16
Low voltage cut out
The battery pack used on this tool is fitted with a
low
voltage cut out
feature within the circuitry.
The
low voltage cut out
feature operates when the voltage
drops below a pre-set value. This feature automatically
stops the wrench from operating (similar to that of the
overload condition). When this condition occurs you will
need to either insert another battery into the wrench or
recharge the existing battery.
The
low voltage cut out
feature has been added to
maximise the tool’s life. When this occurs, recharge the
battery pack by following the battery charging section in
this manual.
Note:
Attempting to restart the tool without either recharging
the battery or installing another battery (with charge) will
lead to the wrench restarting and then stopping again after
only a few seconds of operation.
Operating tips
You will extend the life of your bits and do neater work if you
always put the bit in contact with the work before pulling the
trigger. During the operation, hold the tool firmly and exert
light, steady pressure. Too much pressure at low speed will
stall the tool. Too little pressure will allow the driver bit to
disengage from the fastener and damage the fastener head
and driver bit.
Always use a good quality driver bit which matches
the screw head correctly. When using a flat driver bit
ensure a correct fit between the fastener and bit and it is
recommended to use a bit with a sleeved guide.
Driving with variable speed
The technique is to start slowly, increasing the speed as
the screw runs down. Set the screw snugly by slowing to a
stop, or allowing the impacts to set the screw to the desired
torque over a period of impact time. Prior to driving screws,
pilot and clearance holes should be drilled. Always hold the
machine straight on the bolt to be tightened.
The best method to determine the right impacting/tightening
duration is by means of a trial. For small screws, the right
impacting/tightening duration can be reached in less then
0.5 Sec. Therefore, work with low RPM and switch the
machine off immediately when the screw is tight and the
impacting sound can be heard.
For screwing larger, longer wood screws into hard material,
pre-drilling is the best method.
Tightening torque
The tightening torque depends on the duration of the
impacting/tightening action. The largest tightening torque
is achieved after approx. 6 to 10 Sec. impacting/tightening
action. Over tightening or the use of poor quality fasteners
can result in the fastener shearing.
The torque build-up depends on the following factors:
•
Hardness of the bolts/nuts.
•
Type of washer (disk washer, spring washer, seal).
•
Hardness of the material to be joined.
•
Lubricating effect at the surfaces of the junction.
This leads to the following application cases:
Hard case:
The joining of metal to metal with a disk
washer. The maximum torque is reached
after a relative short impacting/tightening
action.
Medium case:
The joining of metal to metal where spring
ring washer, disk spring washer, stud bolts
or bolts/nuts with conical seats are used.
Soft case:
The joining of e.g. metal to wood or
insulation material.
For middle or soft joining cases, the maximum tightening
torque is less as for hard cases. Therefore, a longer
impacting/tightening action is necessary to arrive at the
maximum tightening torque.
Fastening with screws
This procedure will enable you to fasten materials together
with your tool without stripping, splitting or separating the
material.