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If you are having three driven axles,
remove the drive unit from the subframe
and clip the third axle into place. Replace
the drive unit in the subframe, now
engaging all six of the bearing carriers into
their slots.
Holding the 'four-wheeled' part of the
drive unit such that the tops of all four
of its bearing carriers are level with the top
of the subframe sides, check that the third
axle has at least ±0.5mm of vertical travel.
If this is not the case, check for free
movement of the individual carriers in
t heir slots and then, if required, open out
the Bachmann bearings a little more, on this
axle only, up to a maximum of 2.3mm.
That concludes the test. Unclip the
axles from the Drive Unit and store them
in their respective containers.
We now use one of the inner or outer axles, still with its bearing carriers fitted,
to check for lateral play. If you are using ready assembled wheelsets and have
one wheel already fitted to each axle, you will need to vary the operations slightly to
suit.
Fit the wheels to the axle to the correct back-to-back measurement. Test fit the
axle in the bogie subframe to determine the amount of lateral play. There should be
just a little; enough to allow the wheelset to tilt such that the wheel on one side is
raised about 1mm with respect to that on the other. If necessary, dismantle the
wheelset and fit full- and half-width 2mm washers (supplied on the fret) between the
bearing carriers and wheels, until this condition is met. If there is insufficient play,
even with no washers fitted, reduce the inner width of the wheel bosses accordingly.
Record the washer configuration you arrived at and dismantle the wheelset. If you
had to reduce the inner wheel bosses, repeat the operation on the remaining
wheels. Take off an extra 0.5mm on the wheels for the two centre axles, subject to
not going beyond the line of the inner wheel rim.
Now we can fit the Bachmann gears to the new axles and assemble the
wheelsets. Do the following for each axle.
If you have one wheel already fitted to the axle, slide on the required number of
washers adjacent to that wheel, then the bearing carrier (ears facing the wheel),
then a Bachmann drive bearing.
Fitting Wheelsets
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04/05/2017