Glue the plastic card spacers to the tops of
the bolsters. Clamp them up against the
Pivot Plate, using the M2 screws and all the
other pivot components, as shown in the
diagram above, while the glue sets.
Once the glue has set, mark the projecting
threads of the pivot screws, remove and
shorten them so they project no more than a
thread's turn below the captive nuts.
Lightly coat the top of the bolster with
silicone or multipurpose grease.
Refit the Bolsters to the Subframes.
Refit the Bogies to the chassis block and do up the pivot screws until there is just a
very light preload between the Bolster top and Pivot Plate. You are aiming for a setting
which allows the bogie to swivel freely, but prevents the Bolster from rocking against the
Plate. You may well find that the screws slacken off as the bogies swivel: don't worry
about that for now, in the final assembly they'll be retained by a thread locker.
You can now do static and rolling (pushed or pulled) tests to check ride height, body
clearances, track-holding and suspension behaviour. It's helpful to clear any gremlins
now, before the mechanical drives and detail are fitted. It is also extremely satisfying to
feel how the locomotive moves with its sprung suspension.
You also have the option, at this stage, to do rolling tests with the Drive Units fitted
to the axles (provided that you have not re-fitted the worms into the drives). Remove
the bogies from the loco, and the Bolsters from the Subframes. Carefully place the Drive
Units over the drive bearings on the axles, joggling the bearings into position as required,
then push down on the Drive Units to clip them on to the bearings. Reassemble the loco
and test as before.
You may not need to remove the wheelsets from the subframe at this stage, but,
when you do, the procedure is as follows. Support the subframe on a narrow block as
f o r fitting. Use the screwdriver to press one of the primary springs downwards and
outwards, then lift that side of the end wheelset to bring the spring up on to the outside
of its primary spring seat. Repeat for the other side, then lift the wheelset to slide the
springs up over the outsides of the primary and secondary spring seats. Repeat for the
axle at the other end of the bogie.
Bachmann 66: Springs, Bogie Assembly and Rolling Test
46/60
(c) PenBits Model Railways, All Rights Reserved
27/09/2021
Summary of Contents for Bachmann Class 66
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