Maintenance - Bosch 1638 Operating/Safety Instructions Manual

BM 2610995759 11/00 11/16/00 11:50 AM
work surface and tilt the tool to an upright
position with the bit entering the scrap
portion of the area being cut. Move the bit to
the line you wish to follow and cut in a
clockwise position. Cutting at a slow even
rate will make following a line easier and will
put less stress on the bit.
Service
Preventive maintenance
WARNING
!
performed by unauth-
orized personnel may result in misplacing
of internal wires and components which
could cause serious
recommend that all tool service be
performed by a Bosch Factory Service
Center or Authorized Bosch Service Station.
TOOL LUBRICATION
Your Bosch tool has been properly
lubricated and is ready to use. It is
recommended that tools with gears be
regreased with a special gear lubricant at
every brush change.
CARBON BRUSHES
The brushes and commutator in your tool
have been engineered for many hours of
dependable service. To maintain peak
efficiency of the motor, we recommend
every two to six months the brushes be
examined. Only genuine Bosch replacement
brushes specially designed for your tool
should be used.
If an extension cord is
WARNING
!
necessary, a cord with
adequate size conductors that is capable
of carrying the current necessary for your
tool must be used. This will prevent
excessive voltage drop, loss of power or
overheating. Grounded tools must use 3-
wire extension cords that have 3-prong
plugs and receptacles.
NOTE: The smaller the gauge number, the
heavier the cord.
Page 8
NOTE: When cutting on a vertical surface,
avoid ending your cut at the bottom of the
hole. If possible, start and end your cut at
the top so the scrap part will not drop onto
the rotating bit. Turn the tool off and remove
it from the cut out hole.

Maintenance

After about 300-400 hours of operation, or at
every second brush change, the bearings
should be replaced at Bosch Factory Service
Center or Authorized Bosch Service Station.
Bearings which become noisy (due to heavy
hazard. We
load or very abrasive material cutting) should
be replaced at once to avoid overheating or
motor failure.
WARNING
!
the power supply before cleaning or
performing any maintenance. The tool may
be cleaned
compressed dry air. Always wear safety
goggles when cleaning tools with
compressed air.
Ventilation openings and switch levers must
be kept clean and free of foreign matter. Do
not attempt to clean by inserting pointed
objects through openings.
CAUTION
!
plastic parts. Some of these are: gasoline,
carbon tetrachloride, chlorinated cleaning
solvents,
detergents that contain ammonia.
Accessories
RECOMMENDED SIZES OF EXTENSION CORDS
120 VOLT ALTERNATING CURRENT TOOLS
Cord Size in A.W.G.
Tool's
Ampere
Cord Length in Feet
Rating
25
3-6 18
6-8 18
8-10 18
10-12
16
12-16 14
-8-
BEARINGS
Cleaning
To avoid accidents always
disconnect the tool from
most effectively with
Certain cleaning agents
and solvents damage
ammonia and household
2
Wire Sizes in mm
Cord Length in Meters
50 100 150 15 30 60 120
16 16 14 .75 .75 1.5 2.5
16 14 12 .75 1.0 2.5 4.0
16 14 12 .75 1.0 2.5 4.0
16 14 12 1.0 2.5 4.0 —
12 — — — — — —