Dunedin

I was also at Haymarket open day in 1985. I was on 37401 and my former colleague Ray Murison was on 47715, which was named Haymarket during the open day by Robbie Coltrane, I think. It was Ray who really knew the details about the workings of the two-wire control system as it was known. I owe my knowledge of the system (and also many other locomotive systems) to him, but he did a good job of passing it on. Ray sadly died at the beginning of 2014, but below is a photo I took at Haymarket in summer 1986: Ray is the one in the leather jacket. It was the only item of clothing he had which he said actually looked better after being in the engine room of a Class 47! The loco in the photo is actually 47715 undergoing a traction motor change. It's very likely that it was Ray who answered your questions about whether the two wire control system was FDM etc. I doubt whether many other people there would have known!

Hi Derekstuart, I'm glad you and others found the spot interesting and informative. The 47/7 and DBSO system in Scotland was designed and supplied by Brush and was an FDM system, so it modulated different frequencies to transmit the different channels/messages used to control the loco from the DBSO and for the loco to send messages back to the DBSO. The systems used on the West Coast mainline and East Coast mainline were designed and supplied by Plessey and they were (are) TDM systems so the different channels are transmitted during predetermined, discrete time-slots in a predetermined sequence. Interestingly, the Mark 4 coaches on the ECML use TDM to control the Class 91 from the DBSO, but they also have an FDM system as well. This is used for control within the rake and is used for air conditioning control, lighting control etc. Another interesting feature of the Brush system was that Channel 1 which was "Engine Start" on the Class 47/7 was also described in the manual as being "Pan Up & Reset" on the Class 81 loco! The Class 81s were never fitted, but the system was designed to be used with them. For each Class 47/7 channel, there was an equivalent described in the manual for the Class 81.

Q5: Originally the push-pulls worked the Edinburgh - Glasgow (E&G) route and because of the frequent and heavy braking, it was decided to use disc-braked coaches. The original Mark 2 sets were converted for this reason. Later, one of the reasons for using Mark 3 coaches was because they came with disc brakes as standard, so no conversion costs. All the original DBSOs were converted to disc braking for the same reason, but the later DBSOs, which were converted to the Aberdeen services retained their tread brakes. 9714 was the only exception; this was intended as the replacement vehicle for 9706 which was written off in the Polmont disaster in 1984. In the end, it was too difficult to manage two pools of DBSOs, so any DBSO finished up getting attached to any set. Wherever possible, the Mark 3s were used on the E&G route, but occasionally when Mark 3 availability was low, a Mark 2 Provincial vehicle (or sometimes even more, up to a full set) were used as cover. There was also the business spec from Provincial Services which specified the best stock for the premiere route(s). The reason for preferring disc brakes is mainly because brake pads last longer than brake shoes, so disc-braked stock on routes with heavy and frequent braking cost less to maintain and use less man-hours to do so. As an aside, another by-product of the heavy braking was the exam regime on the 47/7s: On normal locos, they would be "blocked" when they needed it - i.e. they would have the brake blocks changed as and when they were identified as wearing thin. That might have occurred during an exam, or at a fuel point visit. On the 47/7s, the regime was, that if they were due an A Exam, they would be blocked, or if they needed blocking, they would get an A exam. Their daily diagram mileages on the E&Gs were similar to HSTs, so they were being really hammered. 100MPH running didn't help in that respect either, compared with 95MPH for normal 47s. Q6:I always remember it as 5, 13, 30 and 50! Diesel locos such as the Sulzers and English Electrics had all-speed governors on the engines, so there were no speed notches as such on the controllers. The power controller operated a regulating air valve, which fed air to a cylinder in the governor. This then operated the fuel racks on the engine, via a set of complicated levers and linkages. An oil vane motor in the governor also controlled a potential divider on earlier locos or a linear voltage differentiating transducer (LVDT) on those converted to ETH, to vary the excitation current in the main generator. This enabled the output from the generator to match the load the engine was capable of delivering for the regulating air being fed from the power controller. The Brush/Sulzer system was very well designed and it was almost impossible to overload the engine. Back to the 5, 13, 30 & 50. This relates to the regulating air pressures. When the power controller was moved to the "ON" position, this fed about 5psi of air pressure to the governor. It didn't increase the engine speed, but enabled the engine to supply enough torque to apply a small amount of tractive effort at idle speed. With the controller at 1/4, the regulating air was about 13psi and the engine would run faster and be able to deliver a greater load. The oil vane motor would increase the output from the potential divider/LVDT and the excitation current would be increased and the main generator would produce correspondingly more voltage and current for the traction motors. As a result, tractive effort was increased. 30psi was somewhere between 1/2 and 3/4 and 50 psi was full power. When the loco was being driven from the cab, the regulating air pressure was infinitely variable from 5 - 50psi, but from the DBSO, that couldn't be achieved, without running a regulating air pipe down the train to the loco. A regulating air pipe was a standard feature of all Blue-Star multiple working locos - you can see these on the buffer beams of Classes 20, 25, 26, 27, 31, 37 etc that used Blue Star multiple working, together with the 27 way electrical control jumpers. The regulating air pipe is the one painted white. The original Class 27 push pulls used this feature and the converted Mark 2s were fitted with regulating air pipes and the 27 way jumpers. For the two-wire control push-pulls, standard stock was to be used, so no expensive conversions, apart from the DBSOs. These had 4-position EMU type power controllers so another solution had to be found. The solution was quite clever: The four power notches were translated by the two-wire control equipment into 4 power demand channels. When those signals popped out at the other end, they energised four power notch relays in the two-wire control cabinet on the loco. These, in turn energised four separate electro-pneumatic valves that fed air into the regulating air system. Notch 1 gave 5psi, 2 gave 13psi, 3 gave 30psi and 4 gave 50psi. This made the train less easy to drive in propelling mode because the control wasn't as fine, but the drivers soon got used to it and actually preferred driving from the DBSO because it was quieter and gave a better ride. Hopefully this give a little more insight into how the system worked. It (and the Class 20s at Haymarket) helped to pay for the deposit on my first house!

Just to follow on from Graham's post yesterday, here are some photos taken around the fuel points: The original fuel points were modified Knightwing bases, but for the new part of the layout, I decided to scratch-build the bases and then re-use as much of the old equipment as possible. As I wasn't going to be constrained by the number of bases, I also decided on extending the fuel points and to add some additional canopies etc. As a result, the new fuel points will consist of new, scratch-built bases, a mixture of existing canopies and some new ones which I've built. Whilst I didn't have any more fuel pumps etc., I decided to build another two from scratch. These will be fitted with "trigger" delivery nozzles for fuelling DMUs - the Class 150s and early Sprinters didn't have the flyte refuelling valves that are fitted to locomotives and HST power cars, so I can justify the additional canopies etc. for those! To deal with spillages, fuel points generally have bunded areas to catch spills of oil, fuel and coolant which are then fed to an interceptor which separates out the contaminants from the water so as not to pollute the sewers. The bunded area is often in the form of a shallow concrete pit over which the tracks are laid and in order to provide a surface for staff to walk on etc. and avoid anyone falling into the pit, they are covered by steel grilles. I've tried to simulate this using plastikard for the concrete and brass mesh for the grilles: The north-end fuel point (HST fuel point nearest the camera - this is one of the re-claimed ones. The second, third and fourth canopies are new and still need to be weathered.): The south-end fuel point (loco fuel point nearest the camera, HST fuel point furthest away. New canopy in the centre, which will house a staff shelter.): New fuel pumps right and centre, with the Knightwing original to provide a pattern left: Pumps and staff shelters painted in primer, ready for final colour to be applied:

More work on the layout today and Graham brought the maintenance shed extension over to try for size. You can judge for yourselves from the photo, but not bad, I'd say (but don't tell him I said that)! This afternoon we made a trip to DEMU Showcase in Burton to spend yet another small fortune on stuff for the layout. We also had a chat to the folks on "Caverswall", who are also the organisers of the Crewe and Alsager Society's exhibition. The upshot of our discussion is that we won't be attending the show this year. This gives us more time to get things to the standard we want to achieve and means that our first show after completion will be Derby 2017 at The Roundhouse.

Thanks. Yes, the garden sprayer works really well. I had been trying to find something that would speed up the process: previously I had tried the hand trigger type of sprays and using a pipette but these either didn't work particularly well (the spray ended up more of a jet that washed everything away), or in the case of the pipette, it just took ages. With the garden spray, you can pressurise it before you start, adjust the spray nozzle to get a fine mist and then just spray, knowing it will stay consistent. I reckon it saved me hours, so was worth the cost of the sprayer.

Ballasting of the track on Boards 4, 5, 6 & 7 is now complete! Phew! It's been a long job and come to think of it, I've probably done almost as much as on the original layout in total and I've still got the mainlines to do on Boards 1 - 3, but that won't be such a big job as this has been. As Graham mentioned, the new ballast, although claiming to be the same shade as I had left over from the original layout, actually turned out to be lighter. I'm assuming that was due to it being a different batch, but I've had a play with the airbrush and some very dilute "Sleeper Grime" and I'm now satisfied I can get the two different shades of ballast to match, where I need them to by judicious weathering. Looking back, I should have expected this and not ballasted all of one board with the contents of one tub and started the next board with the contents of another. It would have been better to have used the different tubs for mainline, or yard etc. where you might expect the shades to be different, but that's hindsight for you! The weathering will hide it and of course, at some point, I will be adding snow again. Here are some photos of progress and the finished job: Boards 4 and 5 before ballasting started - note the track hasn't been weathered yet, so is still very bright and shiny: Board 4 during ballasting, before glueing: Board 4 just after being sprayed with the glue (this is a mix of water, washing up liquid and PVA glue): Board 4 complete. Board 5 had also been ballasted by the time this was taken and in addition, you can see the bases for the new south end fuel points (more of these to follow in a later post): Boards 6 & 7 before ballasting had started - you can see that the track in the yard has been weathered, but at this point, not the mainlines. Weathering is just sleeper grime, applied with the airbrush. This is mainly to tone down the rail colour and I think that sleeper grime looks better than Humbrol rust colour, but either way, it's a pain to apply by hand, so airbrushing is far quicker. For the wooden-sleepered track in the yard, it looks fine if everything is covered, but for the concrete-sleepered track of the mainlines, I needed a decent coating on the rails but wanted the sleepers still to look reasonably light. I discovered that applying the sleeper grime, then rubbing it off the sleepers, before it had fully dried, with an old toothbrush (with some bristles removed) worked quite well. In this view you can also see the bases for the central and north-end fuel points: Boards 6 & 7 during ballasting: Board 7 taken this morning after completion: The next jobs are to complete the wiring of Board 7 and make a start on the scenery. In order to save time, we have decided to get the fiddle yard boards made by a local joiner. The seven boards would have taken us about two months to build, working at weekends, so when the quote came back looking reasonable, it was a no-brainer! In order to save time / allow more time for getting the main viewing boards to exhibition standard, I've also begun to think about breaking one of my golden rules in the case of the fiddle yard: Electrofrog points and every piece of rail having its own directly soldered connection to the DCC power bus. Precise, slow speed running isn't necessary in the fiddle yard, so I reckon Insulfrog points will be ok, which means I don't have to worry about frog polarity changeover switches and all the associated wiring. As we are not ballasting the track there, I also think we can rely on rail-joiners to carry the current, at least in the short-term. The mixture I use for glueing the ballast is pretty corrosive due to the washing-up liquid. This is used to lower the surface tension of the water, so it doesn't wash the ballast away when it's applied, but washing-up liquid also contains salt, as a water softener, which makes it corrosive. Once everything has been soaked in that, it can create high resistance joints between rails, hence my obsession with everything being soldered for reliability. I think five years fault-free running with Kirkhill proves the worth of this approach, but maybe, just maybe, I'll make a temporary concession for the fiddle yard. The points can also be hand-operated initially and can be motorised later, using surface-mount motors if need be. All this will save a considerable amount of time (if we need it), hopefully without compromising performance, at least to begin with and we can improve the fiddle yard as time allows.

Following a break for Easter, things have moved on again this week. Before the main lines could be laid, the undersides of the new extensions to Boards 4, 5 & 6 needed to be painted. This was done on Tuesday. The boards had to be split from each other and laid on their sides for the painting, so I made a start at wiring since I had access. I can't do everything until the mainlines are in, but I could make a start with the power feeds to the depot lines and install the point motors and wire them. The photos below show progress during today. Board 4 with feeds connected and point motor wiring in progress. Tag strip with feeds from panel to points on Boards 4 & 5. Nomenclature for wiring to Point 13 as an example. I don't colour-code the control wires; I number them, so Point 13 has two switching wires - 13N for the normal position and 13R for the reversed position. The common feed is not numbered, but this is the only wire on the layout that isn't. Each point is fitted with Peco motors and micro-switches. One set of switches is used for the frog polarity and the other will be used for points position detection on the panel. This won't be installed initially, but it's easier to put all the wiring in now. Point 13 detection wires are 113N and 113R for normal and reverse respectively. The common detection wire is simply notated as D. The coloured wires below the tag strip are the multiway jumper cable to the panel. Tag strip for connection to jumper from Board 4 to Board 5 points. This view also shows a close-up of the DCC power bus and droppers connected to it. These are colour-coded because I only need two colours (although it turns out to be 3!). For each track, I use red as a dropper for the rail at the rear of the layout (from the public viewing side) and blue for rails towards the front. These are soldered onto the bottom of each rail before the track is laid, holes are drilled in the board, then the droppers are poked through as each length of track is laid. Every rail has its own dropper - the only thing the fishplates do is align the rails mechanically; they aren't needed for carrying current. This way, by the time I've ballasted and everything has been soaked in a corrosive solution of PVA, water and washing-up liquid, if a fishplate goes high resistance, it doesn't matter. The power bus under the board is twin & earth lighting cable with the outer sheathing and earth removed. I plan where the droppers will be so I can minimise the run of power bus, then the droppers are soldered to the bus: blue to blue and red to brown (hence the three colours). Semi-complete Board 4 - main lines and Point 13 to add. Board 5: point motors installed (still to wire) and track droppers still to connect to DCC power bus. You can also see the yellow wires here from the point frogs. These run to the switches on the point motors.

In the end, I added the maintenance shed inspection pit and a couple of lengths of track. The pit is held down with four fixing screws - one at each corner, so the plasticard floor needs to be glued back in place.

More progress to report this week - being on holiday has helped somewhat! Track-laying has been in progress on Boards 4, 5, 6 & 7. With the exception of the main line, it is complete on Boards 4 & 5 and nearly complete on Board 6. I reckon another decent day would do it, but that probably means several evenings in reality. I've annotated the attached photos so you can see more easily how things are progressing and how it will all fit together: View from Board 4 looking north towards Board 7. Trains will usually arrive onto the fuel point from the north, heading towards where this photo is taken from. There is also a single-lead access to/from the main line to the south. View from Board 7 looking south towards Board 4. Looking in the opposite direction onto Board 7 showing the approximate position of the fuel tanker off-loading point, north access to the maintenance shed etc. The new (and old) location of the wheel lathe. This will enable a headshunt beyond the lathe, allowing more than one vehicle in a rake to access it without the need for remarshalling. The new location of the maintenance shed, with the alterations which are necessary to make it fit the new location. I'm off to the garage to do another late shift and see if I can complete the track-laying on Board 6, or shall I cut the hole for that inspection pit.......?

I included that specially for you, Steve!

The new Board 7 was painted last week, which meant we could finally begin track-laying last Sunday. Hooray! This started with the removal of the old fiddle yard and the laying of the new fuel point: Getting the alignment correct before actually laying the track: The points for the depot junction: Do we name it Kirkhill Junction or Wellington Road Junction, as it will be under Wellington Road Bridge? We're going to change the point at the depot end of the fuel point tomorrow night from a medium right hand point (SL-E95) to a large radius Y (SL-E98) because this will give us about another 4 inches of straight at the fuel point and means we don't have anything on a curve. The junction at the far end isn't quite where I drew it on the CAD, because I hadn't made allowances for my torsional stiffener, which has ended up beneath the board right where the point motors needed to be. This means the junction has had to move in about 2 inches, with a corresponding effect on the fuel point. Such is life! You begin to see in these photos just how much larger Kirkhill 2 is going to be - and this is only just over half of the length. Cripes!

We're certainly hoping so - and intending it to be!

Thanks. The mainline is intended to stay as double track round to the fiddle yard in both directions. The depot junction takes the track from the depot onto the Up Main, so there will be a further crossover to the Down Main for trains heading from the depot to Aberdeen. On the plan, I haven't drawn both lines beyond the crossover, which is why it may be unclear. This will be on the bridge board before the fiddle yard, but the intention is to keep the mainline double so we can pass trains should we want to/need to. It would of course be simpler to reduce the main to a single track off-scene, but this will mean more operational restrictions, so I'm hoping to keep it double. As Graham said, we may need to simplify some things off-scene for the first few appearances, but I'm hoping we can retain this part of the plan.

Since Graham has said I might post an update, I suppose I'd better do it then! Board 7 is an entirely new board, being at the right-hand end of the plan that I posted on 31st January. This board both lengthens the layout, enabling us to fit the new fuel point where the fiddle yard was and it will also carry the mainline round a curve, through the junction onto the depot and onto what will be a new bridge board to the new fiddle yard. It will also have the new Wellington Road Bridge which will cross the mainline and form a scenic break on the curve. As a result, it is quite large, being basically 4ft x 4ft, with a corner chopped off. Board 7 with the torsional stiffener added underneath: I thought we may need two diagonals, but one has proven to be sufficient. Board 7 mated to the existing, extended Board 6: Board 7 with the points for the depot junction laid on loosely and some flexi-track for trial-fit. This is to make sure that the positions on the plan translate into reality and there are no cross-members under the board where the point motors need to go! On this last photo, you can see that part of the board is now covered with cork. This is the depot area. The mainline and the junction will also sit on cork, but it will be cut as a template under the track, so that it helps to create the impression of a ballast shoulder. We don't need this in the depot area, so everything will be on the same level. Doing this also means we don't have any height transition between the depot and the mainline through the junction, so things should run smoothly and reliably. I've also painted the top of Board 7 this evening with undercoat.

Thank you. That's certainly the intention anyway. We don't have any confirmed bookings after Crewe in November this year. We had invitations for 2016 for Model Rail Scotland, Turner's Folley and Chatham, but these had to be declined due to our year off. I am hopeful that we will be invited again next year, but time will tell. I am also hoping to get us a follow-up article in Railway Modeller early next year, so that should also assist in generating renewed interest on the exhibition circuit - in addition that is, to this thread!

The other thing I haven't added yet is the track plan for the new layout (the old one plus the alterations), so here it is:

More progress this weekend: Board 1, the last to be extended has had its extension added: This board doesn't join to anything else at this end, so this is where all the tolerances stack up so this is where all the slight differences in length of the components become apparent, hence it has been surformed to neaten off the end. The join between boards 1 & 2 has worked well too. I've also begun to cover the extensions in cork, to provide the base for the track etc. in the same way that we did for the original boards. The easiest way I've found is to glue cork flooring tiles on to the plywood. I've stapled the edges to help stop them lifting while the glue sets. The change in construction method seemed to work well and as I said last week, results in a stronger board, so I've begun to add cross-members to the other boards as well. I did 5 and 6 yesterday. I've also made new end boards to the new width for Boards 5 & 6. The rest to follow.

Another weekend, another day spent on the layout. This time, we intended to extend Boards 1 & 2, but in the end we only completed Board 2. We finished up changing the method of construction again, this time due to shortage of the 1" square section wood that we have been using for the strengthening gussets. Our new method mirrors the one we used for the original boards by constructing a ladder frame. It actually results in a better job, which will be stronger, but it takes longer to build. It would have been quicker to have spent an hour going to B&Q to buy more wood! The ladder frame: Then the top board was nailed and glued in place, which is the same as previously. We also filled in the hole which had been for the inspection pit module, which can be seen in the previous photo. The inspection pit will be re-sited to the new location of the maintenance shed. This photo shows the completed extension on Board 2, married up to Board 3 to check the fit (which is perfect).

Two more boards extended today - boards 5 & 6: Next job on these two is to remove the back scene, the wheel lathe (including the pit) and lift the track in the fiddle yard. Shame about the back scene and my chain-link fence, but they will (hopefully) be re-used elsewhere alongside the new mainline. The wheel lathe will be relocated to alongside the maintenance shed.

The method we came up with is the most pragmatic way of extending them. As with the originals, the boards are 9mm ply, nailed and glued together with softwood gussets in the corners at the joints. This provides something to nail into. We can't nail the extensions onto the original boards, so we screwed 25mm-square softwood through into the gussets on the original frames and then nailed and glued the extensions onto them.

More stripping of Kirkhill Boards 3 & 4 today: Fiddle yard backscenes and Wellington Road bridge have now been removed from Board 4: Wellington Road bridge will be reincarnated on the new Board 7 at the right-hand end of the layout as part of the scenic break. The fuelling points have been removed from Board 3 and stored safely for re-use; these were two loco fuel points and an HST fuel point. The train wash will now take their place, so all trains draw forward from the new fuelling points (the existing ones, recycled) on the site of where the fiddle yard was and proceed through the wash. The 08 will then take rakes to the maintenance shed or cleaning roads. This is the trial-fit to ensure that once the longest vehicles (Mark 3 coaches) are past the points and straight enough to clear the wash plant, there will still be sufficient length for the longest trains to fit into this road, clear of the wash.

Yes, forgot to mention the buffers. The TGSs also had drop-head buckeye couplers and draw hooks instead of the usual fixed-head buckeyes of the HSTs, but only at the loco end. As pointed out by BR(S), they also worked with the Class 89 on the East Coast for a while. According to Colin J Marsden's HST Silver Jubilee (Ian Allen 2001), there was a "short-lived" service intro on the WCML in December 1987 and presumably that is where photo of 43123 at Birmingham New St comes from, but that is just an educated guess. How long that lasted, the book does not say. According to the same source, the surrogate DVTs ran with the Class 89 on KX - Peterborough services from July 1988 on the 07.16 Peterborough - KX and 17.36 return.

A busy day today with Graham - we had a board meeting This was the first go at extending the depth of the boards for Kirkhill, so in at the deep end - Boards 3 & 4 got the treatment: Rear backscenes removed Extensions constructed and added This was the result by 5.30 this evening: Board 3 - the hill is going to need some significant surgery. Boards 3 & 4 together - the bridge on Board 4, which forms part of the scenic break, will go (along with the rest of the scenic break) and a new one will be situated on the new Board 7 at the far right hand end from the viewing side. Once I'm satisfied that this method works and is stable, we will get on and extend the other four boards.

Yes, it's just the lights and the windows. Cooler groups and other roof details are the same. The first two conversions (43123 and 42014) were the prototypes and were used on the West Coast for a while with Class 86s etc to prove the TDM control system. There were no HST servicing depots on the WCML that had any power car expertise, so the engines were isolated temporarily. It was intended that this would be permanent at first, so without any auxiliary alternator output, there would be no power for battery charging, cab air conditioning or other auxiliaries. These first two were therefore fitted with motor alternator sets in the guard's vans and a standard BR 850V - 1000V ETH supply with a jumper cable and socket at each end. They also had RCH lighting control jumpers at the non-driving end so they could transmit the TDM via the RCH cables on the loco-hailed coaches. These are all details that can be added later. After use on the West Coast ended, the 1000V ETH was no longer needed, so it was eventually removed. The later conversions for use with the Class 91s ran with HST trailers and provided the 3-phase, 415V supply for the train, so they were never fitted with the loco-hauled-type of ETH. Quite when 43123 and 43014 had theirs removed, I don't know, but there are photos of them on the East Coast, still fitted in Exec livery. When they were used on the East Coast, the surrogate DVTs also had the UIC-type jumper cables and sockets added for the TDM system, but these weren't used in HST formations. Spare cables in the 36-way HST control jumpers were used instead as far as the TGS. The TGSs on there sets designated for Class 91 workings were fitted with RCH jumpers to connect with the Class 91s RCH jumpers.