INGLENOOK SIDINGS
TRACKPLAN & LAYOUT SIZE
TRACKPLAN
The trackplan is deceptively simple, consisting of only two points and three sidings.
As with most shunting puzzles, the length of the sidings is determined by the operating rules. In the case of Inglenook Sidings, the longest siding holds 5 wagons, while the two others have a capacity of 3 wagons each. The headshunt allows for the engine plus 3 wagons (when operating, a total of 8 wagons plus one engine will be used).
LAYOUT SIZE
The resulting overall size of the layout is small by any standards, but can vary considerably as the actual length of the sidings is determined by the common length of the rolling stock to be used on the layout - the longer the rolling stock used, the longer the sidings will need to be.
Left: A preserved private owner 10t open coal wagon (10'-0" wheelbase) [September 1992. Didcot] / Right: A Departmental ZRA 29t van (20'-9" wheelbase) [May 1990. Bristol East Yard]
(Both photographs copyright and courtesy of the Tony Dunkley Collection)Alan Wright's original layout only measured 1' by 4' (30cm x 120cm). This was achieved by using standard goods wagons of the British steam/diesel transition era which are comparatively short: the standard wheelbase measures 10'-0" (3m), which gives a total length over buffers of 20'-6" (6,15m). Scaled down to 00 gauge, this translates into goods wagons about 3,2" (8cm) long. Therefore, a siding with a length of 20" (50cm) will easily hold 5 pieces of rolling stock. Modelling modern image (or a completely different prototype), things can get a little bit more complicated. There might still be some items with a 10'-0" wheelbase and hence a model length of approx. 3,2" (8cm) around, but the majority of stock will be longer (the ubiquitous VDA for instance has the "modern standard" wheelbase of 20'-9", which scales down to a total model length over buffers of approx. 6" / 15cm), and this will have to be reflected in the length of the tracks. Tank wagons and special purpose stock will also be of differing lengths. Therefore, the longest type of rolling stock to be used will have to serve as the standard rolling stock length in order to define the length of the sidings, i.e. multiples of 5 and 3 thereof.
In the case of rolling stock of various length being used, an additional rule needs to be introduced in order to prevent chance constellations where it would in fact be possible to squeeze e.g. 6 wagons onto the 5 wagon siding.
The choice of locomotive used will, of course, depend on the prototype being modelled, but small to medium sized shunters are a logical choice. Most British layouts seem to feature 0-6-0 tank steam engines or 0-6-0 Class 08 diesel shunters, while the General Electric 44-ton four-axles switcher is a common favourite for US layouts. A Cl 08 shunter fresh from the paintshop shunts a short-wheelbase VEA van in the sidings at Little Bazeley.
SMALLEST INGLENOOK POSSIBLE?
The set-up of Alan Wright's original Inglenook Sidings only required a layout space of 4' x 1' (120cm x 30cm). As pointed out above, modelling a modern rather than a steam/diesel transition period prototype will inevitably result in a longer layout due to the longer rolling stock used. If, however, you do not have more space at hand, you might wonder if cutting down on the 3-3-5 formula might make a modern Inglenook possible within the same 1' x 4' (120cm x 30cm) layout limits. The answer is yes, but certain points need to be observed.
Carl Arendt, master of micro layout design, has subjected the Inglenook formula to some practical testing and found that it can be cut down to 3-2-2 with a 2 cars plus loco headshunt and still provide operating interest, forming a four car train from a total of six cars randomly placed in the sidings. This example illustrates just how flexible the Inglenook formula is: you can fiddle around with the track capacities, and you can alter the total number of freight cars on the layout, together with the number of cars to be assembled in order to set up the departing train.
Bob Hughes' N Scale San Vince de Rey (a tongue-in-cheek reference to the fact that this layout is actually built on a sandwich tray) works on a 3-2-2 "reduced" Inglenook Sidings formula. Set in California, it portrays a small yard in Union Pacific territory. A micro layout by any standards, it can be kept virtually anywhere.
Even a "reduced" Inglenook layout offers an operational challenge and is fun to operate, even though the reduction in complexity of the shunting puzzle which results from such alterations is far more significant than most people would suspect:
number of cars number of different
arrangements of carsnumber of cars in
train to be made upnumber of possible different
trains to be made upClassic Inglenook 8 40,320 5 6,720 Carl Arendt Micro 6 720 4 360 "Minimal Inglenook" 5 120 3 60 The reasons for this drop in complexity are explained in further detail on the shunting puzzle theory page.
The conclusion to be drawn from this is, perhaps, that from an operational challenge perspective it is better to stick with the original formula if at all possible. On the other hand, even a "minimal Inglenook" is better than no Inglenook...
One thing, however, which needs to be observed very strictly, is the capacity of the headshunt, i.e. the track leading up to the points. This needs to hold at least the loco plus the number of cars equivalent to the capacity of the two shorter sidings (i.e. 3 in the classic formula). If this rule is ignored and the capacity of the headshunt reduced, there are a number of car arrangements will actually prevent the loco from pulling out the last car from the long siding, turning it into a sitting duck.
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Page created: 01/MAY/2001
Last revised: 22/FEB/2007
