Wrexham (Alyn) Engine Shed

Was built in early 1994 to replace a  layout that dropped out of the North Downs Model Railway Circle’s  Exhibition. Model Railway Extravaganza 94 held on the 26 and 27 March 1994. It was decided to build an ex-London North Western Railway (LNWR) engine shed on a small forty-eight inches (122 cm) by sixteen inches(41 cm) base board. The base board size was determined by the need for fast construction. An engine shed was chosen to make maximum use of  available space, the interests of Circle members and the availability of track. Stock availability determined a shed set during the change from the London Midland Scottish Railway (LMS) to British Railways (BR). Access to books and photographs determined ex-LNWR buildings.
Despite the need for rapid construction considerable thought was given to engine sheds facilities and operation. A historic frame work was developed to explain the role of the Shed. ‘Over a thirty year span (1845 to 1875) there were major plans for railway developments in North Wales that would have created a line from Rhyl to Wolverhampton but would have missed Wrexham. The 'marcher' town would have been served by a loop with branches into the Moss, Brymbo and Black Valleys. The shed at Wrexham (Alyn) would provide medium and small engines for the lines round Wrexham. The shed would have been part of the Shrewsbury district probably with 4F as its shed code.’ Information and photographs of similar sized sheds in the area were checked. The sheds at Penmaempool, Corwen and Denbigh were seen as good ‘role models’ as they were the right size though not as intensively used as Wrexham (Alyn). Interestingly Penmaempool  did not have a turntable or pits so these would not be provided at Wrexham (Alyn).  This decision was reinforced by the limited need to turn engines. As the steep grades round Wrexham, for example Moss branch had grades up to 1:30 (3%), meant engines ran with their chimney pointing up grade to keep the fire box covered with water. Branch termini were unlikely to have turning facilities. It was decided that the essential facilities were a two road engine shed, coal dock, oil shed, water tower and water crane(s). Operation mostly comprises home engines entering the scenic area to be serviced with coal, water and sand before going to the shed. Home engines going of shed for train duty.  Visiting engines coming in to be serviced and return to train duty. The other traffic on the layout is coal, sand, oil and spare parts coming onto the shed and ash going off shed. Research suggested that there would be peeks in the requirements to service engines. To meet this the water cranes were located between two easily accessible tracks speeding the tempo of servicing.
Wrexham (Alyn)’s baseboard was an early attempt to build a light and rigid baseboard from 6 mm ply. It comprises a deck to which were glued sides, front and back. While the glue set the joints were held together by pins and angle clamps. Two lengths of ply are glued under the deck creating a horizontal ‘V’ stopping  the layout twisting. The back scene is also made from 6 mm ply and adds rigidity the layout. The baseboard has met it goals and has given no problems over the last five years. The main point learnt from this layout is to allow joints to set before moving the layout.
The layout uses Peco flexi-track and long radius points. Long radius points are unusual in a layout this size. It was felt that they would give a better appearance, lead to smother running and when planning the layout it was found that smaller radius points had no major advantages. Point control is by wire in tube. Experience of operating at exhibitions has shown this to be a reliable system and present’s no ergonomic problems on small layouts. The control panel is built into the back of the layout. This location was determined by a desire to minimise the amount of wire used, avoid plugs, have fewer solder joints to go wrong and speed construction. The layout is, as you might suspect, heavily sectioned allowing up to twelve engines on the layout, eight in the scenic area and four in the fiddle yard.  Switches are ‘double pole centre off’ allowing operation by two controllers in practice operation is usually by a single controller.
Engines entering and leaving the scenic section would cast a shadow on the back scene so it was decided to treat the back and sides of the scenic section as retaining walls. Given their relatively low height it was decided to take the retaining wall to the top of the back and sides. The retaining walls are made up of ply covered with a main layer of Slaters Plasticard ‘cut stone’ then a partial layer representing abutments. The entry and exit point is partly hidden by having the engine shed come as far forward as possible. The exit was made to look like a road bridge by a bridge girder made from Slaters Plasticard. 80 ’thou’ plasticard with microstrip webbing. Surprisingly small engine Sheds like Wrexham (Alyn) operated twenty-four hours per day with a morning, afternoon and small night shift. Staff not only include drivers and firemen but a shed master (manager), technical staff (a fitter on the morning and afternoon shifts) and support staff; cleaners, coalmen (handling coal, ash, etc.) labourers and steam raisers. In 1955 Denbigh Shed operated seven engines and had a staff of forty-two. Railways gave considerable thought to the provision of facilities required by the staff of an engine shed. For example the shed master’s office would, if possible, be placed were it had the best view of operations. Provision for these facilities is made in the low section of the engine shed comprising, from front to back; shed master’s office, Signing on point, lobby, toilets, canteen and fitters store. The engine shed was planned using LNWR Portrayed  by Jack Nelson. The model is an open box of 60 thou’ plasticard covered with Slater’s 4-mm plank that is also used for doors. Windows are framed with microstrip and glazed with Plastiglaze made opaque by several coats of mecpac. The roof is Slaters pantiles. The coal dock and base of the water tower are made of card with the side covered with Plasticard ‘cut stone’  Slaters paving stones cover the top of the coal dock. The water tank was taken from a ratio kit. Oil for lubrication and illumination present’s a fire hazard and was often kept in a separate building. An oil store was built with a core made from 60 ‘thou’ plasticard covered in 'corrugated iron' from the same source. A small shed was provided to store sand a similar approach was taken but the sides were covered in 4 mm planking and the top in fine wet and dry representing a felt roof. The bike shed and water cranes are kits. All though more expensive than brick paper Plasticard was used throughout to give more texture and detail that I feel is important on small layouts. When I glued the Plasticard to the side of the retaining walls for some reason it started to bubble. I ‘shawed up’ the wall with bits of balsa this hid the problem and added to the scenery. Ballast was stuck down with the usual mix of half water, half wood glue with a dash of washing up liquid. I add Indian ink to ‘dirty’ the ballast.
Matt paints are used through out as I feel this gives a more realistic effect. To obtain an extra matt finish paints are allowed to separate and the thicker ‘grinds’ used. As plasticard has a glossy surface it required two coats to matt down. A variety of paints (Humbrol numbers given) where used on the layout. The Pantiles on the engine shed are painted brick red (70) that is also used on track and chairs to represent rust. To represent wood preservative timber buildings and sleepers are painted dark brown (86). Black (85) is used on the bridge and the inside of the Engine Shed. Stonework is painted sand (63). To bring out the texture and to tone down the yellowness the stonework was given a wash of equal amounts of hemp (168) and thinner. This was done a little bit at a time so that the stonework could be horizontal while the wash was applied and dried. Finally the layout treated with a wash of one part black to five parts thinner representing the effects of decades of industrial grime and steam trains.
Considerable thought was given to vegetation on the layout it was felt there would be two types. The centre front that had probably been allotments during the war would have reverted to relatively luxuriant grass, weeds and small bushes.  This was represented by a part layer of  Woodlands Scenics course turf and a full layer of fine turf. Grass, weeds and moss could appear anywhere and where created using fine turf. A range of shades was used to give a natural appearance. The turf is fixed with photomount. Experience showed that it was advisable to allow 12-24 hours drying between each ’gluing’.
 Research suggested that the engines based at Wrexham (Alyn) would be a mix of Jinties, 3Fs, 4Fs, 2Ps, 4Ps, and 4MTs. Visiting engines would tend to be larger including Black 5s, 8Fs, etc.. The goods stock includes LMS and BR open wagons for coal and ash with vans for sand, oil and spare parts.
Engines come onto the shed run along side the coal dock to be serviced. Ash is put onto the ground when it cools it is shovelled into wheel barrows moved to and shovelled into empty coal wagons. Coal is wheel barrowed across the coal dock to coal engines. Watering and coaling can be carried out simultaneously. If a higher tempo is required both sides of the coal dock can be used for ashing and coaling and both sides of the water cranes for watering.  While ashing, coaling and watering engines are oiled and minor maintenance is under taken. If an engine is urgently required it may receive only a part service. After servicing engine are move to the engine shed or return to train duty.  Engines coming out of the shed normally go directly to train duty as they have been previously serviced. 
Goods traffic comprises open wagons going to the siding behind the coal dock with coal in and ash out. Vans come from the main shed at Shrewsbury with sand, oil and spare parts and go to the siding in front of the shed. It is possible to move cold (out of steam) engines round using a pug that also handles the goods traffic. 
Development of the layout continues. Recently it was changed from a table sitter to having its own set of legs. The legs support a shelf allowing a greater range of stock to be operated. To give a better appearance the front and sides have been stained. Incidentally dark stain is used as transit damage is less noticeable than with paint or varnish and a dark surface does not draw the eye away from the scenic section of the layout. There are plans to add further details.