder) by a piece of string passed
through its centre hole. The wheel can then be tapped with a piece of scrap
wood or similar and if OK the wheel will “ring”. If there is a defect it will sound
as a “thud”. The defect may not be able to be detected by visual inspection. It is
important that a wheel failing the ring test be permanently discarded.
The GARRICK grinders are supplied with general purpose grinding wheels. For
specialised grinding applications, such as carbide grinding, please consult your
local specialist abrasive distributor.
Always grind by using the outer diameter edge of the grinding wheel. Never
grind on the side of the grinding wheel. This can cause the wheel to shatter.
Do not use excessive force on the grinding wheel. If it is not removing material
fast enough, it is either clogged (requiring cleaning with the wheel dresser as
above) or is not coarse enough. Choose the correct grit (coarseness) for the
job.
Always adjust the tool rest as close as possible to the wheel (maximum 3mm
gap) and do not attempt to grind objects that are to small to hold securely. Do
not use the workpiece to slow down the wheel after turning the grinder off.