Makita 6953 - Manual (Page 8)

8
OPERATION The proper fastening torque may differ depending upon the
kind or size of the bolt. The relation between fastening torque
and fastening time is shown in the figures.
OPERATION
Hold the tool firmly and place the socket over the bolt or nut.
Turn the tool on and fasten for the proper fastening time.
NOTE:
• When fastening screw M8 (5/16”) or smaller, carefully
adjust pressure on the switch trigger so that the screw is
not damaged.
• Hold the tool pointed straight at the bolt or nut without
applying excessive pressure on the tool.
• If you fasten the bolt for a time longer than shown in the
figures, the bolt or the socket may be overstressed,
damaged, etc. Before starting your job, always perform a
test operation to determine the proper fastening time for
your bolt. Especially for the bolt over than M8 (5/16”),
perform the above test operation to prevent the trouble
on socket or bolt, etc.
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. 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.
2. 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.
3. The manner of holding the tool or the material of driving
position to be fastened will affect the torque.
4. Operating the tool at low speed will cause a reduction in
the fastening torque.
001658
M14 (9/16”)
1
80
(58)
60
(43)
40
(29)
20
(14)
0
2 3
N·m
(ft·lbs)
M14 (9/16”)
M12 (1/2”)
100
(72)
120
(86)
140
(100)
M16 (5/8”)
M16 (5/8”)
M12 (1/2”)
Fastening time
Fastening
torque
Seconds
Standard bolt
001659
M10 (3/8”)
1
80
(58)
60
(43)
40
(29)
20
(14)
0
2 3
N·m
(ft·lbs)
M10 (3/8”)
M8 (5/16”)
100
(72)
120
(86)
140
(100)
M12 (1/2”)
M12 (1/2”)
M8 (5/16”)
Fastening time
Fastening
torque
Seconds
High tensile bolt