Makita IMPACT WRENCH 6904VH Instruction Manual page 9

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 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 some-
what reduces the fastening force of the impact wrench.
Compensate by fastening for a longer period of time.
5. The manner of holding the tool or the material of driving
position to be fastened will affect the torque.
Screwdriving operation
When driving screws, install a bit adapter (optional acces-
002371
sory) on the tool and insert a driver bit (optional accessory)
into the bit adapter.
Hold the tool firmly and place the point of the driver bit in the
screw head. Apply forward pressure to the tool to the extent
that the bit will not slip off the screw. Start the tool slowly and
then increase the speed gradually. Release the switch trigger
just as the screw bottoms out.
NOTE:
• Use the proper bit for the head of the screw/bolt that you
wish to use.
• Hold the tool pointed straight at the screw or the screw
and/or bit may be damaged.
• When driving wood screws, predrill 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.
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