9
GB
CAUTION: If the bit gets stuck, do not try to rock it loose by turning the switch on and off. That is
hazardous and could damage the motor. Rather, unplug the machine and use a wrench on the bit
mounting to work it loose.
CAUTION: Drilling operations are very stressful to the motor and at the end of the cut, the motor
temperature will be very hot, always run the motor at no load for a few minutes until the temperature
returns to a normal range before shutting off.
Then turn off the switch and allow the coasting bit to stop before setting it down.
RESHARPENING A GLAZED BIT
If the bit becomes glazed, resharpen and true it up is by dressing with an appropriate alumina oxide or
silicon carbide dressing stone. Simply drill into the stone as many times as necessary to restore its cutting
performance.
VIBRATION TROUBLESHOOTING
If vibration occurs and it is not caused by embedded steel, stop drilling to find the cause and remedy.
CAUTION: Do not operate with vibration or there will be serious hazard and the diamond core bit
will surely be destroyed.
Vibration is usually caused by:
1.
A bit with too much runout
SOLUTION:
Replace bit.
2.
A bit with diamond segments broken off
SOLUTION:
Repair or replace bit.
MAINTENANCE
Every 50 hours of operation blow compressed air through the motor while running at no load to clean out
accumulated dust.
Always check for a damaged power supply cable, check for loose fasteners and always keep alert for
unusual noises and vibration when operating.
WARNING: Never operate a damaged machine. Always tag a damaged machine and take it out of
service until repairs can be made.
Maintenance which should be performed by an authorized service center, include the following:
•
Replace water seals as needed.
•
Replace the carbon brushes as needed
•
Change the gearbox grease about every 100 hours of operation
•
Replace the clutch discs and spring as needed.
THE CARBON BRUSHES
The carbon brushes are a normal wearing part and must be replaced when they reach their wear limit. This
machine is equipped with auto-stop carbon brushes. If the machine comes to a stop unexpectedly, the brushes
Summary of Contents for DD62
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