Baseboards
Baseboards
The first and clearly the biggest issue was that the layout didn't fit my shed. At 17'6” by 7'6” it was 1 inch too long and 1 inch too wide...what are the chances of that! It wasn't as simple as 'lop and inch off 2 sides.” For a start, either the baseboard frame was within that very same inch or else the track went right up to that particular edge. The other issue was that if you change the size it affects the radius of the curves and then they need rebuilding. Close inspection showed the layout could be narrowed at the western station exit where the main line runs into the lower storage loops. By shortening the loop entrance and exit and bringing the loops nearer the station, the layout width could be reduced by 40mm without affecting the curve. I drew out a plan of the boards and numbered each one to help my understanding - see bottom of page.
I decided to place each board on it's own set of legs and fortunately I acquired some IKEA wooden shelves which would provide a base. These were modified to give the lower loops a height of 1040mm (41”). Each 900mm long shelf section was fitted with adjustable feet for levelling and 2 longitudinal's of 70mm x 44mm timber cut to suit the length of each board. The board was then carried on cross pieces of 44mm x 32mm timber cut to suit. This substantial construction had the effect of reinforcing the weak base boards, providing open access underneath and giving plenty of storage space.
The storage loops are the most complex part to get right so I started there. The upper 'East' storage loops (representing London) used to sit on raised hinges attached to the lower West loops board (representing Devon and Cornwall). The chipboard had given up at these points so an alternative attachment system was required. The upper board (6) was simply thin chipboard with no support. I'm sure this was to give clearance for the lower loops and minimise the gradient linking the two levels. I decided to compromise and screw 15mm thick planks under the upper board to strengthen it and to provide more substantial attachment for the hinges. This meant the upper board needed to be raised to give a clearance between boards of 60mm. A seriously chunky construction of timber was build directly onto the leg sections and protruded through the lower loops board (5) to take the weight of the upper board on it's hinges. It had the effect of shifting the upper loops towards the centre of the room by 40 mm and therefore skewing the whole length of the track on the St James Park section by the same amount. The upper picture shows the East loops board (6) in the lowered position with the new timber support and hinges at the rear. The lower picture shows the upper loops board in the raised position. (and the as yet untamed copper 'spagetti' wiring for the loops control panel). You can also see two of the three blocks fitted to support the upper board when lowered.
Once the loops were installed and the lifting section worked correctly I commenced building shelf/leg units for each of the 3 boards (2,3 and 4) through the main station section. A gradient would need to be introduced as the track rose from the lower to the upper loops. Overall this worked out at 1:90 but as only a small rise could be applied to the station area due to the sidings or the corners, it meant that the plain track either side of the St James Park section would take the brunt of the rise at 1: 70. This was achieved by the leg adjusters and packing the cross bearers under each board. I did manage a small 1:150 incline through the station which helped the height gain without causing the goods wagons to congregate at the buffers.
Exeter central station boards on shelf/leg units
View looking west
View looking east
The fourth station board numbered 1 (right) was another problem as it crossed the door way. The board held the eastern throat point work, part of the carriage shed and sidings so ideally it wouldn't be a lifting section. Although I put a low handrail down to assist me ducking under, I still wanted it lifting. The board is 1370mm long (54”) and if pivoted at the end would hit the shed roof when raised. By placing the pivot on the front edge of the leg unit some 400mm from the board end, I got the lifting portion to around 900mm (36”) long which didn't hit the roof when open. As the pivot was now towards the centre of the board it caused the rear end to fall in a kind of counterbalance reaction to the lift. It means that one end of the board drops to line up the tracks whilst the rear end rises to line up. Seems a bit odd but it works.
Lifting board showing pivot moved inwards by 400 mm from end.
Lifting board with end board fitted
I now laid in the 3 boards working back from the upper East loops (6), on a falling gradient through Black boy tunnel (7), St James Park Halt (8) and east corner (9) towards the main station. They took a bit of 'persuading' to accommodate the 40mm slewing of the loops and yet get the final corner board back into it's correct location to meet the end curve. If this re-alignment failed, then the whole Eastern throat and the end curve would need rebuilding on a new smaller radius but it seems to be OK.
You can see how the embankment, made from plaster bandage is separating from the supports and baseboard. The only bit of backscene is a hand painted view of house backs and 'St James Park' the Exeter City AFC football ground.
As expected, the East end board (10) between the East corner (9) and the lifting section (1) didn't fit but at least this was the only part which needed serious adjustment. The end board was shortened by 25mm (1") in the plain track section and although it fitted in, the tracks didn't align at both ends.
Modifying the East end board (10) involved various shavings being taken off the end together with the baseboard end frame being moved by threading it between the point motors allowing the requisite 'inch' being cut tight to the track leaving just 10mm clearance on the end curve. Again the embankment has parted company as has some of the track.
This shows the misalignment before the end board was modified. As the end board only held a crossover and one turnout, it was arranged so these tracks lined up as close as possible with the station throat on the lifting board in order to minimise subsequent adjustment.
(Above) End board showing misalignment with the corner board (9) at LHS. The track misalignment was now in the order of 20mm so a good 300mm of track was removed pending reconstruction on a slightly smaller radius to tie between both existing tracks.
(Left) Shortened board fitted and misaligned track stripped back pending rebuilding - See 'Track' section. (Below) track in place and embankment rebuilding underway.
All in all I consider it a bit of a victory that only this small section needs correcting. Overall I now have the layout in the shed, on it's legs and roughly aligned. The next stage will be to fettle and repair the track so that something can physically run.
Baseboard arrangement