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Hornby Flying Scotsman NRM Fitting Guide


This paper describes one approach to fitting a variety of equipment to a loco. The example uses a Hornby Flying Scotsman NRM model, R2441, and the kit fitted is quite extensive, but many of the techniques are applicable to other models too.

Please note that YouChoos cannot be held liable for any mistakes or failures that occur due to an install done by yourself, and you should expect to make mistakes (hopefully small, hideable ones) the first time you try it! YouChoos is able to supply the components required for a 'kit' so that you can perform the install yourself, or you can have YouChoos perform the installation for you as a service. YouChoos does not list specific kits for sale, but almost any loco with many combinations of kit are possible, so please send me an e-mail to discuss specific requirements.

The Locomotive Model

As mentioned, the example here will use a Hornby R2441 model, which is a Super-Detail Flying Scotsman, in NRM guise. This is a top-end model to start with, and as such has more delicate parts than some of the cheaper models. Whilst this means that you have to be particularly careful with the install, it also means that the eventual result can potentially be stunning.

Before you do anything, you should always test that the loco runs properly as it is to begin with. Correct any issues with movement, which may involve various adjustments, oiling, and cleaning of the pick-up wheels. There is no point in enhancing a poor-running loco!

Kit Parts (supplied by YouChoos)

  • CT SL51-4
  • CT sugar-cube speaker
  • Seuthe #22 smoke unit & oil
  • Firebox light - wired and resistor pre-fitted
  • Cab light - wired
  • Crew - Bachmann OO driver & fireman
  • Internal tender light - wired and resistor pre-fitted
  • Buffer-beam lamps - vertical mount, 2x yellow, 1x red (yellow lamps have a white negative wire, red lamps have a yellow negative wire)
  • Boiler door lamp - horizontal mount, 1x yellow
  • Tender lamp - horizontal mount, 1x yellow
  • Additional tender lamp / coach light indicator - horizontal mount, 1x red
  • Coach connection - wired and colour-coded
  • Loco-to-tender connection - wired and colour-coded
  • Additional decoder wire - variety of colours
  • Sticky pads - for decoder and speaker mounting
  • Heatshrink - short lengths for lamp resistors + longer strip to use as required
  • Resistors - 1k (small) for use with lamps and cab light

Click the pictures below to enlarge individual items

CT SL51-4 decoder and speaker Seuthe #22 Firebox lantern pre-wired with resistor (in heat-shrink) Super-bright white LED for cab light Crew of driver and fireman - Bachmann range Internal tender light, pre-wired with resistor (in heat shrink) 2-pin Connector for tender-to-coach lighting 4-pin Connector for loco-to-tender Horizontal and Vertical mount YouChoos yellow lanterns Horizontal and Vertical mount YouChoos red lanterns Spare decoder wire, for general use during install Resistors, heat shrink and double-sided sticky pads

Suggested Tools Required

  1. Variety of small screwdrivers - both Phillips and flat-head (for disassembly/reassembly)
  2. Mini-files (for siting of sockets on tender)
  3. Soldering iron (fine tip ideal)
  4. Scissors / wire-cutters
  5. Super-glue
  6. 2-part Epoxy glue for smoke unit fixing (needs to be type capable of taking around 250'C)
  7. Electrical tape
  8. Fine paint brush
  9. Paint - acrylic recommended (for touch up of lamps and coating of visible wires)
  10. Small hand-drill with a variety of miniature drill bits
  11. Spinner or micro-spanner (for removing/refitting speedo nut from wheel assembly)
  12. Also useful: Roto-tool (e.g. Dremel) with small sanding bit (for recessing firebox glow light)
  13. A steady pair of (clean) hands
  14. Patience
  15. Reasonable eye sight

Click the pictures below to enlarge individual items

Various mini screwdrivers, super-glue, and mini drills Soldering iron Variety of mini files E-Tape, Scissors, Nut Spinner, Paint Brush, Pliers 2-part Epoxy glue (high temperature rating) for smoke unit installation Roto-tool and sanding bits

Fitting Steps for Tender

...sorry, no photos available for this - only descriptions...

  1. Disassemble tender... Remove 2 screws on left and right of underside of tender using a small Phillips screwdriver. Carefully lift tender shell away from chassis and keep chassis somewhere safe (you wont be needing that again until you reassemble the tender). It is a good idea to organise the 'bits' that you take off in a specific order so that you know to put them back again in reverse order later - especially if there are a number of similar-looking components, such as a variety of screws of slightly different sizes! Yes, I know, this sounds like common sense, but it is amazing how easy it is to get muddled up!
  2. Fit 4-pin socket for loco-to-tender connection... Choose a suitable location for fitting the 4-pin socket on the front of the tender. It is best to keep it horizontal as this reduces the visibility of it from the side, so it will look better than a vertically mounted socket. The socket needs to be high enough that it will not interfere/catch on the foot plate or anything else on the loco, and set deep enough that the loco can still comfortably turn corners. The socket is going to be almost flush with the hole's entrance, so check that the location you have chosen has enough room behind it so that the back of the socket, and the wiring can fit in, even with the tender chassis reattached. Ok, so don't be scared, but you are about to do the first bit of real butchering to your model! Measure up the hole required for the socket and start by using a small hand-drill to put in guide holes. You will probably be able to put in 3 or 4 guide holes in a horizontal line using a 1.5mm drill bit, for example. You may be able to keep changing the angle of the drill so that the holes join up. Next, carefully use some small square or flat files to enlarge the hole so that the socket just slides in neatly (should ideally be a fairly tight fit). Ensure that the socket is fitted with the white dot on the top (BLUE-ended wire - function common positive - should always follow the LEFT side of the loco). Slide the socket in so that you can just still see the white dot on the top and use a small amount of super-glue to fit it from INSIDE the tender body. Never glue from the outside - it will make horrid stains that you'll have to file and paint over later! You will probably only be able to apply a small amount of glue to 3 edges of the socket - don't worry - that is plenty to hold it.
  3. Fit 2-pin socket for coach light (if required)... If you intend to have coach lighting fitted, then this is a good time to fit the 2-pin socket on the back of the tender. Follow a very similar approach to how you fitted the 4-pin socket above. Yes - the tender has both sockets! Position the 2-pin socket centrally somewhere on the back of the tender - probably just below half-way up the back, so that it is out of the way of the tender chassis internally, and also out of the way of any lamps that you may fit on the back. Again, orient it horizontally and only allow a tiny bit of the socket to pertrude (so you can just see the white dot). If your tender has a corridor tender then you can let it protrude quite a bit further, which is a good idea anyway as it will be easier to fit/unfit any plug from the coaches. Remember - BLUE-ended wire on the LEFT of the loco, which is the common positive for the function outputs. Don't connect any wires between sockets yet - we'll do all of the connecting up once the kit is installed in the tender.
  4. Fit internal red tender light (F0 - forward motion)... The NRM Flying Scotsman model has a clear round window at the top on the right of the tender, so rather than fit an external lamp we will instead fit an internal red LED inside the tender body just behind this window. Our kit comes with a suitably large flat-topped LED already filed down to (hopefully) fit snuggly behind this window, and pre-painted in black around the sides to prevent too much light from escaping from the sides. Position this LED behind the window (right up to it) and use some glue to fix it in place. Try to glue around the sides of the LED rather than over the lens, as glue on the lens tends to dry visibly on the window. Gel super-glue is ideal for this - beware of using liquid super-glue as this has a habit of running through the join in the top of the tender which is then visible from the outside! This red lamp is intended to use for the F0 function (directional lighting) and will be on when the loco is moving forwards (ultimately this goes to the white wire on the decoder).
  5. Fit yellow lamp to tender (F0 - reverse motion)... When the loco is moving in reverse direction, it is nice to have a yellow lamp on the back of the tender to indicate that this is the case. Again, this will be controlled by the F0 function (ultimately the yellow wire of the decoder). Choose where you would like the yellow lamp positioned on the back of the tender (you could even have multiple!). Choose a horizontal-mount yellow lamp (wires come out the back and travel horizontally, and lower wire will be white). Measure up the lamp's legs and drill small holes using a hand-drill in an appropriate position (probably above a lamp iron). Each YouChoos lamp is hand-finished, so the legs may differ in thickness depending upon how neat my soldering was on that occasion! Do not force the legs through your drilled holes, or the wires may break off and you'll have to resolder them - enlarge the holes slightly instead if you need to. It should be possible to put both holes behind where the lamp will go so that they are completely hidden once fitted. Once it is threaded through, it is often worth testing that the LED is working ok by connecting to a power supply - remember to put a resistor before the positive lead though, or you'll fry the LED instantly! All YouChoos LEDs have their positive lead at the top and will be wired with either a BLUE or a BLACK wire. Once you are happy with the lamp's position, hold it gently in place from the outside and apply a small amount of super-glue from the inside. Liquid super-glue is best here, although be sparing with it as it may run through to the outside of the tender body. Once the super-glue has dried it can be useful to apply a little thicker glue (Bostick/UHU etc.) just to give it a bit more strength). Trim the LED wires as you see fit and attach a resistor to the positive (BLUE/BLACK) wire. I tend to cut the positive wire quite short (say, 2-3 cm) before attaching the resistor. You can then use the cut-off part of the BLUE/BLACK wire on the other side of the resistor, and add a small tube of heat-shrink around the resistor too.
  6. Fit additional red tender lamp (if required) to indicate coach lighting (F2 - coach lighting)... If you want to add a 'indicator' lamp to the back of the tender to show when the coach-lighting function is activated, this is best done with a red horizontally-mounted lamp (lower wire is yellow) - perhaps high-up in the centre of the back of the tender. This feature will mean that you can still enjoy the F2 function even without lit-coaches attached! Follow a similar approach to fit this lamp as you did for the rear yellow lamp above.
  7. Connect tender wiring... Once the above items are in, and the glue is dried (you may have to wait a few hours if you used Gel super-glue, or a thicker glue), you can connect all the wires together. Join the blue-ended wire of the 4-pin connector to the blue-ended wire of the 2-pin connector, and also to the positive wires of any LEDs that are fitted (usually a BLUE or BLACK wire). Double-check that ALL LEDs have RESISTORS FITTED to their positive leads - if you don't you'll blow the LEDs, or worse, you might permanently damage the function output circuits of the decoder later on. You should therefore have quite a few +ve wires to solder together. Cut a small length of heat-shrink and use this to protect the connection once it is soldered, or alternatively use a tiny piece of electrical tape to cover the exposed wires. Next, we will connect the 'forward motion' lamp(s) to the WHITE wire of the 4-pin connector. This is probably just the large red LED that you fitted behind the tender window. Next, join the 'reverse motion' lamp(s) to the YELLOW wire of the 4-pin connector. This will probably be a single yellow lamp on the tender. Finally, connect the coach lighting wire, which will be the final wire from the 4-pin connector (probably GREEN) to the remaining wire of the 2-pin socket, and also to the YELLOW lead from any coach-light indicator lamp that you may have fitted to the tender. Heat-shrink all the exposed wires and curl the floating mass of wires into some sort of neat shape (!), using electrical tape to secure it to the roof of the tender, so that it is all out of the way of the chassis when you come to re-assemble in a moment.
  8. Test tender features... Before you put the lid back on the tender, it would be a good idea to test that the lights all work as expected. You can do this using the 4-pin plug and connecting the blue-ended wire of that to the positive output of a DC power supply, then try each of the other 3 wires to test the 3 functions in turn to check that the lights all come on. This is also a very good opportunity to touch up any paint on the lamps that you may have accidentally scraped off during the install - it is almost inevitable that a little glimmer of light is emmitted from some unwanted part of a lamp somewhere! Use acrylic paint using a very fine paint brush in an appropriate colour until you are happy that the light only shines where it is supposed to.
  9. Re-assemble tender... Carefully put the tender body back on the chassis making sure you do not force it, as there are lots of delicate parts on this tender. Replace the 2 screws underneath to secure it in place - not too tight, as it is just plastic that they are threaded into. Well done - you've just completed a big part of the project, and it wasn't too bad was it?! The loco will be a lot more involved, but at least you have made good progress, and what you have just done will be invaluable experience for later.

Fitting Steps for Loco Chassis

...sorry, again no photos available for this - only descriptions...

  1. Handling the loco... Ok, this is where you really need to start getting careful with how you handle things! The loco is far more fragile and sensitive than the tender. In fact, the R2441 model is one of the most sensitive models I've come across! Pay particular attention to how you handle the detail parts such as pipes, smoke deflectors etc., and be equally careful when going anywhere near the wheels, pistons and cylinder blocks - a small change in shape to a piston can easily cause poor or jerky motion when it is all put together again. However, if you maintain an awareness of what you are touching and where pressure is being applied then you shouldn't have a problem!
  2. Removing the speedo... Like many of the Hornby Super-Detail models, the R2441 has a speedo attachment to one of the rear driving wheels. This must be removed before you attempt to take the body off the chassis. Before touching it, make a note of how the speedo is located and its orientation. It usually has the pivot right in the centre of the rear with the lower arm going forwards. Maybe even take a digital photo of yours before you start work. An incorrectly fitted speedo will almost certainly cause jerky movement. Lay the loco carefully on its side on a softish surface and Use a 'spinner' or a suitably small spanner to remove this tiny bolt. Do this very gently, holding the wheel steady if necessary. The bolt goes through the speedo arm and also a small metal spacer ring. Make a note of the order that it is set so that you can correctly put it back again later. Once the speedo arm is out of the way, reattach everything except the speedo arm in the correct sequence. There should be no spare parts from this - it is simply case of taking the speedo arm off the wheel. The speedo arm will now float free so always be aware of where it is so that it does not get bent of snapped off. If you find the speedo a pain, you can always remove it altogether!
  3. Separate loco body from chassis... Locate the large screw underneath the loco's front bogie and use a flat-head screwdriver to remove it. Keep the screw somewhere safe for reassembly at the end. You do NOT need to remove the bogie. With the screw removed you should be able to gently (ever so gently) separate the body of the loco from the chassis. Start at the front, holding the loco in its proper upright position. The front should drop down fairly easily (perhaps with a little encouragement by levering it out with a flat-head screwdriver from the front. Once the front has dropped out a little you should be able to pull the chassis forward to release it at the rear. It is held in place just under the cab by a couple of small metal arms. Once these are out you should drop the chassis vertically down so that it is completely separated from the body. Put the body somewhere secure for a while as we are going to fit the basic DCC components onto the chassis first.
  4. Remove DCC-ready components... As with many steam loco models, there is very little space in the loco body, so it is useful to free-up as much as you can before you begin putting anything new in. It may be possible to plug a DCC decoder directly into the provided 8-pin socket, but then you'll have to find somewhere suitable to put the speaker and the additional wiring that will ensue. Therefore I would recommend that you take out the 8-pin DCC socket, as this is the perfect place for the little CT sugar-cube speaker to sit. So, remove the screws that hold the DCC socket in place, and remove any plastic mounting foot that you find underneath. Cut the wires that go to the DCC socket, remembering which ones were paired together (these are the pickup wires from the track). Sometimes I remove the small capacitor which sits across the terminals of the motor too - this frees up even more space. The capacitor is used to supress interference with TVs, although I've yet to actually see this effect in reality, so I tend to just remove it! If you are going to remove it, you might as well remove both wires from the motor altogether, and solder the motor outputs of the decoder directly onto the motor (we'll come to that in a moment).
  5. Wire the decoder for motor control... It is always good to keep the length of wires to a minimum where possible, and a good opporunity to do this is with the wires from the decoder to the track and the motor. Decide on a suitable location for the decoder, and trim the RED/BLACK (track) and ORANGLE/GREY (motor) wires to an appropriate length (probably about half the length they were originally). There are 2 potential locations in the R2441 model: behind the motor, standing almost vertical against the end of the motor assembly; or directly on the top in front of the motor. Either will work, but you'll probably find the most room if you fit it on the top in front of the motor. Solder the RED decoder wire to one pair of track wires, and the BLACK decoder wire to the other pair of track wires. Hornby usually make one of the track pick-up wires RED anyway, so it is a good idea to connect your RED decoder wire to the pair that contains the RED pick-up wire, although it doesn't really matter which way around you do it for DCC. Solder the GREY decoder wire to the top of the motor, and the ORANGE decoder wire to the bottom of the motor. Note that you may need to switch the GREY and ORANGE wires around, as different motors vary from model to model (even different R2441 models can vary - good old Hornby, great consistency!)
  6. Test motion and sound... Before you actually mount the decoder anywhere, this is a great opportunity to test some basic functions of the install - motor control and sound. Therefore put the chassis on a DCC-powered track and put the tender on the back (this is useful to get the extra pick-up contacts, and will also check that you paired the track wires up correctly). Make absolutely certain that there are no loose wire ends from the decoder touching anything else metal, or each other, and ensure that the decoder and the speaker themselves are not in danger of shorting on anything either. Switch your DCC controller on and try some basic motion to begin with. YouChoos decoders are always shipped on a DCC address of 3, unless specified otherwise. If the motion appears to be reversed, you'll need to swap the ORANGE and GREY wires around and try again. Also try the sound out - it should be fully functional (F1 normally switches the main running sounds on/off, and other functions will sound the auxillary effects). Beware that the speaker will 'walk' when the sound is on - this is just vibrations, so probably best to hold the speaker while you are doing this!
  7. Fit decoder...Use a large double-sided sticky pad to mount the decoder. Remove one side of the sticky pad backing and stick the pad onto one side of the decoder lengthways. Try out some precise position first, before removing the other side of the sticky pad backing, then when you are completely happy with the location, stick it onto the chassis. You should consider if any short circuits are possible, and either ensure that the stick pad itself protects the decoder, or add small pieces of eletrical tape onto the chassis in suspect locations. Think about which direction you want the wires to initially travel - forwards or backwards? In general I find backwards is best, although it is possible to make it work either way.
  8. Fit speaker... Use another double-sided sticky pad to mount the speaker onto the chassis where the DCC socket used to be. One of the long sticky pads is best here too. Stick the top of the speaker (the resonator side, NOT the metal side!) to the sticky pad and stick this firmly onto the chassis with the BROWN wires pointing backwards. Make the speaker as central as possible, or you may have trouble refitting the body later on.
  9. Tidy wires... you may like to take this opportunity to tidy the BROWN speaker wires and the BLACK/RED/ORANGE/GREY track/motor wires using some thin strips of electrical tape. Don't use too much though, as you'll have more wires to tidy up later anyway, once the functions are all connected. It is always a good idea to test the chassis (with tender attached) again at this stage, ensuring that you avoid shorts the remaining trailing function wires.

Fitting Steps for Loco Body

  1. Handling the loco body... Ok, so you've done the easy bits! This is where you truly have to watch how you handle things, avoiding the fragile bits, religiously cleaning your fingers after using glue etc. I have to say this, as it is all too easy to take short-cuts and want to just press on with the job. Don't rush it, be patient and ever aware!
  2. Fit firebox glow light (F4)... Let's start the body install with one of the easy bits - the firebox glow light. Note the shape of the orange LED - you'll be making a hole just the right size to fit the dome into so see if you can find a small drill bit for your hand-drill that it just right for it. From the driver's side in the cab, make a pilot hole dead-centre in the firebox door using an even smaller drill bit. A steady hand is required here to ensure that you do not scratch the cab interior. Once you are happy with the position of the pilot hole, enlarge it to the right size for the LED dome. You'll notice that the firebox door is actually quite a thick peice of plastic, and the dome does not poke through very far. Therefore it is a good idea to file out a bit of a recess from inside the loco shell so that the LED sits further in. The will have the effect of giving the light more visibilty but will also mean that the trailing legs and wires behind it take up less space inside the shell - always a good thing! I find it easiest to use by Dremel with a small sanding bit to make this recess, although you do need to watch where the spinning bits are. Once you are happy with the depth of the recess, test the fitting and ensure that any lose debris is removed from the hole. To fix the LED in place, ensure that the legs/wires are pointing upwards into the shell and hold in place with your fingers while you apply a little super-glue with the other hand. Liquid super-glue is good for this, and as long as the fit is snug, you wont get any glue running into the cab through the hole either. Let the super-glue dry, and if you like, apply a little bit of thicker glue (shouldn't be necessary, but it might make you feel more secure about it!). It is a good idea to test each item as you go along, so use a DC power supply to try the LED out (it already has a resistor attached, so you can go direct to the supply).
  3. Fit cab light and resistor (F5)... Not all models can take a cab light, and R2441 is actually rather a tricky one to do this to, since it has sliding roof panels. You may decide not to bother fitting it if it just looks too tight. Ideally the cab light should be positioned as far fowards in the centre of the roof as possible, as it is quite a bright light and the effect is better if you tuck it right in. To fit it, drill 2 tiny holes right at the top of the cab from the inside of the loco shell (do not do it from the cab side, or you may 'miss' and never actually get the drill to go through to the inside). The holes can be very small, just big enough for the wires themselves. Insert the 2 wires through their respective holes, apply a little super-glue to the spot that you want the light at, and hold in position while you apply a little super-glue around it too. The cab roof is not flat so you may need to apply some thicker glue later to hold it in properly. Trim the positive wire (BLUE or BLACK) from the cab light and attach a resistor to it, using a short length of heat-shrink to cover the resistor and its wires. With the resistor connected you can test the cab light directly with a DC power supply.
  4. Fit smoke unit (F3)... Plastic-bodied models need plastic-friendly smoke units, such as Seuthe #22 or Seuthe #27. In fact, for model plastic models, smoke it simply not a good idea as the plastic will heat up and warp anyway - even using a #22 or #27. A rule of thumb that I use is that if your chimney is taller than 3mm then you should not fit a smoke unit. If you are feeling particularly brave then you might like to try replacing the plastic chimney with a white metal one, but do so at your own risk! The R2441 Flying Scotsman is ok for a single smoke unit though (2 are theoretically possible, as it is a double-chimney, but this generates a huge amount of heat, as well as requiring some grinding of the chassis to accomodate it, so I don't recommend it). Our example here will be a single Seuthe #22 in the front chimney. Use a round file to enlarge the hole just enough for the smoke unit to slide in (should be quite snug). Test if it fits from the top, as this is easiest. Use a gentle rotating motion with the file so that the hole remain properly circular and still centred in the original centre. Once the unit fits nicely, slide it in from inside the loco body until it is perfectly flush across the top of the chimney. If the hole is too large, then this isn't too much of a problem, but you'll need to hold it in the correct position when you put the epoxy glue on in a moment. Use something like a 5-minute epoxy glue (2-part) which you should be a very small amount of and (while holding the body upside down - possibly with a finger on the top of the chimney to keep the height perfect), apply the epoxy around the sides of the chimney where the chimney meets the body. Be careful not to apply too much - you don't want epoxy leaking out through the 2nd chimney hole (you can put some electrical tape across the 2nd hole from the inside to avoid this if you like). You must NOT coat the chimney with the epoxy as this will cause it to overheat during operation and burn out. Just apply the epoxy where the unit meets the body. A few mm depth around the join itself, then tapering away. Epoxy glue is terribly messy so be super careful to avoid getting it on your fingers, or anywhere else unwated. It is a good idea to hold the whole loco body in a piece of kitchen towel while you apply it, just to reduce the risk of sticky finger prints ending up on the shell. Either hold the smoke unit in place (with the body still upside down) until the epoxy has set hard enough not to run, and the chimney stays firmly in place. Even 5-minute epoxy takes more than 5 minutes to harden thoroughly, so I suggest that you wait a few hours before testing it. Testing is simply - the 2 wires from the smoke unit can simply be attached to a DC power supply for a few seconds. There will be a tiny amount of residual material in the unit from manufacturer that will cause it to smoke a tiny bit. Just do this to start with to satisfy yourself that it does actually work. If you want to try a few drops of smoke oil too, then that's fine. The wires pre-fitted to the smoke unit are a little short for comfort, so use a little extra decoder wire to lengthen those and place some heat-shrink around them for protection. The best direction to send the wires is one to each side of the loco - backwards is not much good because the chassis will be situation directly behind the smoke unit when reassembled. The is a fair bit of room here though, so maybe just use a little electrical tape to fix them to either side out of the way. The smoke unit can be connected either way round - there is no specific positive or negative wire.
  5. Fit boiler door lamp + resistor (F6)... Actually, I don't often fit a boiler-door lamp to the R2441 model, but it can provide a nice additional feature. Take one of the yellow horizontal-mount lamps (legs trailing out the back, wires BLACK/BLUE and WHITE) and measure up where you want it to go on the boiler door. There should be a lamp iron very close to the top on the centre, which is the obvious place. You will need to remove the lamp iron and drill 2 suitable holes vertically to accomodate the legs of the lamp. It may be necessary to place the lamp slightly lower than the lamp iron so that the holes can comfortably go through the door and inside the loco's shell. Fit it in a similar manner to how you glued the lamps on the tender. Fit a resistor to the positive wire (BLACK/BLUE) and cover both wires in their own length of heatshrink - this is necessary because these wires will be passing the smoke unit and therefore need to be well protected. You may be able to glue or tape the wires to the side of the inside of the boiler too, just to ensure that they give the smoke unit a wide berth. Test this lamp using a DC power supply when it is fixed in place.
  6. Fit buffer-beam red lamp + resistor (F0 - reverse motion)... The buffer-beam lamps are the trickiest part of the install since they require precision drilling and positioning of the lamps (so they are symmetrically spaced) and the routing of the wires underneath and into the loco's body is particularly challenging. Consider methodically how this is going to work and tackle one piece at a time starting at the lamp, then working your way along the wires until they are safely inside the body. You will want to consider fitting all 3 buffer-beam lamps first (to the point where they are glued in place, then fix down the wires together). Use a red vertical-mount (BLACK/BLUE + YELLOW wires) in the centre if the buffer-beam. You will mostly likely need to remove the existing lamp irons in order to place them properly. Drill holes directly down into the buffer beam once you have measured up their location, and fit the lamp in a similar manner to the other lamps that you've already done (super-glue from the underneath). Once this lamp is secure, move onto the other buffer-beam lamps - we'll worry about where the wires go afterwards.
  7. Fit buffer-beam yellow lamps x2 + resistors (F0 - forward motion)... similar to the red centre lamp, fit these 2 lamps either side of the buffer beam. Use yellow vertical-mount lamps (BLACK/BLUE + white wires).
  8. Route the buffer-beam lamp wires... You will not be able to take the wires directly down the centre of the body, as the chassis is attached there. Thus you will need to send wires down either side past where the cylinder block sit and up into the body that way. To make it balanced, split the centre lamp's wires one either side, so you end up with 3 wires down each side. You will need to drill small holes in the struts so that the centre wires can meet up with the outside lamp wires. Consider next how the wires will actually travel along the underside of the body and file off any sharp edge, or even file some recesses/ducts for the wires to sit in. Finally neatly arrange the 3 wires together and methodically use super-glue to 'pin' them down when you want them, and do the same on the other side with the other 3 wires. Once the glue is thoroughly dried, apply some black acrylic paint to the wires to hide them.
  9. Fit buffer-beam lamp resistors... Trim the wires for the buffer beam lamps appropriately and fit resistors to each of the 3 positive wires (BLUE/BLACK) and cover the resistors in heat-shrink tube. It is convenient to join the 3 resistors on the 'free' end with some wire so that the 6 wires from the lamps become 4. This way you can fix the bulk of the spare wire inside the boiler out of the way and only have 4 wires to route to the decoder. It also means that you can hide the resistors in the boiler too, which although small, do take some valuable space.
  10. Fit 4-pin connector for tender connection... The last component to install is the 4-pin connector that will send signals back to the tender. Drill a hole in the cab dead in the centre almost on the floor. Do this from the driver's side, NOT from within the loco's body, or you'll most likely 'mis-aim'! The hole needs to be big enough to feed the 4-wire lead of the 4-pin plug through. It will probably feel like it is way too big, but once the wires are inserted, the hole isn't too visible (it is all black, as are the wires themselves). Feed enough wire through so that the plug extends only around 1cm from the end of the foot-plate at the back of the cab. It has to be enough wire to reach the tender, and enough to comfortably insert the plug into the socket, but not so much that it curls up and gets in the way. Once you think you've got a good length, use some electrical tape to fix the wire inside the loco's body pointing the 4-wire bunch vertically up into the shell. You might also like to take the opportunity to fix these 4 wires and also the firebox and cab light wires to the inside roof of the shell. There is some space available right at the top (where the cab light wires come through) for some wiring and some resistors to fit.
  11. Add crew... This can be a convenient time to add your crew to the cab, or you can wait until everything is reassembled again. Try to find positions for your crew that do not interfere with the loco-to-tender wire, and that give some visibility to the firebox glow light, as well as ensuring that they are far enough inside the cab that they do not affect cornerning when the tender is attached. Use whatever glue you feel comfortable with (I use a dab of super-glue to initially fix them, then some thicker UHU glue which I leave overnight to set them properly in place). You'll probably want to touch up where the glue is afterwards with a little black paint.
  12. Test individual body components... a final test of each component is always a good idea at this stage, so do that using your DC power supply. It is also worth tidying up the positive wires and consolidating them neatly into a single wire ready for connection to the decoder's blue function 'common positive' lead. You'll have positive leads from each lamp, one for firebox light, one for cab light, one for smoke and one from the 4-pin connector too. You can then tuck the rest of the positive wires out of the way and secure them down with some electrical tape somewhere. You can also do the same for some of the other function wires, including connecting the 2 white wires from the front buffer-beam to the yellow of the 4-pin connector lead. Also, the single yellow wire from the front buffer-beam centre lamp and the white wire from the 4-pin connector lead. You've got to join these together anyway, so you might as well make it as neat as possible before you begin the 'cramming' process of putting the body back on the chassis.

Loco Reassembly

  1. Solder function wire to components... At this point you should ensure that you are totall happy with the components, and the neatness of the internal wiring, as once you start to solder the decoder's function wires they will be joined at the hip, as least to a certain extent! Here's a break-down of the wires and their colours as I would normally try to configure them, which includes 7 function outputs (we've left 1 spare function output on the decoder just in case you fancy doing something else with it in the future, or one of the others gets damaged somehow): decoder BLUE->positive for all functions; decoder WHITE->forward motion lamps (2 front yellow lamps and the red internal tender lamp); decoder YELLOW->reverse motion lamps (1 front red lamp and 1 tender yellow lamp); decoder GREEN->coach lighting (the 4-pin connector's green-ended wire); decoder PURPLE->smoke unit; decoder short PINK->firebox glow; decoder short GREY->cab light; decoder short PURPLE->boiler door lamp. Protect each connection with a little piece of heat-shrink.
  2. Test everything using DCC control... Before putting the body and chassis together again, so a proper DCC test by placing the chassis (and tender) all connected up on the track, and test that each function does actually respond correctly, including the directional lights doing what you expect them to do (it is easy to get the yellow and white mixed up).
  3. Tidy wiring where possible... The final thing to do before reassembly is to tape down as much of the loose wiring as you can. Much of it can be taped onto the motor using a long thin strip of electrical tape, although you may find it easiest to secure some of it to the inside roof of the body. You wont get it 100% tidied - it just isn't physically possible with permanent wiring. Maybe perform another full DCC test again to ensure you haven't upset anything.
  4. Reassemble body to chassis... The moment of truth comes... does it all fit? Well, it should, perhaps with a little tweaking of wires as it goes on. I find it is easiest to start with the chassis and body upside-down in my hand and fit the rear lugs into place under the cab, then turn it right-way-up and gently (but with a controlled firmness) ease the chassis into the body. Inevitably there will be one or two wires that need encouraging to go up inside, instead of dangling down the side of the chassis, but it shouldn't be too tricky. The front screw point should go back down flush into place with a little press (too much pressure and you'll probably need to adjust the position of some of the wiring up in the body. In fact, too much pressure will result in the shaped dome on the top of the body popping out. Once it all fits comfortably, put the large screw back into place under the front bogie. As you are putting the body back on, ensure that the speedo hangs freely, or it will get stuck up inside against the wheels, and there is a danger of it being snapped off entirely.
  5. Refit speedo... First try another full DCC test to ensure that you have all functions, motor and sound working correctly, and that the motion seems to be smooth. After this, use the 'spinner' to take out the bolt and refit the speedo arm back in the original position, together with any spacer that was there, ensuring that the speedo pivot is almost in the centre of the back driving wheel, and that the arm points in the same direction that it originally did.

Test / Play

  1. Place driver's cap on head
  2. Ensure loco and tender and connected and placed correctly onto track
  3. Have a friend blow a guard's whistle (or press F12!) and gently wave a green flag ensuring you do not poke the end of the flag near anyone's eyes
  4. Insert a few drops of smoke oil
  5. Take in the sounds, sights and smells of the Flying Scotsman in its full model glory!
  6. When family members call you for tea, do one more loop (maybe two) and go enjoy a beer.


Please note that these guides are provided as useful resources for you, as-is. YouChoos cannot be held responsible for errors in the information, or for any damage caused to your models or equipment if you choose to follow any of the steps detailed here.

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