The first thing you should do is prepare your watch for polishing. To
protect the finish on the watch case while you buff the watch crystal, you
will want to take your polyimide tape and use small pieces about an inch and
a half long to cover the metal around the crystal. Overlap the pieces of
tape to completely cover the metal around the watch crystal and give your
watch the illusion of having a mane.
Once you have covered all the metal, set the watch aside and set up your
buffing system. And remember, before you start up either motor, be sure to
first put on your safety glasses to protect your eyes from flying debris.
If you are working with a polishing motor: Attach your four inch soft
muslin buff to the motor spindle.
If you are working with a flex shaft or other hand held motor: Attach
your one inch muslin buff to
the hand tool of the motor.
Before you can start actually buffing and polishing the crystal, you need
to apply a thin layer of your crystal polishing compound to the spinning
buffing wheel. Start the motor turning and allow the buff to begin
spinning, once it is operating at normal speed, you will apply the compound
to the buff. For the polishing motor it is easiest to bring the
compound to the buff, whereas with the flex shaft it is easiest to bring the
buffing wheel to the compound, unless you are using the hand tool with a
third hand to hold it in place.
Either way, hold the compound and buffing wheel together with medium-light
pressure for approximately two seconds. This should give you a nice and even
coating of compound across the wheel. Try to avoid over applying the compound
to the wheel, too much compound can be just as detrimental and inefficient
as using too little compound.
Next, take your watch with its protective tape mane and hold the crystal
securely in your hand with the crystal facing up. Keep your fingers away
from the edges of the crystal and hold it securely to keep it from slipping
or from injuring yourself while you work.
the crystal against the buffing wheel with light to medium pressure and keep
it moving against the buff so that you don’t over polish one portion of the
crystal. The crystal's top should face directly toward the buff to maintain
existing crystal shaping. However always keep changing the position of
the crystal against the buff to avoid unnecessary wear on the buff and the
crystal. This will also ensure that you can polish each edge of the
crystal equally. You may find it easier to bring the flex shaft's
handheld buff to the crystal and keep the watch case steady.
NOTE: Be aware that if you are working with a curved or domed crystal, you'll
want to be sure to always keep the buff moving against the crystal along the
curve so you can maintain the nice curved edge.
Stop frequently and take the buffing wheel away from the crystal to check
your progress and make sure that you are not over polishing any particular
Then, after you get a feel for how your buff is working with your plastic
crystal, you can increase the pressure between the wheel and the crystal to
work more quickly. However, be careful not to let the crystal overheat
while you work: take breaks whenever the crystal starts to get hot to the
Continue polishing and checking your progress, repeating Steps 3 and
4 until you can no longer see the scratches on the surface of your
Now you can stop your rotary motor and remove the polyimide tape from your
Then, take your soft cleaning cloth and use it to remove any excess
polishing compound from the face of the crystal and any remaining adhesive
from the watch case.
When that is complete, your crystal should look just like new and you can
start wearing it again. For other handy methods for polishing watch
crystals, check out our
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