Maintenance - Makita DHP448 Betriebsanleitung

Installing or removing driver bit or drill bit
(Fig. 11)
Turn the sleeve counterclockwise to open the chuck jaws.
Place the bit in the chuck as far as it will go. Turn the
sleeve clockwise to tighten the chuck. To remove the bit,
turn the sleeve counterclockwise.
Installing bit holder (Fig. 12)
Fit the bit holder into the protrusion at the tool foot on
either right or left side and secure it with a screw.
When not using the driver bit, keep it in the bit holders.
Bits 45 mm long can be kept there.
Adjustable depth rod (Fig. 13)
The adjustable depth rod is used to drill holes of uniform
depth. Loosen the clamp screw, set to desired position,
then tighten the clamp screw.
Hook (Fig. 14)
The hook is convenient for temporarily hanging the tool.
This can be installed on either side of the tool.
To install the hook, insert it into a groove in the tool
housing on either side and then secure it with a screw. To
remove, loosen the screw and then take it out.
OPERATION (Fig. 15)
Hammer drilling operation
CAUTION:
• There is a tremendous and sudden twisting force
exerted on the tool/bit at the time of hole break-
through, when the hole becomes clogged with chips
and particles, or when striking reinforcing rods
embedded in the concrete. Always use the side grip
(auxiliary handle) and firmly hold the tool by both side
grip and switch handle during operations. Failure to do
so may result in the loss of control of the tool and
potentially severe injury.
First, slide the action mode change lever so that it points
to the marking. The adjusting ring can be aligned in any
torque levels for this operation.
Be sure to use a tungsten-carbide tipped bit.
Position the bit at the desired location for the hole, then
pull the switch trigger. Do not force the tool. Light
pressure gives best results. Keep the tool in position and
prevent it from slipping away from the hole.
Do not apply more pressure when the hole becomes
clogged with chips or particles. Instead, run the tool at an
idle, then remove the bit partially from the hole. By
repeating this several times, the hole will be cleaned out
and normal drilling may be resumed.
Blow-out bulb (optional accessory)
(Fig. 16)
After drilling the hole, use the blow-out bulb to clean the
dust out of the hole.
Screwdriving operation
First, slide the action mode change lever so that it points
to the marking. Adjust the adjusting ring to the proper
torque level for your work. Then proceed as follows.
8
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 switch trigger
as soon as the clutch cuts in.
NOTE:
• Make sure that the driver bit is inserted straight in the
screw head, or the screw and/or bit may be damaged.
• When driving wood screw, predrill a pilot hole 2/3 the
diameter of the screw. It makes driving easier and
prevents splitting of the workpiece.
• If the tool is operated continuously until the battery
cartridge has discharged, allow the tool to rest for
15 minutes before proceeding with a fresh battery.
Drilling operation
CAUTION:
• Pressing excessively on the tool will not speed up the
drilling. In fact, this excessive pressure will only serve
to damage the tip of your bit, decrease the tool
performance and shorten the service life of the tool.
• There is a tremendous force exerted on the tool/bit at
the time of hole break through. Hold the tool firmly and
exert care when the bit begins to break through the
workpiece.
• A stuck bit can be removed simply by setting the
reversing switch to reverse rotation in order to back
out. However, the tool may back out abruptly if you do
not hold it firmly.
• Always secure small workpieces in a vise or similar
hold-down device.
• If the tool is operated continuously until the battery
cartridge has discharged, allow the tool to rest for
15 minutes before proceeding with a fresh battery.
First, slide the action mode change lever so that it points
to the marking. The adjusting ring can be aligned in any
torque levels for this operation. Then proceed as follows.
Drilling in wood
When drilling in wood, the best results are obtained with
wood drills equipped with a guide screw. The guide screw
makes drilling easier by pulling the bit into the workpiece.
Drilling in metal
To prevent the bit from slipping when starting a hole,
make an indentation with a center-punch and hammer at
the point to be drilled. Place the point of the bit in the
indentation and start drilling.
Use a cutting lubricant when drilling metals. The
exceptions are iron and brass which should be drilled dry.

MAINTENANCE

CAUTION:
• Always be sure that the tool is switched off and the
battery cartridge is removed before attempting to
perform inspection or maintenance.
• Never use gasoline, benzine, thinner, alcohol or the
like. Discoloration, deformation or cracks may result.
Replacing carbon brushes (Fig. 17)
Replace when they wear down to the limit mark. Keep the
carbon brushes clean and free to slip in the holders. Both
carbon brushes should be replaced at the same time. Use
only identical carbon brushes.