TM 5-3805-281-10
e) If vibrations start to occur after the hammer has been operative for some time, this
means that the carrier downward pressure has not followed the tool penetration. You
must maintain a constant pressure from the carrier on the hammer, as the hammer is
penetrating the work.
f) An INDECO hammer senses the strength and density of the surface being broken, and
adjusts hammer impact power accordingly. The operator will be able to hear the
difference in the blows when a rock is broken or not broken. The hammer rhythm will
be fast and sharp if the material is frail and flaky; slow and powerful if the rock is
compact and uniform. Impact speed will also be slower the deeper the hammer pen-
etrates.
g) As soon as cracks start to appear in the material being worked on, and the tool
starts to appear from the bushing, stop the hammer at once. Do not raise the hammer
from the material until it has stopped completely.
h) If cracks in the material do not appear in 30 seconds, move to a new position along
the grain of the material, perhaps working on a smaller section or edge of the mate-
rial. Always look for advantageous weak points in the material (e.g. cracks, bumps,
veins) at which to start. This saves undue stress on the breaker.
i) In a quarry, or when breaking oversized rocks, position the material to be broken on a
hard base to minimize vibrations of the material.
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