Carbon Brushes; Maintenance Information - Dremel 4200 Operating/Safety Instructions Manual

DM 2610029872 01-13_DM 2610029872 01-13.qxp 1/7/13 10:43 AM Page 13
Preventive maintenance
WARNING
performed by unauthorized
personnel may result in misplacing of
internal wires and components which could
cause serious hazard. We recommend that
all tool service be performed by a Dremel
Service Facility.
To
WARNING
unexpected starting or
electrical shock, always remove plug from
wall outlet before performing service or
cleaning.

CARBON BRUSHES

The brushes and commutator in your tool have
been engineered for many hours of
dependable service.
In order to prepare your brushes for use, run
your tool at full speed for 5 minutes under no
load. This will properly "seat" your brushes,
which extends the life of both your brushes
and your tool.
To maintain peak efficiency of the motor, we
recommend every 40 - 50 hours the brushes
be examined. Only genuine Dremel replace-
ment brushes specially designed for your tool
should be used.
MAINTENANCE OF REPLACEABLE
BRUSHES ON MODEL 4200
The brushes should be inspected frequently
when tools are used continuously. If your tool
runs sporadically, loses power, makes unusual
noises or runs at a reduced speed, check the
brushes.
To continue using the tool
CAUTION
in
permanently damage your tool.
Follow these steps to check/change the rotary
tool brushes:
1. With the power cord unplugged, place the
tool on a clean surface. Use a screwdriver to
remove the brush caps in a counter-clockwise
direction (Figure 9).
2. Remove the brushes from the tool by
pulling on the spring that is attached to the
carbon brush. If the brush is less than 1/8"
long and the end surface of the brush that
contacts the commutator is rough and/or
pitted, they should be replaced. Check both
brushes (Figure 10).

Maintenance Information

Service
avoid injury from
this condition
Usually the brushes will not wear out simul-
taneously. If one brush is worn out, replace
both brushes. Make sure the brushes are
installed as illustrated. The curved surface of
the brush must match the curvature of the
commutator. Also check that the brush caps sit
flush with the tool housing.
3. After replacing brushes the tool should be
run at no-load; place it on a clean surface and
run it freely at full speed for 5 minutes before
loading (or using) the tool. This will allow the
brushes to "seat" properly and will give you
more hours of life from each set of brushes.
This will also extend the total life of your tool
since the commutator surface will "wear"
longer.
will
13
FIG. 10
BRUSH CAP
BRUSH SPRING
CURVED END OF
BRUSH MUST
MATCH
CURVATURE OF
BRUSH
COMMUTATOR
FIG. 9