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Plankton is my first layout. It's intended to be a small fun shunting layout where I can develop my skills and play with ideas, set in the late 70s somewhere in the fictional Scotland in my head, where rail transport receives subsidy that's at least proportional to that of roads, and air-braked wagonload freight fits between turn-up-and-go passenger services on lines purposefully worked close to capacity. I've always had an interest in railways, and had a few 00 models as a kid, but layouts never progressed beyond ambitious track plans. I came back to railway modelling when I found I could make a cheap base station with DCC++, cheap block detection with current transformers and an Arduino, and thus build a layout with working signalling and interlocking. Not that I've managed to get the block detection to work yet, but I'm working on it! Plankton started out as a 1200x200mm baseboard for an unknown modeller's uncompleted layout. It sat in my local MRC's scrap pile for a while until I nabbed it in 2017. I quite quickly laid down an Inglenook layout, stuck the DCC++ base unit underneath, made a homebrew controller based on another Arduino, and was up and running. The points are motorised with SG90 servos superglued directly to the underside of the baseboard, and with some adjustable feet underneath it has a semi-permanent home in the living room on top of the piano: The original plan had been to cram in Timesaver alongside Inglenook. Perhaps Timesaver could've been a wagon workshop, and Inglenook the marshalling yard for arriving and departing wagons. But when I placed the tracks down it looked very contrived and cramped, with a requirement to stable wagons on the turnout linking the two sections, so I abandoned that idea. This is the new plan - a branch terminus with a run-round loop long enough for a Type 2 + five 15ft wagons (or two coaches), with a crossover to the yard. I've suggested where signals would go - PL is "Position Light", either shunting or subsidiary, and YPL is a yellow position light shunt signal for movement over the crossover onto the main line. Inspired by @Izzy's Priory Road, I think I can get a 450mm sector plate overhanging the edge of the board which can fold out of use - possibly a train turntable. Alternatively the line would continue to the board edge, with a kickback siding for stock storage. The operating pattern would be: 1. With eight wagons and a shunting engine in the yard, assemble five wagons as per Inglenook rules 2. Freight train arrives with five more wagons and is signalled into platform 3. Train engine leaves wagons in platform and runs round back to the home signal 4. Train engine backs onto prepared train in the long siding and departs (into the sector plate road it came from, filling it) 5. Shunting engine collects wagons from platform into yard (pulling forward into an empty sector plate road) 6. While shunting takes place, DMU or prototypically short loco-hauled passenger train arrives and departs from the third sector plate road, giving a rationale for not using the extra space of the main line and loop for shunting. I want the signalling to be colour light, partly because I like colour light signals but also because I am deeply unenthusiastic about making working lattice-post semaphores in N gauge. Also because the idea of building an NX panel is what brought me back to railway modelling. Now, "colour-light 1970s branch terminus" is a bit contrived - maybe it's a short urban/suburban branch included with the resignalling of a larger station and controlled from its signalling centre as a rationalisation measure and operated under Track Circuit Block. Or maybe the line is Absolute Block and there's a signalbox and signaller at the terminus, and scope for simulating block instruments. I was scratching my head a bit about how to signal freight trains departing the yard. Should they get a starter signal, should they just proceed under the authority of the yellow shunting signal, or should there be another Up signal on the other side of the two turnouts to the platform starter? Since making the diagram I've decided there'd be another signal a short distance down the line. Next steps will be to get block detection working as this will inform how the rewiring goes, lift some of the track, remove the controllers from the board edge, then give the whole thing some paint. I'm pretty tired of staring at the blue board!
Here's the track diagram, set in ex-SER/LCDR territory pre-1913 (hence red distant signal at 24, and ringed shunt-ahead signals on the platforms): A few small notes: x and y represent a train length distance, as well as the boundary of the main layout. From 'x' to 'down' (and 'y' to 'up') is on a separate optional board. the blue section, levers and signal is the next signal box block, after which there is an immediate exit to a FY. It is neccesary to support moves from the Down line, over the crossover and towards Y (but not the home signal) to shunt the FY - hence the placement of this box's home signal and the use of a second block. For this diagram/signalling solution, I have not included any interlocking for turnouts A and B forming that crossover, or ground signals C/D, or that box's Advanced Starter lever 24 represents a distant signal for this box the group of six levers 18-23 is the home signals for this box - there is no direct access to platform 1 from the up main, so it is omitted. Here is my understanding of how the interlocking would work - there are a number of implicit locks, for example Lever 1 platform starter being pulled off, is only contingent on lever 10 being off already - but lever 10 is contingent on lever 11 being off, and so on. Summary: Each turnout is locked by specific requirements and geometry (i.e. for 12 to be closed, 13 must be closed also) The Distant is unlocked to pull off by available platform route indicated by home 18, 20 or 22 Each Home arm is locked by outbound starter/shunt signals from the relevant platform Each platform starter is mutually exclusive with all other platform signals, since the next signal is the following boxe's home signal Each platfom shunt ahead signal is exclusive with its own starter I would really appreciate any thoughts or comments on this one!
Hayling Island Signals. Currently, on my 00 gauge layout of South Hayling Station, the two Home Starter signals for the main platform and the bay platform are standard Hornby semaphore signals and I am planning to remake them to match the original signals and to make them work, including DCC Concepts working rodding. South Hayling was always said to be unusual in that the main Platform Starter was a “normal” Southern Region upper quadrant signal while the bay Platform Starter was lower quadrant probably, it was said, a signal that came second hand from another region. A lot of “hand-me-down” equipment ended up on the Hayling Branch line. From this photograph, it is clear that originally both Platform Starter signals were lower quadrant. Unfortunately the photograph is undated but, it appears that the Terrier is sporting an early BR logo, which should put it into the 1948 to 1956 time period. More recent photographs show that the No.1 Home Starter was replaced with a very short SR upper quadrant version made from re-used rail. Where an engine appears in any of the photographs showing the newer upper quadrant signal, those engines have the later BR crest. In addition, the bay Platform Starter is unusual in that the ladder is on the facing side of the signal with a vertical hand rail that runs in front of the signal arm. These are two of the working signals that I am building. However, I also found a copy of the 1957 signal plan for South Hayling Station: I wanted to understand the way that the signals worked and interlocked, so that I can recreate the signals as close as possible to the original. However, I am definitely no expert at signals and I am hoping that someone who does understand the intricacies of signalling can help sort out a few things that I don’t understand. My understanding (I hope) is that in order to pull “On” the lever in the “Work” column, one must first pull “On” anything in the “Release” column, then ensure that anything in the “Locking” column is “Off” (pushed back) before pulling the “Work” lever “On”. It appears that the Facing Point Locks (Nos. 1 and 4) are locked when “Off” and unlocked when “On”, everything else is at Danger when “Off” (for signals) or at normal when “Off” (for points). Hoping that I am right so far, this leads to a number of questions of things about which I am not sure: 1). On Nos. 1 and 4, does the “in nor pos 6 6” and “in nor 5 5” mean that the FPL can only be unlocked when the relevant point is in its “normal” or “Off” position? 2). There are two 7 ground signals, one facing away from the station (7 Pull)and one facing towards the sidings (7 Push). FPL on 6, lever No.1 appears to require both of these to be “Off” (at danger). Does this mean there are two levers – or if not, how can they both be “Off”? 3). To pull No. 5 or No. 6 “On” does not seem to require the appropriate FPL to be “On” or unlocked, or am I missing something? 4). Lever No. 6 seems to operate both the main points at 6 as well as the catch points next to 7 Push, presumably via the same set of rods. Is that correct, two points with the same lever? These are the catch points next to 7 Push. This is a photograph of the main points at No. 6. What is the linkage on the middle left and what does it do? Is it controlled by Lever No. 6 or lever No.1? 5). This is a photograph of the back of the tiny signal box at South Hayling. You can clearly see the ladder on the face side of the starter signal on the right. I can see the rods that work from levers 1, 4, 5 and 6 and that cross the track on the right to run down to points 5 and 6. There also appears to be a signal wire running from the pulley at the bottom of the starter signal on the right, across the tracks to a pulley under the three rods. But that leaves at least six signal wires unaccounted for. You can see some of them in the photographs above, of the Catch points and Point No. 6, running alongside the track, but how do they get there? Any Ideas? Any and all help very much appreciated! All the best, Echini.