DeWalt DW138 Instruction Manual page 7

DW138/DW139/384347-01 rev
4.Always apply pressure in a straight line with the bit. Use enough
pressure to keep the drill bit biting, but do not push hard enough to
stall the motor or deflect the bit.
5.Hold tool firmly to control the twisting action of the drill.
6.IF DRILL STALLS, it is usually because it is being overloaded.
RELEASE TRIGGER IMMEDIATELY, remove drill bit from work,
and determine cause of stalling. DO NOT CLICK TRIGGER ON
AND OFF IN AN ATTEMPT TO START A STALLED DRILL – THIS
CAN DAMAGE THE DRILL.
7.To minimize stalling on breaking through the material, reduce
pressure on drill and ease the bit through the last fractional part of
the hole.
8.Keep the motor running when pulling the bit back out of a drilled
hole. This will help prevent jamming.
Drilling in Wood
Holes in wood can be made with the same twist drills used for metal.
These bits may overheat unless pulled out frequently to clear chips
from the flutes. For larger holes, use spade bits, power auger bits, or
hole saws. Work that is likely to splinter should be backed up with a
block of wood.
Drilling in Metals
Use a cutting lubricant when drilling metals. The exceptions are cast
iron and brass which should be drilled dry. The cutting lubricants that
work best are sulphurised cutting oil or lard oil; bacon grease will also
serve the purpose.
Drilling in Masonry
Use carbide tipped masonry bits at low speeds. Keep even force on the
drill but not so much that you crack the brittle materials. A smooth, even
flow of dust indicates the proper drilling rate.
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Lubrication
All bearings used are factory lubricated to last the life of the tool. All
needle bearings used receive their lubrication from the grease in the
gear case. Clean and relubricate gear case yearly or whenever
servicing requires the gear case to be removed. Use type and quantity
of grease shown on Parts Bulletin packed with your tool.
Gear case is removed by removing the three screws from the front of
the tool. If the chuck is too large to permit removal of the two top
screws, see instructions for chuck removal.
Motor Brushes
TURN OFF TOOL AND DISCONNECT FROM POWER SUPPLY.
To inspect brushes, unscrew the plastic brush inspection caps (located
in the sides of the motor housing) and the spring and brush assemblies
may be withdrawn from the tool. Keep brushes clean and sliding freely
in their guides. Carbon brushes have varying symbols stamped into
them, and if the brush is worn down to a point where the symbol is not
visible, they must be replaced. New brush assemblies are available at
authorized service centers.
Accessories
Recommended accessories for use with your tool are available at extra
cost from your local dealer or authorized service center.
If you need assistance in locating any accessory, please contact
D WALT Industrial Tool Co., 701 East Joppa Road, Baltimore, MD
E
21286 or call 1-800-433-9258.
CAUTION: The use of any other accessory not recommended for
use with this tool could be hazardous.
For safety in use, the following accessories should be used only in
sizes up to the maximums shown in the table below.
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