Laying out the foundation
of the box - perhaps the hardest bit of
Another photograph of the first two
courses. In the middle of
|Three courses on and the main steel to
support the locking room
floor, and then the lever frame assembly itself (estimated at about
two tons) has to be installed. In common with many GW boxes,
we used rail. The two rails extending through the front wall of the
box form the foundation for the lead-off bed.
|Putting in the locking room floor - the timbers are
wide (although they vary from one another by a little bit),
over 19 feet long, and eight inches deep. Try getting those
from B & Q!
|On the locking room floor sits the timber
truss which supports the
cast-iron frame in which the levers sit. The one end of the truss is
supported by a vertical timber which sits on the floor in a cast shoe,
and then is held by the operating floor joists at the top. The other
end is built into the coal house wall.
|We wanted to be sure that no excess pressures were to
from cast-iron which did not sit true, so the most important part of
the day was to check it was all level. The verdict - not bad for
timber which dates from prior to 1896!
|The front of the box from the plinth
level upwards is supported
by two bridge rails about 18 feet long. The one was original which
we brought back from Wrangaton. Sadly the other was perished
and we had to replace it. We managed top find a replacement
from a disused traverser bed at Wolverton works. The bridge rail
sits on three pedestals and is built into the brickwork at either end.
This hole in the wall is where all the rods and wires come from the
inside of the box to the lead-off bed in the front, and from there to
points and signals.
A crane was used to lift
the frame into position on the timber truss. The castings
were all very heavy, but light work was made by the
crane, and it all bolted together very easily, once we
More pictures will
appear soon of the construction and
|The cast-iron frame in position, all
bolted up, but strangely, not
bolted at all to the timber truss. The weight and design of the frame
ensures that it does not move at all. Eventually, spacers are
installed at the top of the casting (where all the forces are felt from
moving levers) which are attached to the operating floor joists, and this prevents any excess movement.