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ENGLISH
7.2
SIGNPOSTING OF THE DRILLING AREA
Before drilling walls or floors, make sure the stick that comes off the hole does not cause any damage.
Therefore, signpost the area of work with danger signals. If the stick is likely to cause any damage, install a structure
or a support to collect it when the drill is finished.
When the material that is going to be perforated is not part of a large construction, make sure this is well
anchored or securely attached.
7.3
TYPES OF CROWNS
Use the appropriate crown for the material to drill. Using a crown in poor condition with worn out segments or
inappropriate for the material to drill can lead to large motor overload and premature wear of the drilling unit.
After using the crown repeatedly to drill very hard materials or hard concrete with steel reinforcements, it is
advisable to sharpen the segments by dry boring three or four 2 cm deep holes in an abrasive material.
WARNING: Do not hold ever with hands the abrasive materials to revive the crown.
7.4
MOUNTING THE CROWNS
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Always Place a bronze washer between the axis carrying the crowns and the 1”1/4 UNC crown.
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Greasing the thread of the crown will avoid the oxidation and make it easier to extract the
crown.
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If the connection of the crown is not the same as that of the axis, use a ½ G 1 1/4 UNC adapter
that are available as accessories.
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Before starting to drill, make sure the crown is well adjusted in the axis.
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Before removing the crown, unplug the machine off the electricity.
7.5
SELECTION OF THE ROTATION SPEED
The advised crown revolutions are in function of the crown diameter, hardness and consistency of the
materials to drill and diameter of the concrete reinforcements to drill through. Reduce the speed of drilling when you
have to go through concrete armature with steel bars. Once crossed, you can go back to normal speed.
To select a speed, do it with the engine completely stopped, do not use tweezers, pliers or other type of tools.
To select the speed, do it with your fingers. At the time you select the speed, turn with the other hand the axis to
facilitate the alignment of the gears. In some models, you can only give a half turn 180.)
Note the following table to select properly the drilling speed.
