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Fen End Pit

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  1. Fen End Pit
    I've been a bit busy fiddling with dodgy electronics recently but haven't produced anything worth adding to the blog (yet). However I have also found time to build another Dave Bradwell brake van chassis so thought folks might like to see a picture. On the left is the completed one from last year, on the right the one I've just finished. I decided to do a slightly different version of van, this time with the shortened foot boards. These kits really are enjoyable to put together, a bit fiddly in places but well designed and engineered.
     

     
    Work has now started on a PDK models D16/3, so far this kit looks pretty good, some of the design is somewhat 'old school' (no option for compensation/springing) but it looks like it should be quite fun to build. Progress so far has been limited to putting together a High Level gearbox and making a start cutting slots for horn blocks in the frames. The frame spacers in the kit labeled EM/P4 are only 12.5mm wide so these have been discarded in favour of some from Perseverance which are a gnats under 15mm. For now they are just sitting in place held by the friction from the spacing gauges.
     

     
    I had a read through the CLAG website on continuous springy beams but when I drew up the ideal arrangement of fulcrums it became clear that the curvy nature of the foot plate and the size of the wheels meant the fulcrums at the ends of the chassis would actually have to be above the height of the footplate. I think I'm going to try and use a similar under-slung springing arrangement to Bradwell's J39 chassis kit. I'll make some kind of keeper plate for the wheels which includes the cosmetic springs from the frame etch and also some points to secure the functional spring wire to.
     
    Unless you have any better ideas....
     
    David
  2. Fen End Pit
    I've been playing in TurboCad today, revising my plans to fit the model of Ebridge Mill I've been making. The result has been a slight simplification of the siding to the mill, I decided it looked just too squashed with multiple sidings. Also I've managed to get more space between the two yard sidings so that you can actually get a lorry between the sidings to load/unload. The river has a slight difference in that there is now a cut from the river, under the lane with the level crossing (slightly hub backed bridge?) to form a mill leet. Between the railway and the leet there is space of a reasonable size pub.
     

     
    I'm quite pleased with the way this is coming together. I have worked out the best way of jumping between Templot and TurboCad now. I use the option in Templot to save a group of templates as a DXF, I then import this into TurboCad and immediately make it into a group. This means that I can easily manipulate the drawing and go and change part of the track layout without having a lot of hassle when I then bounce between applications.
     
    David
  3. Fen End Pit
    Having started a discussion on laser cutting on a thread in the 3D Printing, Laser Cutting and CAD group (Thanks to AndyY for adding the laser cutting bit!) I'll continue to post some of what I'm doing here just too.
     
    One of the things that is concerning me is how to make the corners of building. Some people are trying interlaced brickwork and I'll probably try butt joining some ABS as well but one thing I wanted to try was to mitre the corners. I had trying to sand anything accurately so I'm going to try and cut the angle on the laser cutter. To do this I'll need to hold the wall at 45 degrees so needed to make a giant jig. This was also a chance to see just what the cutter could do.
     
    So armed with some 3mm MDF I drew out some pieces which should slot together. The first attempt was a spectacular failure as I failed to follow my own notes on focusing the laser and then used the speed suggested in the machines manual for 3mm ply. This was way too slow (cutting speed 10, laser 100%) leaving a burning trail of destruction in the laser's wake. Moral of the story is to always try some test cuts with your new material before trying for a proper cut. Second attempt couldn't have been better (cutting speed 40, laser 100%), the laser sliced through the MDF and the parts just held together by friction as I lifted the sheet out of the machine.
     

     
    The resulting pieces just slotted together perfectly with no slop and a formed the shape perfectly. The 45 degree slope has lines engraved at 10mm intervals to aid alignment. The theory is that I can attach a wall to the jig with double sided tape and then cut along the edge to give a 45 degree mitre. Whether it will work remains to be seen but it seems worth a try.
     

     
    At the weekend I also drew up a little goods office based on some drawings in the GERS journal. I'm going to use this as a 'test card' over the next few months, trying different materials and methods while I learn. This was test one straight off the machine in 3mm MDF. (Cut speed 35, laser 20% for mortar, 100% for cut)
     

  4. Fen End Pit
    With the hiatus caused by test building of a new MERG DCC Booster and the preparation for Ally Pally out of the way, (thanks everyone for the nice comments on the London Festival of Model Railways thread) I got back to the main matter in hand, finishing the engineers' possession on Empire Basin and getting back to being able to run trains around again.
     
    Having made the fiddleyard move up and down the next step is making it stay in one place. Until I have a way of accurately holding it at a particular level there isn't much point trying to align tracks etc.
     
    My first attempt was much too wimpy, I didn't use thick enough brass rod for the bolt and the bolts holding the lock onto the vertical section were way to small.
     

     
    Attempt two used three telescopic sections of K&S tube, a section of the aluminium L to hold a servo and four M4 bolts, altogether much better engineered.
     

     
    The theory goes that I want the servo to be able to push/pull the bolt in and out. The servo claims 6Kg/cm of torque and I should have the pivot at about 1cm from the centre of the servo head. I'm hoping that with the yard effectively counter-balanced that will be enough.
     
    The other problem I had was that the horizontal shelves were slightly sagging at the front. This was making the front of the shelf about 2mm lower than the rear. To be honest I think the plastic 'easi-rec' inserts were of the cheap and cheerful variety and had a bit too much flex in them. I've now fitted some 2" angled mending plates to the sides bolted through the aluminium with M4 bolts. I marked the holes and then drilled through the square section tube to hold the shelves level. Hopefully now they won't go anywhere.
     
    So now I have to make the second proper bolt. It is a bit late for cutting aluminium section in the garage now, particularly as some of my neighbours have got a new baby! I don't think they'd appreciate the noise.
     
    David
  5. Fen End Pit
    That's Alexandra Palace and the London Festival of Model Railways next weekend.
     
    So, time to take Fen End Pit out of the cupboard under the stairs where it resides and do a few 'pre-fight checks'. Fortunately the whole layout goes up in our back room with the kind permission of the domestic authorities.
     

     
    A quick bit of scenic work with a hoover, removing the spiders, was followed up with a new coat of paint on the backscene and on the facia panel. The work then turned to the stock, fixing a couple of broken couplings and adjusting others so that hopefully everything will couple and uncouple correctly.
     
    A couple of pictures for you.
     

     
    A Simplex passes the refueling facilities with a short train of skips.
     

     
    The Lister hauls a fuel train ready to fuel up the dragline with diesel for the hard weekend's work ahead.
     
    Come and say hello at Ally Pally. It is always good to say 'hi' to other RMwebbers. We are 'backing on' to Liverpool Lime Street which I'm very much looking forward to seeing.
     
    David
  6. Fen End Pit
    A long time ago in a galaxy far, far away, I built a Wills N7 kit. The chassis was built using the etches for the kit, now sold by South East Finecast. The original chassis had the 'posh' hornblocks from Gibson (I think) which were the lost wax casting with a tiny springs pushing down on the bearing with a bolt through the top of the hornblock to locate the spring and set the ride height.
     
    All of this worked fine until you took into account the sheer weight of the white metal body. The body casting ment that the bearings were always running on the ends of the bolts and frankly the springs would do nothing except perhaps help a wheel drop down into a dip in the track. The net result was a very 'hard' riding loco which tended to clack a bit, most probably because when I had jigged the chassis up with the coupling rods for a start the bearings would have been set in the middle of their travel and now they were right at the top of the travel. All it takes is for one horn guide to not be exactly verticle and you get a tight spot.
     
    The result was a chassis that ran perfectly until you put the body on.
     
    So eventually something had to be done and, with progress on the other locos finished and the work on the layout not being exactly transportable to a Friday evening meeting, out came the N7 for another look.
     
    Clearly I needed a way to get more springing and to actually carry the loco's weight on the springs rather than as 'unsprung' weight. The thinking on springing seems to have moved in favour of 'continuous springy beams' CSB (the details are so involved that the CLAG website and Scalefour Society forum have pages and threads which can cure any level of insomlia). The simple theory seems to be to use handrail knobs to provide pivots for a continuous wire along each side of the chassis. Then use some mechanism to spring the moving bearing vertically from this wire, for example an etch from the back of the bearing or even another handrail knob drilled into the top of the bearing. The idea is that you can then thread a wire through the whole lot and it springs.
     
    The clever bit is calculating were the pivots need to go and for this purpose there is a fiendish spreadsheet on the CLAG website. The idea is you put in the wheel centres of the axles and then adjust the pivot points relative to these axles until the spreadsheet calculates the weight on each axle to the the same. Obviously the spreadsheet produces a figure accurate to more divisions of millimetres than I can drill, but it gives you a good idea where to aim for!
     
    Retrofitting onto the N7 was a bit difficult as I didn't want to have to take the wheels of the axles and requarter them etc. This meant that I really didn't want to have to either thread anything around the axle or apply heat the bearings which would probably make the wheels melt! In the end I decided to solder a long hand rail knob to a little 3mm square of brass and then thread the knob through the hole in the hornguide previously used by the height setting bolt. This arrangement is then threaded onto the CSB. Amazingly the result works and the loco is now much smoother as it moves along the track with all the weight of the white metal body 'sprung'. You can tell this is the case as there is still about 1mm deflection if you press down on the chimney where previously it was 'solid'. All this was made much easier as the chassis still had my original builders marks where I had marked up each bearing with the corresponding horn block. This meant that I knew I could get the bearing and wheels back in the same way around as they came out.
     
    Hopefully the pictures will show you what I've been talking about. I've got a bit to do into terms of getting the loco finished still, it needs the brakes back on, a cab floor and backhead and some weathering as a way of hiding the somewhat iffy lining... And no this isn't going to the the N7 that lasted as station pilot at Liverpool St fully lined out with an immaculate paint finish.
     
    David
     


  7. Fen End Pit
    I've managed to build the platform starter for the Up line following the description of making a tubular post signal in Mick Nicholson's Constructing and Operating Semaphore Signals (Booklaw publications 1999) I'm pretty pleased with it, particularly the coloured 'Crystal Klear' for the lenses. It still needs the lamp fitting which is why you can see the colours from the rear. Operation is via a servo controlled using a MERG servo4 card (which also gives me bounce).
     

     
    Having positioned the signal I got to think about the starter on the down line. This is on the inside of the curve and would actually be positioned off scene as the platform curves around to the left in the photo below. As such it would probably have had a sky arm so that it would have been visible above the canopy for an approaching train or, and this is the fun bit, could well have had a repeater signal, probably located almost opposite the signal box just in front of the driver in this picture.
     

     
    I seem to remember an article or drawing about constructing a repeater signal, can anyone remember where?
     
    thanks
    David Barham
  8. Fen End Pit
    Back from the summer holidays and a small gathering on Friday evening allowed for what are pretty much the final bits of brass to be put on the D16/3. First to go on were the front guard irons and then the brakes on the tender. I had some fun because of the earlier issues with the folding of the internal tender chassis which was slightly on the dink owing to the 1/4 etching rather than 1/2 etching of the components which made folding it up damn near impossible. in the end I had to enlarge some of the holes so that the hangers would actually be horizontal across the chassis. I'm quite pleased with the result.
     

     
    I also made up a small plate to fit between the frames and put some representation of piston rods and valve gear into the otherwise empty space. I only put on it what would have been above the level of the foot plate so you have the lifting cranks for the valve gear and a representation of the slide bars. It isn't much but is does hide the otherwise obvious 8BA nut.
     

     
    The addition of brakes didn't result in the whole thing locking up or short circuiting so we are inching closer to the paint shops.
     
    David
  9. Fen End Pit
    Last night, while out of our little group, I fitted the brakes to the locomotive chassis . The etchings were fairly basic so I added a representation of the bolt holding the brake block on by drilling each brake block and soldering a length of .45 wire through the hole. Also, while the kit included a etching for the rigging which joined the brake hangers together, it didn't include anything to represent the pull rods from under the cab. I ended up using some scrap etch from the chassis to at least but something in the right place. It took most of the evening but the result was 4 brakes and the rigging fitted.
     
    Returning home (late) I put the loco on the track and much to my surprise/relief the whole lot did not short out.
     
    David
     

  10. Fen End Pit
    A Bank Holiday gave the perfect excuse for some more soldering, but I'm running out of bits to solder on the body now. I put on the pipes along either side of the valancing, complete with little joints. Also got on the lamp irons and buffers.
     
    The chassis now fits, but for the wrong wheels in the pony truck.
     

     

     
    Still left are the guard irons on the front bufferbeam and the various bits of frame underneath the footplate but I'm waiting on getting the pony truck right before I do this. So I think I might have to get some Araldite out tomorrow and start sticking bits on.
     
    Anything to delay trying to roll a flare on the tender!
     
    David
  11. Fen End Pit
    Last night, with the help of the Chief Mechanical Engineer of our little group, I got the wheels on the chassis of my D16/3. Once again the GW wheel press proved its worth in getting everything quartered though we had a bit of fun getting the first set on the axle as the holes in the wheels were particularly tight. So points to remember with Alan Gibson wheels:-
    1) always make sure the rear boss on the wheel won't foul the counter sunk end of the crank pin, you often need to cut the plastic back a shade.
    2) shamfer the ends of the axles
    3) just tickle the back of the axle hole of the wheel with a large drill bit to put a slight shamfer on that too
    4) apply spit!
     
    Now I have had it pointed out that the Gibson wheels are not really curvaceous enough for a Claud and looking at the photographs I'd agree that they look a little 'thin'. However despite the best brains in East Cambridgeshire scratching their collective heads we can't really come up with a way to do much about it. The best I might hope to achieve would be to stick an overlay of about 10-20thou plasticard onto the middle of the wheel and crankpin boss and try to fatten up the outside of the wheel centre. Trying to do anything about the spokes seems like a non-starter to me.
     
    I'm afraid I can't wait for Ultrascale (if they did them) and can't afford Exactoscale so will have to live with the Gibsons.
     

     
    Now the front pony truck is obviously still fitted with an old pair of wagon wheels just to see if it would spring. More discussion last night centred on how to spring it/hold in place/make sure it gives a bit of sideways force as it goes around corners to keep the loco in the right direction. I likes the pivoted beam idea from the kit and copied an idea from said CME and decided to use an old sprung buffer as the pivot. The idea is that this will spring up against the bottom of the footplate but be able to move side-to-side on the end of the pivoting beam. I should be able to control the level of side play with some wire applying sideways force to the beam. This is a work in progress we'll see where it takes us.
     

     
    Having made the chassis roll I now need to refit the motor and try it under power, I'll let you know how it goes.
     
    David
  12. Fen End Pit
    After an all to brief week in the Lakes (traveling north via Scaleforum North in Wakefield, obviously) I returned to work and the workbench this week.
     
    First task was to build a combined keeper plate and spring assembly for the D16/3 chassis. Having cut the cosmetic springs off the bottom of the frames as I was fitting the hornguides I've now used some strips of nickel silver and some extra frame spaces to make a keeper plate that stops the axles falling out, it will ultimately be held on to the main part of the chassis by the body mounting screws.
     

     
    I've also arranged springing on the axle-boxes using roughly the same method as Dave Bradwell's J39 chassis kit. A length of spring steel wire is held on the keeper plate and on a small tab soldered to the bottom of the axle-box.
     

     
    Getting dangerously close to needing some wheels, but that will have to wait for an evening when one of my esteemed friends has a GW quartering jig available, that is if they are willing to come out ever again for fear of being photographed.
     
    David
  13. Fen End Pit
    The frames have got soldered together and then I put together the coupling rods. These went together very easily, being made of two thicknesses of etch. As someone who doesn't built enough locos to justify a really expensive jig I'm doing this the old fashioned way. Using the coupling rods to position the horn blocks I've now got these soldered in. Each of the bearings has been paired to a horn block and it is important to mark each pair so you can match them together.
     

     
    At the moment things are just a little tight, but better that way than too loose at this stage.
     
    David
  14. Fen End Pit

    Shunting Signals

    By Fen End Pit,

    It is amazing what you can get done over a weekend when you don't have RMweb to distract you. Seriously though I work in IT systems management and can sympathize with Andy. These kinds of upgrades are a complete pain for all concerned and we should be grateful to Andy and the Mods for all the work they put in.
     
     
    So, the weekend was taken with fitting a pair on Conrad point motors to some ground disks. The disk was an etch of unknown original I obtained back in the days of the old Cambridge Area Group.
     

    J65 waits at the shunting signal to use the cross over between up and down line.

    Right Away
     
    David
  15. Fen End Pit

    More bouncing signals

    By Fen End Pit,

    More fun with MERG electricery. I purchased a PICKIT2 which allows you to change the software running on the PICs used by the MERG Servo4 controllers to a version called Sema4 which has the option of setting 'On' and 'Off' positions, the 'On Speed' and 'Off Speed' and then up to 3 'bounces' in each direction. The result is shown in the attached YouTube clip.
     
    http://www.youtube.com/watch?v=Un5LMUBFDM8
     
    For the technically minded I've also now upgraded the software on the MERG CBUS modules to support the 'FLIM' programming method. This means that rather than having to set what each of the inputs does using dinky dip switches I can now set the whole lot via a configuration tool on the PC. What is the point you might ask... Well it does mean that wiring up now just becomes a case of wiring an accessory (point motor, signal, magnet' to any available output on any MERG output device and then just selecting which switch or lever operates it. Changing the switch or control panel later just means making a change to the configuration via the software. I can't help thinking that if I was involved with a major club layout I'd strongly be advocating this kind of approach, it would allow different individuals to wire boards and then configure a control panel once the whole lot gets put together.
     
    David
  16. Fen End Pit

    Preparing for ExpoNG

    By Fen End Pit,

    As next Saturday Fen End Pit is off to Expo Narrow Gauge at Swanley this afternoon was spend checking and preparing the stock. Several couplings needed adjustment, lots of wheel cleaning but nothing serious in need of repair. I had realized I was one driver down so have also been trying to convert 'Larry the Lister driver' into 'Sidney the Simplex driver'
     
    I took the opportunity to take a few photographs and a short clip of the Simplex 40S with the sound chip.
     
    http://www.youtube.com/watch?v=dQ6oDwIEctU
     

     
    Having got the 40S checked I moved on to the 32/42 type.
     

     
    I also checked out the drive mechanism for the Dragline and tomorrow I expect to get the boards checked out too.
     
    Hope to see some RMWEBBER next week.
     
    David
  17. Fen End Pit
    Over the last couple of weeks I've rewheeled a Bachmann LMS 50 Brake and a BR GUV, two more additions to my parcels train. Actually it is probably going to end up as an 'Up Parcels' and 'Down Parcels' as the fiddleyard won't be long enough to hold all the stock! I did a bit of a foolish thing with the GUV, I brought one in Rail Express Parcel livery as the Maroon wasn't available and then tried to strip it and repaint it. By the time I got around to trying to line it and number it I found I could buy one in the livery I wanted for less that the cost of buying all the transfers. I have had the suggestion of repainting it from maroon into crimson as this would avoid it being lined, does anyone know of a suitable picture?
     

     
    Progress on the rebuilding of Empire continues at a pace, the other end of the layout getting the MERG CBUS treatment with a new control system installed over the weekend. This also allows for the Up Advanced Starter and shunt signal to get planted with a pair of servos underneath controlled by a MERG Servo4 board.
     

     
    Next up is a getting the rest of the ground disks working.
     
    David
  18. Fen End Pit
    An order to Modelmaster produced suitable transfers for the 16t minerals I've built up over the last few months. The plaintive requests on their website asking for people not to bother ringing them to chase order were unnecessary as delivery was 4 days!
     
    The ease of not having to put every b£$"d% number on individually is certainly a major advantage if you are like me and don't really mind if the number isn't exactly correct. I had no problems getting them to float to the position I needed and then stay there.
     

     
    Also I thought I'd put up a picture of my Airfix brake-van based on a Dave Bradwell chassis. This was great fun to build and I'm really pleased with how it looks and runs.
     

     
    Back on the subject of the GUV I'm really confused by humbrol's acrylic paint range. I get on well with these for spraying so was looking for the right colour for BR Maroon coaches. I'm presuming that RC423 Carmine is the 'blood' in 'blood and custard'. Is it RC403 described as Crimson Lake I need?
     
    David
  19. Fen End Pit
    It has been a frustrating few weeks on the scalefour roundy-roundy. A major part of the design is the track running from the high-level viaduct down to the quayside. This was all laid, and generally locomotives could go up and down it, however getting a train to go either up or down was causing problems.
     
    As there is a reversal on the way down you have to deal with the locomotive being at the 'up hill' end for half of the journey. This leads to two problems, firstly when you shunt the wagons going up you get buffer lock on the tight curve and secondly as you shunt on the way down you risk things uncoupling.
     
    Alex Jacksons can be particularly fussy over changes in gradient and I had a distinct 'kip' at the top of the hill. This evening was spent with solder iron, files, screw driver, drill, hammer etc and evening out the hump.
     
    The result is that I can now get wagons down the hill under control rather than having them hurtle down the slope!
     

     
    This shows the top of the hill and the gradient is pretty clear.
     

     
    The destination in the bottom quayside yard.
     
    David
  20. Fen End Pit
    I've spent the evening fitting the various pipes to the buffer beam on the Class 15. Quite fiddly, but worthwhile. Having thinned down the sandboxes they are on too. I've opted for a freight headcode and think adding the disks to the nose really brings the loco to life.
     
    Now I must get around to ordering a chip, but every time I think about it during the day somebody asks me to do something at work!
     

     
    I think I'm going to trim back the coupling holder to fit an Alex Jackson hook in. It shouldn't fowl the pipework. Also still to fit is a coupling hook. I'll not use the ones from the loco as these have a dangling screw link which would get in the way of the AJ.
     

     
    Now to do the other end....
     
    David
  21. Fen End Pit
    As I had to take the chassis apart to solder the brake hangers on (they were too close to the wheels for comfort) I opted to paint the chassis while everything was accessible. The frames were brush painted with some enamel primer and the a coat of Humbrol matt black, which amazingly dried matt. I then picked out the valve gear with some Humbrol gun metal to give a slightly shiny look of steel. A quick blast of acrylic railmatch 'frame dirt' has toned it down a bit.
     
    Another task completed was to stick the balance weights on the wheels and fill behind the slivers of nickel-silver with some Humbrol filler. I'm very pleased with the way these came out.
     
    I also primed and painted the underside of the tank and took the LNER off the tender.
     
    Most remarkably it still moves when I put the wheels, gears and motor back in!
     

  22. Fen End Pit
    Well the bouncing signal got painted and planted, at least temporarily. I've still got to 'matt it down' a bit and add the green spectacle glass.
     
    I've slowed the bounce down from the first attempt on the starter, the shunt signal is still a little on the fast side.
     

     
    David
     
  23. Fen End Pit
    A day off on Friday allowed time to start track building on the lower quayside area of the layout. This bit of the layout is a bit of an 'Enigma Engineering' inspired shunting puzzle, I might even resort to waybills so I can shunt different bits of the pickup goods down to the lower yard. I know one end of the section is going to be a coal yard, but I'm not sure about the other end yet, possibly a scrap yard? The intention is for this track to be inlaid, so copper-clad sleepers and lots of check/guard rails are the order of the day. To make life more fun I decided to add a three-way into the plan. I'd never built one before and was very glad of the guidance in the Scalefour society digest on which rail to lay in what order. Wiring also confused the heck out of me as the point I built was the opposite way around to the wiring diagram and i had great trouble reversing the diagram, and working out which rail was which from underneath the baseboard for wiring.
     

    Please excuse the temporary bit of wire to jump the rails together!
     

    The points are operated by cranks connected to the SPDT switch that changes the polarity of the frog, or frogs in the case of the 3-way.
  24. Fen End Pit
    Last night and tonight I made up some Brassmasters etched windows for the warehouse. I think these make quite a difference. Next step is probably going to be working out how to do the roof. One the one hand I fancy doing something with a pitched (maybe hipped) roof, but on the other I'm concerned how that might look given that the backscene means there would be no straight lines.
     
    I think this calls for some cereal packet mock-ups!
     
    David
     

     

  25. Fen End Pit

    Bradwell Brake

    By Fen End Pit,

    One of the most enjoyable bits of stock construction over the last year was this Dave Bradwell Brakevan chassis kit. Paired with the body of an airfix/Dapol kit I was very pleased with the result. The chassis kit is ??16 and was very well designed and etched. The etch looked fiendish at first glance but I found the step-by-step instructions very good. While it took a lot of time and concentration to put together it was extremely satisfying.
     

     
    I suspect there might be a Dave Bradwell J39 chassis coming for Christmas and I'm looking forward to building that.
     
    David
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