Here we see an original motor, and a stage 1 modified motor that has
been assembled using the coupling nuts.
The cast aluminum mounting plate on the left is usable for combat,
but the machined 6061 plate on the right is substantially stronger.
without the brake assembly
installed. The brush housing,
however, is still designed for this
brake assembly, making it physically
larger than is needed for combat.
So, the first action needed is to
shorten this housing.
The brush housing has a plastic
cover over the end — some older
versions had a metal cover. In either
case, this cover needs to be removed
and discarded. Remove the four
brushes from the housing, and then
remove the four small nuts holding
the brush housing to the back of the
motor. The brush housing should be
able to be pulled straight off the
back of the motor at this time. Be
careful not to pull the armature and
magnet can from the mounting
As you can see in the photos,
there is about an inch of brush
housing that is not needed. You can
cut this off in several different ways.
I have used band saws, jigsaws, a
hacksaw, and even a chop saw
once. By far, the best method has
been with a lathe. Whatever you do,
make sure you do not cut into any
of the machined area in the bottom
of the cavity, and try to make the
edge of the cut as smooth as
possible. This is just a cast piece and
To assemble a stage 2 setup, you will need to
disassemble the motor completely and
reassemble using the heavier duty mounting
plate. You can see the protective sleeve over
one of the studs that is used to protect the
wire leads from chaffing on the stud.
it can crack under strain, so it is best
not to give any potential stress
I usually leave about an 1/8” of
an inch overhang when done. This is
enough to add some strength to
the edge of the brush housing, but
short enough to make mounting
easier in the robot. Make sure all
debris has been removed from
This is the output shaft of the motor.
Removing the seven socket head screws will
allow you to remove the gear assembly
from the mounting plate.
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