March 2004 Progress report
article by: John McMillan
This quarter has seen us getting to grips with some of the "big
shiny bits" on the locomotive. Just before Christmas we had fitted
the remaining coupling rods, and in the New Year we took delivery
of the completed cab which had been fabricated and painted at
Ropley on the Mid-Hants Railway.
To re-fit the cab, it was necessary to shunt "Owsden Hall"
first, then our locomotive, into the open air to give the delivery
lorry's crane room for manoeuvre. This was a testing time for the
coupling rods to ensure there was no binding, and there were some
heart-stopping moments before it was realized that stones lodged
under the wheels were preventing the diesel shunter from
withdrawing its heavy load into the yard. When the stones had been
dealt with (ground down to dust!), the loco ran sweetly to and fro,
and we were happy that all is well with the rods and bearings.
Meanwhile the cab was lowered on to the loco frames, and after some
heaving to get it lined up with the bolt holes on the loco, we were
able to secure it in place. Apart from fitting the window frames
and installing electrical wiring in the conduit runs to
connect switches and lights, the cab is now complete.
Within the cab we have replaced the floor boards, and have been
putting fittings back in place ahead of our pipe-fitter's return to
do more work, so the boiler back-head is now looking quite complete
with all its cladding painted and in place. Also, the reverser
control and drive shaft have been re-fitted so we can see how well
the boiler crinoline strips line up. As anticipated, there is a
slight height discrepancy which will result in some cutting out and
re-welding of the strip to compensate.
With the cab back in place we have been able to assess how well
it aligns with the boiler and the boiler crinolines. The cladding
on the boiler barrel has to fit underneath the cab with sufficient
clearance to allow the boiler to move as it warms up. The boiler is
bolted to the locomotive chassis at the smokebox end and expands
backwards, becoming approximately ¾" longer when up to temperature.
The crinolines, although made to the drawings, appear to stand off
from the sides of the firebox a little, and the supporting stools
will have to be trimmed back to fit. It's as well that we are
finding these discrepancies now, rather than after the fire-box
cladding sheets have been made.
Apart from the finished cab, we have also received the
connecting rods at Toddington. The outside rods were last seen as
rough forgings lying around the yard, but now they have been fully
machined as part of a batch of rods being produced for Southern
Locomotives for their numerous Bulleid Pacifics, an arrangement
which has saved us a great deal of money. The rods await a lot of
work to remove small machining marks on their surfaces, partly to
improve their appearance but mainly to remove points where stress
cracks or corrosion could form. The inside connecting rod is an
original (from 35029), and has received its surface polishing
treatment already. They all require their bearings to be machined
before fitting, but we now have a complete set of rods for the
locomotive.
After the marathon effort involved in completing the cab
windows, the never-ending job of machining pipe-fittings has
resumed. An order has been placed for all the copper piping we
anticipate needing to complete the locomotive; a faint glimmer of
light at the end of the long tunnel, perhaps?