ATTAM BANK Our Current Layout
| Trackplans | Layout Philosophy | History | Layout Photos |
Description
The Layout consists of a scenic section, two end-boards and the fiddle yard.
Vital Statistics
Layout Size: 25ft by 7ft
Scale: 00 (4mm=1ft; 1:76)
Track Gauge: 16.5 mm, Track Standards DOGA Intermediate Control System: Digital Command Control, DCC Location Modelled: Anywhere on UK secondary main lines Period Depicted: Any from 1930 to Present Day* Motive Power: Depends on period/area being exhibited (currently "Somewhere in Southern England, May 1944") Viewing Arrangement: Proscenium front, top lit; plus right side demonstration area. * Non-Pantograph areas only post-1976
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Scenic Section: Four 5 ft x 2 ft baseboards, with a double-track rising at 1:100 from the left (viewed from front) across the first board, becoming level half-way onto the second board. On the third board the track divides into four, continuing as four-track round the right-hand end-board to the Yard. There is a single trailing cross-over between the up and down main lines. The plain track is SMP bull-head, the pointwork hand-built on copper-clad sleepers with Code 75 bullhead rail. The pointwork will be operated by DCC-controlled point-actuators. |
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End-board right: Four track with (layout) minimum radius (up slow) of 21 inches. Track hand-built on copper-clad sleepers with Code 75 bullhead rail. There is a crossover between the up slow and the up main, plus one between the down slow and the down main. Again these will be operated by the new point-actuators, but installed so that their operation can be observed by the public at exhibitions |
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Fiddle Yard: four 5 ft x 2 ft 6 inch baseboards containing the 14 road Yard. All the points are solenoid operated via SEEP motors, which are themselves controlled by DCC accessory decoders. The trackwork in the Yard is Peco Code 75. |
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End-Board left: Two track with minimum radius (up main) of 23 inches, no pointwork. Track hand-built on copper-clad sleepers with Code 75 bullhead rail.
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A copy suitable for the website is in preparation
General Approach : As mentioned in History of the Layout, the layout boards had been built and the track-plan decided before any of the current members were involved. However, it was early on decided that as far as possible the scenery should contain nothing permanent (eg. bridges, fencing, trackside fittings etc) that could not have been seen on any UK secondary mainline during the period 1930 to present-day. Our idea is that the scene can then be dressed to permit exhibition running in various modes from the thirties to the diesel era, in any part of the country, depending on what stock was available from the Members. Hence the name ATTAM Bank - All Things To All Men.
Scenic treatment of the Layout : Scenic set-pieces and major items such as the signal box & signals will be made to be demountable and easily replaced for a different "presentation" of the layout.
To this end we are working on
DCC-operated removable signals (with bounce if semaphore). The 1975
cutoff is because that was roughly when all lever-operated signal boxes
were replaced by central power boxes, and the pantograph became much
more common. We decided we wanted a traditional signal box to help pin
the display to a given location/era, and that removable overhead wiring
was a step too far! [we are still debating the "third-rail" question]. Obviously
later non-pantograph trains (eg. Virgin Voyager etc) could still run
without looking out of place or time if we forgo the signal box [or
have a derelict one!].
When it comes to trackside items that have to be fixed, the most widely-used items have been chosen - fortunately these items tend to be small so only the most dedicated rivet-counters will spot when they happen to be out of area. Examples are the cosmetic chairs used on the hand-built copper-clad sleepered point-work - these will be three-bolt pattern (not GWR 4-bolt), and the GWR manufactured its own individual type of point-rodding unlike the fairly standardised patterns used elsewhere. We shall adopt the fairly standardised patterns used on most other UK lines.
Operation of the Layout :
Initially there were plans to incorporate turntables at each end of the
fiddle yard, with loco laybys to permit trains to return onto the
scenic section in the opposite direction and headed with a fresh loco.
We later decided this would mean too much shunting, and decided to
simplyfy and operate/exhibit the layout in
a "roundy-roundy" mode, to give the public what they
mostly seem to want to see - trains running - and to rely on some
scenic set-pieces hopefully to keep their interest beyond the 60 second
average that observation at exhibitions has shown many layout viewers
spend before moving on. In particular, we feel nothing seems to thin the crowd
round a layout quicker than a stalling loco or a derailment; these are
definite no-no's. Therefore all locos and stock will be cleaned and
tested before an exhibition, including checking the wheels and
point-work still meets the running standard for the layout, which is
the DOGA Intermediate Standard (NB: still called "Commercial Standard" on the DOGA website). Currently we aim to have a minimum of 18 trains running
in a logical sequence at scale speed. [GRAPH] We estimate the sequence
will last for a minimum of twenty minutes to complete. More than one
train sometimes will be on the scenic section at the same time, eg.
down crossing up train, down or up main train overtaking the equivalent
slow train. In both directions loose-coupled unfitted freights will
need to pause on slow lines at top of bank to pin/release wagon brakes.
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BMRC was formed in November 2003. However, only one of the present Cheadle Hulme Group was a member from the start; the rest of us joined at various times later, by which time the double-0 layout, Attam Bank, had been designed and the baseboards built.
Originally the track-work was all Peco code 75, including point work, except for some hand-built points on the end-boards. Track wiring for the usual direct current control, with resistance controllers, was completed to the point that we could run trains round the layout on both the up & down main-lines, and we actually had an Open Day in May 2005 when this was done.
The roads in the fiddle yard each had been wired in three sections to a system we named Bi-directional Linked Isolator Control [BLIC]. This allowed trains to enter/leave the road in either direction, or for one train to enter while another left at the opposite end, or even for two trains to both enter (or leave) in opposite directions at the same time. The fiddle yard control panel section was completed in time for the open day. Wiring diagrams were prepared for the running lines, using cab-control, and wiring the baseboards completed on the end-boards and the four scenic section boards.
Then we started to fit and wire the point motors, with diode-matrix controlled route-setting in the fiddle yard. All this work was largely finished when the decision was made to rip up the Peco track and points on the scenic boards and to relay with SMP code 75 bullhead track and hand-built point work constructed with SMP code 75 bullhead rail on copper-clad sleepers.
The hand-built point work on the four-road end-board had give some trouble in running sessions, so the further decision was made to lift and re-build this. In the event we lifted all the Peco track on both end-boards as well, and agreed a simplified track plan, with only two points on the four-track end-board instead of the previous six points distributed over both end-boards.
But before this work had really got started, another, fairly momentous, decision was made - to convert the whole layout to Digital Command Control [DCC], and to control not only the locomotives but also the points and signals this way.
So out had to come all the hours of DC wiring, and new - admittedly much simpler - DCC wiring installed.
[Pics of wiring before and after here]
This wiring had been done in the fiddle yard, and the new track and points laid on the scenic section by mid-October 2006, when we got our "notice to quit" the clubroom (see page About Us > Our History). |
The layout in the store-room: Scenic and End boards in rack,
Fiddle Yard boards on left.
