Makita 6904VH Manual De Instrucciones página 6

– High tensile bolt –
Hold the tool firmly and place the socket over the bolt or nut. Turn the tool on and fasten for the proper fasten-
ing time.
NOTE:
• Hold the tool pointed straight at the bolt or nut without applying excessive pressure on the tool.
• Excessive fastening torque may damage the bolt or nut. Before starting your job, always perform a test oper-
ation to verify the adequate fastening speed and time for your bolt or nut.
The fastening torque is affected by a wide variety of factors including the following. After fastening, always
check the torque with a torque wrench.
1. Voltage
Voltage drop will cause a reduction in the fastening torque.
2. Socket
• Failure to use the correct size socket will cause a reduction in the fastening torque.
• A worn socket (wear on the hex end or square end) will cause a reduction in the fastening torque.
3. Bolt
• Even though the torque coefficient and the class of bolt are the same, the proper fastening torque will
differ according to the diameter of the bolt.
• Even though the diameters of bolts are the same, the proper fastening torque will differ according to the
torque coefficient, the class of bolt and the bolt length.
4. The use of the universal joint or the extension bar somewhat reduces the fastening force of the impact
wrench. Compensate by fastening for a longer period of time.
5. The type of materials to be fastened and the manner of holding the tool will affect the torque.
Screwdriving (Fig. 6)
For 6904VH only
When driving screws, install a bit adapter (optional
accessory) on the tool and insert a driver bit (optional
accessory) into the bit adapter. Place the point of the
driver bit in the screw head and apply pressure to the
tool. Start the tool slowly and then increase the
speed gradually. Release the trigger just as the screw
bottoms out.
NOTE:
• Use the best size driver bit for the size of screw that
you wish to use.
• Hold the tool pointed straight at the screw, or the
screw and/or bit may be damaged.
6
Fastening time
Proper fastening torque for M16
Proper fastening torque for M12
Seconds
• When driving wood screws, pridrill pilot holes to
make driving easier and to prevent splitting of the
workpiece. The pilot holes should be slightly
smaller than the wood screws in diameter.
MAINTENANCE
CAUTION:
Always be sure that the tool is switched off and
unplugged before carrying out any work on the tool.
To maintain product safety and reliability, repairs,
maintenance or adjustment should be carried out by
a Makita Authorized Service Center.