A Surface-mounted Sector Plate
By John Rodway from Gazette Vol 20 No.8 August 2018
The tall industrial buildings that form the backdrop on Gillan and Brown provide an excellent location for the sector plate subterfuge that adds to the operation of the layout
Sector plates can be useful where off-stage
space is tight. On Romiley Methodist
Railway Modellers Gillan & Brown industrial
layout (Gazette: August 2008, Layouts to
Inspire, 2016) there are two. One carries whole trains
and gives them access to the back-stage storage
sidings / fiddle tracks. The other is within a building
and allows single wagons to be transferred to and
from a track hidden behind a factory. Here incoming
loads can be conveniently removed or outgoing
loads added, unseen by the audience. The two
sector plates use different designs to match their
contrasting sizes and function.
The longer sector-plate is conventional, in that
it is a plank of 9mm ply that moves within a pit in
the baseboard surface. Such recesses take time to
cut accurately and they permanently commit that
baseboard to their initial position.
By contrast, the smaller sector-plate is surfacemounted,
requiring just two holes in the
baseboard, one for the pivot and the other for the
electrical supply. Should changes be required,
nothing irreparable has been done to the
baseboard.
This smaller sector-plate is based on two
lengths of flat-bottomed rail soldered to copper
clad paxolin sleepers in the usual way. It simply
slides over the baseboard. At the pivot end there
is a more substantial rectangle of cooper-clad
paxolin, held to the baseboard with a bolt, washers
and nuts. As with the sleepers, the copper is
thoroughly gapped to prevent electrical shortcircuits.
Though this track is inherently rigid,
repeated movement would stress the limited joint
areas between the sleepers and rails, especially
when carrying a loaded wagon, so two substantial
angle brass longitudinals were sweated to the
extremities of the sleepers and to the pivot plate.
This view from the operators’ side clearly shows the brass handle used to change the alignment of the plate and also the gap in the buffer block to accommodate auto couplings on stock. A wagon arriving on the sector plate can be moved, by hand, onto the track inside the building, bottom left, to have a load removed or added before returning to public view. The recess into which the removable building fits is also clearly visible.
Also attached to the pivot plate is a buffer stop. Since this is concealed from public view, it is just a
block of metal soldered to the ends of the
longitudinals and the pivot plate. However, there
is a central gap to accommodate the loop of
Winterley couplings, and a horizontal hole on the
operators' side into which fits an L-shaped rod.
This rod is held in place by a clamp nut, a former
gas fitting, and forms a handle to move the sectorplate.
The handle projects through a horizontal
slot in a modesty screen that clips onto the rear of
the baseboard.
To further enhance the illusion, the spaces
between the rails and the longitudinals are filled
with thin ply, painted with the same palette of
mottled colours as the floor of the building and the
concrete pad outside, though grading to darker
colours close to the buffer-stop.
This screen partly shades the interior of the
building, making it difficult for the public to see
what is happening within the building. It also
prevents the public from the embarrassment of
catching a glimpse of the operators' tummies -not
always a pretty sight. To further distract the public,
their side of the screen is painted with indistinct
blocks and stripes of greys, browns and whites,
giving the impression of the interior of a large
engineering workshop. The screen still allows
operators to move wagons from above by fingerpower.
For storage, the handle and screen are
removed.
Viewed from the front of the layout with the building removed, this shows the sector plate aligned to the incoming track. The
operators’ handle projects through the rear wall of the building.
The ‘roller’ door to the building is only raised
when wagons are to pass through. They partly
block the view of the interior from the viewer’s
side. As a further distraction, there is a twoaspect
electric light signal on the wall outside the
doorway. By the use of a micro-switch, this only
displays green when the door is fully raised. It is
not a stop-go signal, as on running lines. It just
gives the driver permission to shunt wagons at
will in either direction, with assured overhead
clearance. This sector plate has been in use for
over 15 years, during repeated testing sessions, for
many hours of operator training, and at
numerous exhibitions. The only problem has been
one of the insert strips breaking loose, and it was
easily re-glued in place.
Since this article was written, the Gillan and
Brown layout has been sold, becoming privately
owned. The sector plate described continues to
function in its new home.