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Dave Holt

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  1. Dave Holt
    The shorter porting of the FPL lock bar has now been completed and fitted in situ - still waiting for the glue to set. This just leaves the connection to the FPL bolt. I think I'm going to have to modify part of the bolt mechanism already fitted as it doesn't allow a long enough connecting rod to the lock bar. Not quite as drastic a mod as Coachman regularly makes to Greenfield but a bit of extra work with the added risk of damaging parts I need to re-use.
     
    Here are some photos showing assembly and fitting of the shorter part of the bar.
     
    First a shot of the rod having the pivot levers fitted. I used a simple plastic card jig to help me get these correctly positioned so that they fall in the middle of sleeper bays. 145 degree solder was used to avoid unsoldering the vertical mounting pins or melting the plastic too much!
     

     
    Here's the finish section of bar with the bottom of the pivot levers trimmed to clear the top of the track underlay.
     

     
    Finally, a shot of the bar in situ with hair grips holding it in the correct position whilst the glue sets. I put the adjacent section of board in place to ensure the bar lined up across the joint. It also allows me to position the stools for the remaining section of point rodding which moves the whole lock bar/FPL arrangement. Visible in front of the RH grip is the bolt operating lever which needs to be moved one sleeper to the left.
     

  2. Dave Holt
    A quick update following completion of the FPL lock bar operating mechanism. This includes a representation of a spring assister which helped the signalman move the weight of the bar and cushioned the bar at the ends of its movement.
    Still got the other portion of the bar to complete and the rodding from the signal box.
     
    Here's a view of the recent bits added:
     

  3. Dave Holt

    Delph - FPL lock bar

    By Dave Holt,

    Following on from my previous post on point rodding, I've now got stuck into the facing point lock lock bar. This is located immediately in advance of the king point to prevent the FPL being withdrawn if any stock was standing over the bar.
    Using information from the Scalefour Society manual and further information and photos from Robin Whittle (of Barrow Road fame) I've made good progress with my 4 mm scale representation.
    The bar is slightly the wrong proportions being a length of 0.82 x 0.82 mm Tee section but not too far out. It's mounted on wire pins set into the base board top adjacent to the rail. The pivot levers are from an Ambis FPL etch but I didn't bother with the associated support brackets as they're barely visible behind the pivots. I set the top of the bar 0.75 mm below the rail head to make sure that my 0.5 mm deep wheel flanges would be clear of it. This is perhaps a bit generous clearance as the real thing is about level with the bottom of the rail head in the lowered position. To get the bar to the required height I had to file the top of the inside chairs to 1.57 mm below top of rail and trim the bottom of the pivot levers which will be below ballast level when all is finished.
    A minor inconvenience is that the bar crosses a base board joint, so the total length (50' - 6") is split with 140 mm on one board and the remaining 62 mm on the next.
    Here's a photo of the longer section in position. Also visible (just) are the cranks for the operating rods (rods not yet done). The drive from the signal box lever is to the far (left hand) end of the bar.
     

     
    At the other end of the bar is the attachment to the FPL bolt mechanism. This arrangement meant that any failure/breakage in the lock bar arrangement prevented the FPL (and hence the point blades) from being moved.
  4. Dave Holt
    It's been quite a while since I last posted anything about Delph (or should I say "Holt"). This is mainly because there's been precious little progress in recent weeks, partly due to the warm weather making work on the layout an unattractive proposition but mainly because I've been shying away from what seemed like a difficult and fiddly task. Needless to say, when I actually knuckled down to it, it proved much less of a problem than I had anticipated.
    Anyway, a concerted effort over the past week has seen good progress and it now only remains to do the facing point lock (which straddles two base-boards) and the cranks outside the signal box.
    Here are some shots showing the main rodding run, complete with compensators, and the arrangements to get the rods across the entrance to the mill siding.
    First, the main rodding runs. In the second photo, the hole in the base-board is for the starter signal to plug in.
     

     

     
    And here, the rods pass under the track into the mill siding, seen from each side. An Alex Jackson uncoupling magnet can be seen under the middle rod.
     

     

  5. Dave Holt

    Delph - 9F visits

    By Dave Holt,

    BR 9F 92037 paid a brief visit to Delph today following major repairs. Here she is seen close to the recently installed FPL and signal detector.
     

     
    The loco last saw use at Scalefour North a couple of years ago. Unfortunately, it shed a con rod big end (due to the return crank unscrewing) which locked up the chassis at full tilt and doing a fair bit of mischief to the mechanism. The loco was stripped down and now everything appears OK, although not tried under power, in anticipation of an appearance on Robin Whittle's fabulous Barrow Road layout at the forthcoming S4North show in about 10 days time.
    Even if now fully restored, I don't think 92037 will get much use on Delph - holiday excursion perhaps?
     
    Dave.
  6. Dave Holt
    Recent progress has been rather slow and has included cosmetic point stretcher bars on all the points forming the main station throat and a start on the point rodding in the same area. Of course, at the real place, there wasn't much point rodding because the signal box had been removed in the early 1900's and subsequently the points were operated by local levers. However, in my model I've reinstated the box and so rodding and signal wire runs are required. The rodding run connects the box to the two cross-overs and the facing point lock controlled by the signal man.
    I've opted to use MSE cast white metal rod stools which are a lot less fiddly than the fabricated etched brass type and actually represent the LNWR stools slightly better. Rodding is represented by 0.4 mm square section N/S wire, also from MSE. Some of the cranks and rod end eyes are from Ambis etches. I'll also be using Ambis stuff for the FPL and the point blade detector.
    I have temporarily fitted rodding into the stools in order to locate them for fixing down to their mountings to give a smooth run (as best I can).
    These photos show the progress so far:
     

     

     
    A couple of general views showing the rodding run, from where it passes under the track between diamond crossing and the mill siding point, to the king point and FPL. Also visible are the local point levers for those not controlled from the signal box.
     

     
    This is the attachment to the king point. The two extended sleepers are for the point blade and FPL detector.
     

     
    Here the connections to the double slip (cross-over formed with the king point) and the tandem point (cross-over with the mill siding point) pass under the running line to the loop. Each cross run has a rodding stool, partially sunk in the ballast in the running line 4 foot, just visible near the bottom of the photo.
     
    Dave.
  7. Dave Holt
    Like some sort of UFO, the goods shed has descended from space (the spare bedroom, actually) and landed in the prepared cut-out in the cork surface of the base-board. It's been there before, but I thought I'd re-fit it, just to complete the station scene.
     

     

     

     
    Dave.
  8. Dave Holt

    Caprotti valve gear

    By Dave Holt,

    In a recent blog, Tim has shown his developing model of an LMS Caprotti Class 5, and very good it looks too.
    Here are some photos of the gear I made for the similar BR Standard version. Also a sketch of how I represented the universal joints in the shafts. THe shafts and joints were made for various diameters of brass tube and rod and the return crank gear boxes were from the DJH cast brass gear I was replacing. For ease of assembly, painting, etc., I made the gear as a set of sub-assemblies held together by small 14 BA) screws. The photos were taken by Barry Norman, so I hope he doesn't mind me putting them on here. The original prints are much sharper but have lost something in the scanning!
     
     
    The assembled gear looks like this:

     
    The various sub-assemblies are:
    1) Cylinders with slide bars and connecting rods,

     
    2) Main drive shafts,

     
    3) Reversing shafts,

     
    These make up the overall assembly,

     
    The universal joints consist of a pair of interlocking "ears" filed onto the end of a length of 1.5 mm tube, mounted on a length of about 0.8 mm wire.

     
    Cheers,
     
    Dave.
  9. Dave Holt
    Hope you all had a good Christmas and are ready to celebrate New Year in whatever way suits you!
     
    I recently collected the platform sections and other Delph (well, Holt, actually) related buildings from Gravytrain, following some minor repairs, additions and modifications. Peter was very keen that I fix the platform sections down to the boards to avoid any further warping of these long, thin plastic card structures - so I have. I'm a little concerned at their vulnerability, especially the lamp standards, during handling and storage for the remainder of the build process. However, too late now!
    I used Evo-stik contact adhesive, allowing it to fully dry, especially on the underside of the platform to minimize the risk of damage from solvent fumes, before positioning the platform sections and weighting them down with substantial steel weights borrowed from the P&O (35006) restoration project I'm also involved in.
    I'm quite happy with the horizontal and vertical alignment of the two sections (split at the base-board joint), but have ended up with a slight gap at the joint - certainly not as tight as the dry run - but it was quite hard to get the exact position and once the glue surfaces touched they grabbed hard and no adjustment was possible. Anyway, it's not too bad.
    The following photos (not the best quality, unfortunately. Also, please excuse the Christmas card background!) show the fixed platform with the station building and signal box placed loosely in position. They won't be fixed till much later.
     
    First, some overall views which also show that the point rodding and stretcher bars, local to the platform, have been painted.
     

     

     

     
    Here's the platform joint mentioned above.
     

     
    Finally, the signal box. The wall at the rear of the platform extends to the box and actually carries on as far as the mill coal unloading bay - yet to be built.
    Recently, I've been having some more detailed thoughts about the mill and it's relationship to the station and the gateway in the platform wall. This has revealed that the track plan is not as close to scale as I originally thought. Seems that a few inches have been lost somewhere along the line (sic). As a result, the unloading bay is too close to the end of the platform. With my original plan to replace the mill with something much more aesthetically pleasing, this didn't matter; but now I've decided to stick to a representation of the actual Bailley's mill, it means some further adjustments will be required. The opening in the platform wall aligns with a doorway in the mill and this will now have to be in a different place along the mill wall than it should be. Still, it's not Delph - see the station name board - so I suppose I'm free to make the necessary changes without altering the overall impression of the place.
     

     
    Dave.
  10. Dave Holt
    In anticipation of fixing the platform in position, I've done some work on the rodding for the platform release cross-over which will be fairly inaccessible once the platform is in position. The cross-over was operated from a ground frame located between the buffer stops via a rodding run which started in the 6 foot, then crossed under the platform road and then ran close to the platform face before crossing back to the far end point blades. I've tried to replicate this arrangement using cast white metal stools from MSE and 0.4 mm square rod from the same source. The rodding cranks are Brassmasters etchings and the point stretcher bars are represented by lengths of plastic strip passing under the rails but not attached. Hopefully, once painted and from a reasonable viewing distance, this won't be too obvious.
    The photos show some of the work so far.
     

     
    The arrangement at the point nearer the buffer stops is slightly unusual. The rodding continues past the point blade attachment (via a lug attachment - not yet modelled) and the passes under the track several sleepers further along. I thing the purpose of this arrangement was to balance the pull/push lengths and so avoid the need for a compensator. Photos of the actual location show no signs of a compensator.
     

     
    Here is the far end connection where the rod passes under the platform road to reach the blades in the loop line.
     

     
    Here's a more general view of the rodding and stools, looking from the buffer stop end.
     
     
    Merry Christmas and Happy New Year to all.
     
    Dave.
  11. Dave Holt
    In my last entry, I reported that I couldn't get the signals to work and suspected some switching problem, which I assumed was due to my attempts at some limited interlocking within the control panel. This requires certain switches to be either normal or reversed in order to allow the circuit to the signal servo control board to be broken, thus clearing the signal. So, for instance, it is not possible to clear the home signal unless the entry point is set to the platform road and the FPL engaged or it is not possible to clear the yard exit ground signal if the cross-over is not set or if if the yard entry signal is already off.
    Anyway, all this arrangement was checked using a resistance meter to check the making/breaking of the circuits within the panel and all appeared OK.
    My next worry was the use of the layout common return for the sevo control return rather than a dedicated servo control return, especially when DCC power is in use because of possible traction signal interference to the servo system.
    Well, I don't really know what had happened, because without making any alterations (other than swapping two of the signal switch connection on one of the control boards which I had connected to the wrong wires from the control panel), when I tried the system a short time ago everything worked OK, even with the DCC system connected. Phew!
    I've also fitted two of the Tortoise point motors with stiffer operating wires to solve a couple of point throw issues.
    Better get on with the point rodding stool supports, cosmetic tie bars, etc., prior to painting the track on the most recent board. Than it's ballasting - something I'm really not looking forward to!
     
    Dave.
  12. Dave Holt
    After the more than slight disappointment of the electrical issues described in my previous blog entry, I am pleased to say the the problems proved not too difficult to sort out. One or two of the comments suggested it didn't sound too bad, so you were right, thanks!
    The dead sections of track were due to me not having connected them to the jumper cable to the next board! I thought I'd been very careful and systematic with the wiring, checking as I went, but obviously not as thoroughly as it should have been. Anyway, three additional wires solve it.
    I couldn't actually find a fault with the platform release corss-over and I have concluded that it is a minor operational restriction due to the way I've powered the track from the crossing units of the points. This appears to cause a problem if the cross-overs at both ends of the run-round loop are reversed at the same time. In practice, this shouldn't cause a problem and just requires the operator to make sure the platform cross-over is returned to normal before completing the run round process. Since this cross-over is operated by a local ground frame (released from the signal box), any engine using it would have to wait, once clear, for the fireman to return the crossing to normal and lock it, then walk back to the loco and climb on board. This pause gives sufficient time for the signalman to change the other end of the loop before the loco moves off to complete the run-round.
    I still can't get the signals to operate, so a bit more investigation of the switching arrangements will be required.
    At least all the track is now powered and all sections accessible. Phew!
    During test running today, I was pleasantly surprised that my ex-LMS Crab 2-6-0 was able to successfully negotiate the very tightly curved mill siding - which is more than can be said for the BR Standard Class 2, 2-6-2 tank, whick derailed the pony trucks. Too striong side control springs, i think.
     
    Dave.
  13. Dave Holt
    Today I had a visit by friend Dave Clarke, who has weathered some coaches for me and we took the opportunity to assemble the whole scenic section of the layout, using the plastic trestles I bought recently. This allowed all the boards and control panel to be connected up and an attempt at running for the first time. A number of unexpected issues were found so the outcome was rather mixed. Part of the run-round loop and three sidings were completely dead on two boards, despite previous careful checking for continuity. I fear that a period of fault finding lies ahead.
     
    Still, we managed to run some locos and stock over part of the layout, so all was not lost.
     
    After moving some furniture and assembling the boards, the first job was to scrape the paint off the rail heads on the main station board prior to trying to run anything. The following photos show Dave doing the scraping and an overall view of the assembly.
     

     

     
    Dave had brought a sound fitted Class 24 and this is seen near the coal drops and also at the head of an arriving excursion train. This is made up of some of the coaches Dave has weathered. He's done a nice job and I'm very pleased with the results - mainly ends, underframes and bobies. The body sides were kept fairly clean on this type of stock.
     

     

     

     

     
    Then it was the turn of my Stanier 2-6-4 tank, No. 42551, to haul the train. A bit more in period!
     

     

     
    Finally, having run round its train (we had to cheat with a bit of finger power over the dead section), the train departs, passing WD 2-8-0, No. 90671, which is standing on the coal drop road, held by the miniature semaphore ground signal.
     

     
    Good fun playing trains for the first time, but a bit frustrating with the problems.
     
    Dave.
  14. Dave Holt
    Those who have followed previous blog entries will know that I have not yet started the support structure for my Delph based layout. As a result, although I have placed individual boards on the (suitably protected) dining table to work on, any attempts to connect several boards together have involved having them on the floor. During a recent visit by Tim V, we managed to connect all four scenic boards, but this entailed moving the table and a coffee table out of the way to make enough space. All a bit of a pain.
    Recently, I have worked on individual boards with them balanced on top a two dining chair backs. A bit precarious, but this has the advantage of raising the board surface to a less back-breaking height and also leaves the table free for its intended purpose! Then a thought struck.... Why not use trestle legs as temporary supports? Similar in height to the chair backs but more stable and leaving the chairs free! So, three pairs of plastic trestle have been accquired and found to be just the job. I haven't tried assembling the whole thing on these, yet, but a couple of sections have been connected so that a couple of loose rail ends could be re-soldered at the board joint. This assembly is shown below:
     

     
    Over the past week or so, I've been fitting the cosmetic chairs to the soldered tack (mainly points, but also some plain track) on the board with most of the station throat point-work. There feels to have been millions of them, even though I've cheated by only applying the chairs to the visible side of the rails to halve the number required.
    In order to fit them, any part of the brass rivet protruding beyong the foot of the rail has to be ground completely away. I used a small grinding disc mounted on the end of a flexible drive shaft to do this - very laborious and causing one or two of the soldered joints to break, needing repair before the chairs was fitted. Each chair moulding has to be cut in half and the cut ends trimmed back to allow the half chair to fit right up against the side of the rail. The chair halves were then attached using a strong plastic solvent (Plastic Weld). I used Exactoscale chairs because they do a wide range of chair types, which helps try to represent the various types of chair present in bull-head rail pointwork. The photos below show the results of my efforts:
     

     

     

     

     
    The next job is to fit cosmetic fish plates at all the rail joint positions. There are lots of these, as all the siding track-work is supposed to be 30 foot rail. Where electrical isolation is required, I'll use the Exactoscale plastic versions and otherwise, Brassmasters etched brass plates. Then it's point rodding supports and the facing point lock arrangement.
    Still lots to do, but it's coming along.
    I hope to have a trial running session next week. If it accurs, I'll post a further item and photos.
     
    Dave.
  15. Dave Holt
    A couple of posts back, I explained how the bell code dinger mechanism had been fitted to the control panel and pondered on possible sources for a suitable battery holder for the PP9 battery.
    Well, nothing appeared to be available commercially, so a custom made holder has been constructed from thick (1.2 mm I think) plastic sheet and attached to the side of the control panel with a couple of 8 BA screws and copious quantities of plastic solvent. The attached photos show the arrangement with the terminal connector held roughly in place using blu-tac. I suspect that actual electrical contact might be more effective in use!
     

     

     
    Dave.
  16. Dave Holt
    By moving some of the furniture, I was able to assemble all four scenic boards for the first time, today. Still on the floor, naturally, as the support structure is not yet built.
    The occasion for this event was a visit by Tim Venton (Tim V), of Clutton fame, following his visit to the Midland Model Engineering Show nearby. Tim kindly helped with the removals work and assembly of the layout.
    Attached photos show the results - looks impressively long for a single line branch terminus.
     
    Two overall views, first from the station end and then from the fiddle yard end:
     

     

     
    This closer shot of the station shows the approximate location for the control panel - right at one end so the operator doesn't block the view!
     

     
    Dave.
  17. Dave Holt
    Yet another step forward with the electrics - nearly there now. I've had two bell code dinger units made to enable the layout operator (driver/signalman) at the front to commincate with the fiddle yard operator (hidden at the back) using prototypical bell codes. These units utilise a modified door bell mechanism (to give single dings each time the switch striker is depressed) operated by a battery powered circuit board at each block post and a change-over micro-switch. Only two wires are required to join the two units - perhaps as well as that's all I'd provided in the wiring loom!
    Any way, the unit for the main control panel has been installed - except for the externally mounted PP9 battery. I haven't sourced a suitable mounting clip/bracket, yet.
    Photos show the dinger cicuit board inside the panel enclosure and the bell and operating switch on the outside of the panel.
     

     
    Dinger circuit board.
     

     

     
    External panel views showing the bell and operating switch. I hope to mount the PP9 battery on the end of the panel, just below the bell.
  18. Dave Holt
    The 12 v DC power supply units for the two signal servo control boards were collected today and then fitted under the boards. There's one power supply unit for each of the control units and these are now all wired up. Another step towards completion of the wiring arrangements.
     

     
    This one supplies the starter and ground signals;
     

     
    and this one the bracket signal.
     
    Next task is to add the bell code dinger unit to the control panel.
  19. Dave Holt
    The signals made for me by Steve Hewitt (of Liverpool Lime Street fame) were collected last week and have been trial fitted to the layout and the operating mechanisms and contol units fitted and wired. Steve has made a wonderful job, as seen in his semaphore signals thread in the forum section of this site.
    The following photos show the signals in situ and the operating bits fitted. The signals have since been removed and refitted into their carrying frames for safety during further layout construction.
     
    First, we see the signals in their layout locations, starting (appropriately) with the starter signal.
     

     
    Next the miniature semaphore ground signal controling the exit from the loop& yard into the running line.
     

     
    Coming in the other direction, we have the home signal. This is a two doll bracket controling entry into the platform road or into the loop/yard. This signal is seen from both sides.
     

     

     
    Now some shots of the under-board operating mechanisms and control units. The operating mechanisms are servo motors and the contol boards are made by GF Controls. I believe they are based on those developed for Lime Street and they each control two servos and incorporate a switchable bounce facility and simple adjustment of the on and off arm positions. The bracket signal unit incorporates two servos to operate the two arms. The others have one each.
    Here's the arrangement for the bracket signal.
     

     
    As I explained previously, space for the yard ground signal mechanism is very tight and I had to re-route a wiring bundle to make room for it. This shot shows just how tight it is. The original route for the wiring was straight through the two redundant wiring clips (fixtures visible either side of the mechanism, as is the re-routed wiring).
     

     
    In contrast, the started signal servo has loads of room!
     

     
    Finally, heres the control board for the starter and yard exit signals. Both controllers have been located so the arm postion adjuster pots can be reached easily from the base-board edge - a very sound suggestion from Steve.
     

  20. Dave Holt
    Complete, that is, except for the signal control units and their local 12v DC power supply units, which I haven't got, yet.
     
    After months of putting it off, I finally knuckled down to wiring up the station throat board with its numerous turnouts and diamond crossing - by far the most complex in terms of electrics. Photos below show the under board wiring on this board.
     

     

     
    However, methodical work and constant continuity testing seems to have paid off as only very minor re-work was required. One heart stopping moment occurred when, having more-or-less finished, I realised I'd run a great bundle of wires right over the space reserved for a signal sevo motor, despite having remembered to keep the area free from electrical track droppers. Fortunately, I was able to divert the offending wires by cutting a slot in part of the base-board support rib, as shown below. It looks a bit odd, but the prospect of having to modify the whole bundle of wires was just over facing! Originally, the wires just ran along the bottom of the member with the lightening holes.
     

     
    Once completed, I checked track feed continuity with a small meter and then conected the power feed from the control panel. In order to do this, all the boards have to be connected as the panel feeds into the station end board and the track power is passed alonf the boards to the oposite end where it connects to the track. Initial power up showed that some of the point position LED's and several point motors needed their polarity swapping - a simple job. Otherwise, my methodical approach seems to have paid off as everything works as intended. This was confirmed by running locos over all tracks on the throad board in both DC and DCC modes from both the main panel and yard controller sockets. I did find that on DC, the loco ran the opposite direction to the switch on y hand-held Pentroller, so the track feeds from the panel and facia sockets have been reversed.
     
    The test session is shown below. A general view of the boards connected together, two standing on edge and the station throat board flat so locos can be run and a shot of the control panel with the point LED's illuminated.
     

     

     
    These tests also confirmed that the sharply curved route into the mill siding can be negotiated by a variety of locos, without any shorting. My Stanier 2-6-4 tank and WD 2-8-0 are seen on the board. The WD is on the curved siding link.
     

     

     
    Not everything was perfect and a few minor (I hope) issues need to be resolved.
    1) Both my Ivatt and BR Cl 2 2-6-2 tanks derailed their rear trucks on the point blades when reversing out of the mill siding. With the cross-over reversed, the trucks went up the head shunt whilst the driving wheels took the correct route over the cross-over. Might havr too strong side control springs on the trucks.
    2)Neither end of the double slip is thowing over properly. The springy operating wire on the Tortoise motors isn't stiff enough to move two sets of blades with the required travel. Hopefully, this can be solved with some thicker steel wire. I believe that 7 mm modellers do this with Tortoises, so if anyone knows the details. I'd be very pleased to receive advice.
  21. Dave Holt
    Following initial function testing of the control panel, I have connected up the panel and two boards to check a bit more, including the yard controller connection points. To my consternation, feeds to the second board (the one with the coal drops) and the DC input were completely dead. Everything on the first (station) board appeared to be reasonably OK (see later) and the DCC input and local point operation/LED's on the second board worked. A slight sense of panic set in as I frantically checked various tag connectiones and continuity. Then, with a massive feeling of relief and realising what a silly mistake I'd made, I noticed that I had only connected one set of jumper cables between the two boards - the other was still neatly held in its clips! Phew!! I sheepishly connected the second jumper and heaved a sigh of relief as everything on board 2 now worked.
    Well, actually, I found that a slight re-thinking of the wiring to the Tortoise point motors was required. I had followed one of the wiring suggestions from Tortoise and used a switched half-wave rectified feed to one side of the motors and one side of the 16 v AC supply to the other. The siding point and associated LED's on the second board worked OK, if a bit slow, but the platform release cross-over, involving two motors and three LED's would only work in one direction. I found that with the LED's removed from the circuit, the motors worked perfectly, so the LED array must be causing too big a voltage drop. I could solve this for the local controlled points by swapping the switches to have an extra pole but the panel mounted switches for he two other cross-overs already were the maximum number of poles available. Mmmm... Then I decided to try wiring the LED's in parallel with the motor feeds instead of in series. I attached jumper leads to try it and thankfully it worked, so it was then a case of rearranging the wiring and connecting on side of the LED arrays, via a resistor, direct to the 16 v AC side which the motors are connected. All now appears to work as intended.
    Next step is to start work on wiring the last scenic board - the one with most of the station throat point-work - that I've been putting off. No more excuses, so I'll just have to knuckle down and make a start.
  22. Dave Holt
    The part finished ex-LMS D2008 vestibule brake 3rd has been completed to partner the D1916 version already done. As before, the bulk of the work was done by Coachman, leaving me to make the interior and finish off. The D2008 is a bit unusual because it has only 51/2 seating bays but an even smaller brake compartment than the D1916, which has 6 bays. This must have resulted in very generous leg room for excursion passengerd who chose to sit in this type of coach.
    Here's a shot of the complete coach and also a closer view showing the brake compartment and half seating bay.
     

     

     
    Here the two coaches are seen together for comparison.
     

     
    Dave.
  23. Dave Holt
    Following a couple of days break attending the Wells Finescale show (helping(?) Robin Whittle and the team with Bristol Barrow Road), Today I got round to function testing the control panel - as much as I can without it being connected to the layout, at least. Everything appears to work as intended but I was puzzled why the LED's indicating the route set by lever No. 4 weren't illuminated whereas the similar LED's for lever No. 8 worked fine.
    Then it dawned that until connected to the Tortoise point motors there was no circuit (No. 8 has a ballast resistor associated with the facing point lock). I then realised that I could simulate connection to the Tortoise by temporarily connecting a ballast resistor between the point motor feed and one side of the 16 v AC supply. As I made the cannection there was quite a spark and I noticed that the 12 v DC power LED had gone out. I then noticed that several other LED's no longer worked. Oops, lesson learned. Don't make temporary connections to live circuits or when the panel is powered up. Fortunately, I had plent of spare LED's and it didn't take too long to replace the damaged ones.
    All working OK again, now!
     
    In between finishing the panel wiring, I have been working towards finishing a couple more ex-LMS Period III open brake coaches made for me to finish off, by Coachman. These are to diagrams 1916 (6 bay) and 2008 (5 1/2 bay) and appeared at ends of an enthusiast special that visited the branch, hauled by an ex-L&Y Class 27 0-6-0.
    The work to complete includes making & fitting the interior, fitting the roof and connecting the water tank filler pipes, spung buffers and making & fitting the P4 bogies.
    The D1916 is now done, as shown below:
     

     
    The interior for the D2008 is currently being painted.
  24. Dave Holt
    Well, as best I can tell prior to functional testing, the wiring is complete. I've tried to be methodical and careful, but even so, I had to undo various cable ties and the spiral sheaving a couple of times to add extra wires which I'd missed first time. Testing under power will start shortly - probably next week, after a two day visit to the Wells show over the week-end. I just hope it all functions as intended as I don't really fancy fault finding or any re-wiring!
     
    Here are some photos of the completed panel:
     
    First, the external view showing the finished mimic panel, lever frame switches and DC track selection switches.
     

     
    Second, a view of the panel base unit and the inside of the two sections of the front panel, showing the wiring arrangements.
     

     
    Finally, here's the power supply unit which supplies 16 v AC to the panel, and then to the base-boards. Inside are two Guagemaster transformers wired in parallel. Both the mains side and output side of each transformer is protected by fuses. The track power feed from the panel are each providied with a thermal trip in case of a short circuit across the track going un-noticed.
     

     
    Dave.
  25. Dave Holt
    Slow progress (all my progress seems to be slow!!) has been made with the control panel. The mimic diagram is complete, including lettering using Letraset transfers (applied by good friend, sign-writer, Phil Taylor - his work is much neater than I could achieve). The diagram was drawn using coloured permanent marker pens.
    Wiring of the lower part of the panel containing the various tag strips and a small circuit board with a couple of relays (extra switches for the diamond crossing polarity and some signal interlocking), diodes to generate half wave rectified supply to the Tortoise point motors and bridge rectifiers to provide nominally 12 v DC to power the relay change-overs and the panel LED's, is almost complete.
     
    A couple of photos show the current state of play.
     

     
    An overall view of the control panel with the completed mimic diagram. The lever-frame amd track section switches previously shown have been removed from the lower section to facilitate application of the Letraset lettering.
     

     
    A view of the lower panel compartment showing the wiring - mainly on tag strips. Feeds to the layout are via multi-pin D plugs on the right hand side. Coming in on the left are 16 v AC (power to vitually everything!) and 18 v DC (for AJ uncoupling magnets) feeds and connectors for either DC or DCC controllers and the conection to the DCC power unit. Going off shot at the bottom is the bundle of wires which will conect to the switches and LED's on the panel facia.
    The coil of white wires are for the bell code ringer circuit.
    Top centre is one of a pair of 3 amp thermal trips in the feeds to the track sections (but not yet conected - hence the coils of blue wire adjacent). I've heard tales of major problems resulting from track short circuits recking controllers, melting loco wheels, etc., especially with DCC giving up to 10 amps, so hopefully these trips will help avoid that.
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