Operating Tips; Drill Bits - Bosch GSR18V-400 Operating/Safety Instructions Manual

Driving Nuts and Bolts
Variable speed control must be used with
caution for driving nuts and bolts with socket
set attach ments. The technique is to start
slowly, increasing speed as the nut or bolt
runs down. Set the nut or bolt snugly by
slowing the drill to a stop. If this procedure
is not followed, the tool will have a tendency
to torque or twist in your hands when the nut
or bolt seats.
Drilling
You will extend the life of your bits and do
neater work if you always put the bit in con-
tact with the work before pulling the trigger.
During the oper a tion, hold the tool firmly and
exert light, steady pressure. Too much pres-
sure at low speed will stall the tool. Too little
pressure will keep the bit from cutting and
cause excess friction by sliding over the sur-
face. This can be damaging to both tool and
bit.
Drilling with Variable Speed
The variable speed trigger allows you to
slowly increase RPM. By using a slow start-
ing speed, you are able to keep the bit from
"wander ing". You can increase the speed as
the bit "bites" into the work by squeezing the
trigger.
Driving with Variable Speed
Variable speed drills will double as a power
screwdriver by using a screwdriver bit. Prior
to driving screws, pilot and clearance holes
should be drilled. Place the threaded end of
the screw in the pilot or clearance hole and
start driving the screw slowly, increasing the
speed as the screw runs down. Set the screw
snugly by slowing to a stop.
Fastening with Screws
The procedure shown in Fig. 11 will enable
you to fasten materials together using your
drill without stripping, splitting or separating
the material.
First, clamp the pieces together and drill the
hole 2/3 the diameter of the screw. If the ma-
terial is soft, drill only 2/3 the proper length.
If it is hard, drill the entire length.
2610067354 GSR18V-400 02-22.indd 14

Operating Tips

FASTENING WITH
SCREWS
1. Drill 2/3 diameter
and 2/3 of screw
length for soft
materials, full length
for hard materials
Screw
Second, unclamp the pieces and drill the
hole in the top piece of wood again to the
same diameter as the shank of the screw.
Third, if flat head screw is used, countersink
the hole to make the screw flush with the sur-
face. Realign the holes on the two pieces and
apply even pressure when driving the screw.
The screw shank clearance hole in the first
piece allows the screw head to pull the piec-
es tightly together.
The adjustable screw drill accessory will do
all of these operations quickly and easily.
Screw drills are available for screw sizes No.
6, 8, 10 and 12.

Drill Bits

Always inspect drill bits for excessive wear.
Use only bits that are sharp and in good con-
dition.
TWIST BITS: Available with straight and re-
duced shanks for wood and light duty metal
drilling. High speed bits cut faster and last
longer on hard ma terials.
CARBIDE TIPPED BITS: Used for drilling
stone, con crete, plaster, cement and other
unusually hard nonmetals. Use continuous
heavy feed pres sure when employing carbide
tip bits.
-14-
2. Drill same
diameter as
screw shank
3. Countersink
same diameter
as screw head
Apply a slight
even pressure
when driving
screws
Fig. 11
Adjustable
Screw
Drill
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2/17/22 1:19 PM