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Grains | Abrasive Backings
| Abrasive Terms Dictionary | Technical
TIPS ON STORAGE AND HANDLING of coated abrasives
handling of coated abrasives in the woodworking industry is
sometimes neglectful. Abrasives are often regarded as being
impervious to rain, heat, cold, and rough handling, but this
is not the case.
plants, there is no special room set aside for proper storage
of abrasives. An ideal storage room is one in which all the
walls are inside partitions, rather than against any outside
walls of the building.
should be kept away from windows and any direct heat source.
Air-conditioned rooms are recommended for all users with large
should not be stored on concrete floors or near any area of dampness.
If abrasives are to be stored
for any length of time, it is strongly advised to store them in
the original packing containers or packages. Belts which are already
out of the package should be rolled up and stored on end on a shelf.
Can Cause Many Problems
Relative humidity is an important factor in the transport and storage
of coated abrasives. Optimum conditions are 35% to 50% relative
humidity (45% is ideal) at a temperature range of 60° to 80°F
(70° F is ideal) or 18° to 26° C.
as soon as the relative humidity changes. An example of such a change
is the beginning of the heating season when the humidity in heated
rooms drops by 10% to 15%. The other extreme is after a lengthy
period of rain or foggy weather, when the relative humidity rises
to 80% or more. Coated abrasives are often not given sufficient
time to become equalized to the altered conditions during the transitional
period, and therefore perform less than satisfactorily.
If the relative
humidity increases, so does the moisture content of the backing
and bonding of the coated abrasive.
Productivity and rate of output diminishes. The reduction can be
between 50% to 100% with glue-bonded abrasives, and up to 25% with
backings (paper, cloth, fibre) respond to humidity changes at different
rates than the bonding material (resin or glue). Consequently, the
backing material alters in shape at a different rate than the bonding
material. This difference causes overall distortion in the shape
of the abrasive product. High relative humidity causes the coated
abrasive to curl in a concave manner (grit side up). Low relative
humidity causes the products to curl in a convex manner.
Additionally, damp air can cause the backing- to become "flabby,"
which in turn causes creasing, loading, and
premature grit loss (particularly glue-bonded products). Low humidity
can cause product brittleness and lack of
Belt Handling Prior to Use
Abrasive belts, particularly wide belts, should be removed from
the original packaging at least 24 hours prior to being used. The
belts should be hung on special conditioning racks (easily fabricated)
near the machine on which they will be run. This period will ensure
that the belts have adjusted to ambient temperature and humidity
conditions, as well as removing any "set" in the material
from packaging. For wide belts, this conditioning is crucial.
A proper wide belt conditioning rack should have level hangers of
at least 4" in diameter; preferably non-metallic, and at least
4" from the wall. The wide belts should hang so that they do
not touch each other and are at least 1 foot off of the floor.
For Belt Rack Construction- Coated Abrasive Safety Guidelines
- Eye protection
should always be worn when using any machinery-operated abrasive
product (A.N.S.I. Standard Z87.1). Body protection should also
be worn whenever appropriate; arm guards, leather gloves, and
aprons. Loose clothing, jewelry, and hair should always be secured
before using any powered machinery .
should always be maintained in good working order. Proper electrical
controls should be easily reached and in good working order. Safety
guards on machines should never be removed. Machinery should be
disconnected from the power source before making any abrasive
or machine adjustments.
- Proper dust
control is essential. Always observe OSHA regulations regarding
dust collection. Dust masks are recommended to minimize dust inhalation.
Dust collection systems should be properly maintained, and cleaned
- Never use
a coated abrasive product which is cut, creased, or otherwise
damaged. Observe proper storage conditions.
- Proper machinery
run lap joint belt in proper direction.
- Jog the
machine to start abrasive belt tracking, rather than full-power
- If unusual
ticking or bumping noises are heard on a running abrasive
belt, check belt and machine for possible damage.
- On offhand
applications, present the workpiece to the abrasive belt belo~
the center line of a contact wheel.
belt tension should always be maintained.
tracking should be properly adjusted.