Jet IBGB-248VS, Operating Instructions And Parts Manual

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9.2 Precautions
9.2.1 Wheel grinding
1. Before starting grinder, turn grinding wheel by
hand to verify that it is clear of obstruction and
turns freely. The tool rest and spark guard
should not touch the wheel.
2. Keep tool rest and spark guard to within 1/16"
of grinding wheel.
3. Turn on grinder and allow it to reach full running
speed before starting to grind.
4. Adjust the eye shield as needed.
5. Keep a steady, moderate pressure on the
workpiece and keep it moving at an even pace
for smooth grinding. Pressing too hard
overheats the motor and prematurely wears the
grinding wheel. Note the original bevel angle on
the item to be sharpened and try to maintain the
same shape. The grinding wheel should rotate
into the object being sharpened.
6. If grinding a narrow workpiece, slide it laterally
across width of wheel. Using full width of wheel
will help prevent a groove from forming at one
place on the wheel.
7. Keep a water pot filled with water and dip your
work into it regularly to prevent overheating.
Overheating can weaken metals. Do not apply
water directly to grinding wheel.
8. Do not use the side of the grinding wheel; this
puts dangerous stress on the wheel.
9. When wheel becomes loaded or dull, use an
approved grinding wheel dresser and dress the
wheel face.
10. At all times, keep hands and fingers away from
pinch points.
9.2.2 Belt sanding
1. Move belt by hand to ensure that wheels rotate
freely without obstruction, table or tool rest does
not contact belt, and belt tracks properly.
2. Use the entire width of the belt to reduce wear
in one place.
3. At all times, keep hands and fingers away from
pinch points.
10.0 User-maintenance
For safety, turn switch to OFF and remove plug from
power source outlet before performing maintenance
on the grinder/sander.
If the power cord is worn, cut or damaged in any
way, have it replaced immediately.
10.1 Installing/replacing sanding belt
1. Disconnect grinder/sander from power source.
2. Unscrew knobs and open side guard.
3. Pull tension lever (D, Figure 10-1) outward to
compress spring and de-tension belt.
4. Remove old belt by sliding it off wheels. Install
new belt, centering it on the wheels. Make sure
arrow printed on back of sanding belt matches
direction of belt movement.
5. Push lever (D) inward to tension belt.
6. Verify proper belt tracking, sect. 8.5.
7. Close side cover and secure with knobs before
operating.
Figure 10-1: installing sanding belt
10.2 Care of grinding wheels
In normal use, grinding wheels may become
cracked, grooved, rounded at the edges, chipped,
out of true or loaded with foreign material.
Cracked wheels should be replaced
IMMEDIATELY. The other conditions can be
remedied with a dressing tool. New wheels
sometimes require dressing to make them round.
See
sect. 10.5.
10.3 Ring test
Before replacing a grinding wheel, perform this
simple test on the replacement wheel:
1. Loop a piece of string through the grinding
wheel hole and suspend the wheel by holding
up the string.
2. Tap the wheel with a scrap of wood or wooden
dowel.
3. A good wheel will "ring"; a defective wheel will
"thud". Discard any wheel that does not "ring".
An internal defect may not be apparent by visual
inspection alone. The ring test may identify an
internal crack or void.