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Nick Mitchell

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  1. Just a quick update on the wheels. In the end I decided to have a go with some home-made transfers to see how they would turn out. Nothing ventured, nothing gained... I used Fox transfer paper, and sprayed an area gloss green to match the wheels. Then I used a bow-pen compass to draw the red circles. Getting a nice result with such tiny circles proved very difficult indeed. In the end I drew over a hundred to get 8-10 I was reasonably happy with. There was no way I could draw a black line neatly inside the red line with the compasses (I did try), so I brushed the centres in as neatly as I could. I couldn't cut neat circles around the red lines, but the green background disguises any crudeness fairly effectively. In between each stage, there was a couple of days waiting time for the paint to harden. The photo below is very cruel - you can detect the edges of the transfers (which I hope will disappear under varnish), but I think I have managed to get them reasonably well centred. To the naked eye they look OK. While I had the airbrush out, I masked off the frames and sprayed the boiler bottom green. I experimented by adding some lime green into the dark green, and am pleased with how it has turned out. On some photos of the prototype, the wheels appear a slightly darker, less yellow, shade. It could be a trick of the light, or a feature different cleaning materials being used for the wheels and the upper-works. Maybe "colliery grot" would have been a more sensible choice of livery?
  2. Sometimes in model making you take one step forward and 2 steps back. Recently I took so many steps back so quickly that I nearly fell over. Somehow I managed to kill a decoder (I think there was a short between motor terminals when under power, but I'll never be certain). Yes, it was a precious CT decoder made from pure unobtanium (unless you are prepared to pay €20 to have one posted form Austria). In taking things to bits to extract the lifeless corpse of said decoder, I managed to stop the motor from working. The wheels have somehow ended up out of quarter too, but that is another story... all told, it was one of those days I wish I'd stayed in bed! The motor is the subject of this post, and is one of the Farish-like 7mm coreless ones which were available fleetingly for very low prices on eBay a few years ago. How I wish I'd bought more of them, with currently available equivalents being 10 times the price (though still only half the price of the decoder... grrr...). I soon worked out what the problem was - one of the wires had broken inside its plastic sleeving. Typically, the break was exactly at the point the wire emerges from the motor casing. Given what I'd paid for it, the obvious thing to do would be to bin the motor and replace it... but living so close to the Yorkshire border, I thought I'd pull it to bits and see if i could replace the broken wire. Here are a few pictures of what is on the inside of these motors in case anyone is curious. After prising off the end, this is the view down the case. The little bead on the end of the commutator rubs against the plastic end cap. Sliding out the coil reveals the fixed magnet that it spins around. You can also see the brass bearing that the shaft runs in. The coil itself is a thing of beauty: The plastic end cap contains the brushes, which are soldered to the terminal wires. Here I have cut off the broken red wire. The plastic sleeve is pretty well secured with glue (presumably some sort of epoxy?), but the wire inside it is very fragile. The Achilles Heel of the design, really. On the inside, the glue covers the soldered joint. In the photo below I have removed the brush for the red wire, carved away the glue, and drilled through the hole. What is left is the brush for the black wire unmolested... for now. As well as being held by the glue, you can see the brush is located in a slot in the plastic moulding. Obviously the brush is very delicate. Somehow I managed to extract it without mangling it. This was achieved by gently prising it upwards from underneath next to the plastic slot with a very small watchmakers screwdriver. I attempted to measure the thickness of the metal with my digital spanner and got 1 thou. Soldering wires onto decoder pads for stay-alive has been good training for soldering the replacement wire onto the brush spring. Since taking the picture below, I have trimmed the excess wire. The wire I used is decoder wire. I save all the bits that get cut off when I'm installing decoders for occasions such as this. I had trouble getting the brush to go back in its slot in the plastic, and was in danger of crushing it. In the end, I used a scalpel to open out the slot a bit, then after fitting the brush, touched it with a soldering iron to try and melt it secure. It looks a bit messy, but seems to have done the trick. I put a blob of epoxy over the end of the wire, and once it had set reassembled the motor. The trickiest part was getting the commutator between the brushes without bending them out of shape - and holding it there with the case was slid on. The orientation of the end cap is important, so that the brush contacts and the magnetic field are in alignment. The cap itself has markings, but the metal case does not. What I should have done is mark the case before I removed the end cap. Trial and error established the correct orientation and the motor once again ran sweetly... and intermittently. Of course, with all the handling, the black wire has now broken in exactly the same place. It was inevitable that it would, and far better now. I would have probably replaced it anyway, but the option of laziness has been removed. With the second one, the brush went back into its slot much more easily. I'm now waiting for the second lot of epoxy to harden before it all goes back together yet again. This time I did mark the outer case. The postman has just been, but nothing from Austria today - only bills. I wonder what the pioneers of 2mm modelling who had to knit their own motors from cobwebs would think of this?
  3. Courage suitably plucked, I've had a go at the edge lining on the frames, using a compass bow pen to off-set the lines. Below are some very cruel close-up views of the left and right sides. The red lines look a little thick, but viewed with the naked eye they're barely visible. I couldn't continue the line across the brake shaft bearing, and it looks a little wobbly where I've touched it in... but it will end up behind the cab steps. Off-setting along the bottom edge, there are also gaps where the spring hangers are. These gaps will be covered by the wheels, so I have left them alone. While I had the red paint out, I brush-painted the inside of the frames. While I had the black paint out, I painted the wheel rims. Here are three of them placed in the frames for effect. The lining on the frames looks very subtle in this context, and I'm pleased with it. The wheels should also have a red-lined black circle on the axle ends. I'm not sure how or whether I'll be able to tackle this. With the crank pins in place, using the compass won't take me all the way round the circle. Making some transfers would be one way, but aligning them centrally would be difficult. Having them off-centre would look worse than leaving them plain green. I've made only a little progress on the body. I managed to solder a false back into the smokebox to fill in the gaps mentioned in an earlier post. The buffers and the firebox sides have been fitted, and I've started drilling holes in the tank for the handrails etc.
  4. If you want a use for guitar strings in 2mm, try a shock absorbing wagon from the time before the springs were covered over in the mid '50s... This one has springs made from brass wound steel bottom E string. The vac pipe for comparison doesn't look like a spring(!)
  5. I usually use 0.45mm copper wire. I leave mine plain rather than winding wire round to represent the ribbing. If you have access to the 2mm Magazine archive, you really ought to read Pete Wright's article "The Skirl O'The Pipes" in the August 1992 issue. Below is a wagon with the first vacuum pipe I ever made - exactly according to Pete's "recipe". (Ignore the horribly applied transfers on the wagon sides - I was young and didn't know what I was doing)
  6. I Haven't made much progress with the Hunslet recently as I have been busy with other things (mostly work). While I had my airbrush out to paint the Coal Tank (as described here) I took the opportunity to prime and paint the frames. To get ready for this, all the soldering jobs on the frames have been completed - buffer beam brackets added, Simpson springs fitted, brake hangers fitted. I made a decision to leave off the sand boxes for now, as I thought they would interfere with lining the edge of the frames. As with the Coal Tank, I primed the frames with etching primer, then cast about for a suitable paint for the top coat. A purplish brown is called for. I had an old tin of Humbrol paint No 107 which isn't in the current listings. From what was spilled round the top of the tin, it looked about the right colour and gloss. When I sprayed it, however, it was much paler and matt. I intend to make an attempt at lining the frames, so really wanted a gloss surface. In the end, I mixed up a shade which I think looks about right from gloss paints I had. I used 6 drops of Tan, 6 drops of Red, 2 drops of black and 1 drop of blue. These were mixed together with approximately the same amount of white spirit for spraying. I masked the bearings inside and out with small blobs of Blu-Tak, and used Tamiya tape to cover the Simpson springs. I didn't worry about getting overspray on the underside of the boiler, or on the inside of the frames. The inside of the frames and the balance weight will be brush painted bright red eventually. This is where I'm up to: I'm now plucking up the courage to attack the lining before I can fit the wheels... There will be a black edge with a thin red line.
  7. My airbrush has been out, and I've given my coal tank a coat of Precision 2-pack etching primer (using Ian Rathbone's recipe of 1part paint, 2 parts activated thinners and 1 part cellulose thinners). This was followed by gloss black enamel (Humbrol 21) thinned 50:50 with white spirit. The spraying process felt less stressful this time, following a weekend pre-lockdown with Ian at Missenden, and I was more in control of things. For the gloss, I was using lower air pressure, less paint, and moving more slowly. The results are below. The surface is not as smooth as Mr Rathbone himself would achieve, but I'm pleased with it. The roof is loosely placed in position in these pictures, hence the daylight showing. The stress returned with the application of the transfers. Well, actually, it was not so much the application, but what came next... I'm using un-shaded straw coloured transfers, as that's what most Coal Tanks seemed to display round about the time I am interested in. The Fox transfer sheet has 14" letters and 10" or 12" numerals. This restricted me to a 5-digit numbered engine (as some of them became when a particular number series needed to be vacated in the 1930s) because they mainly received 12" numerals, whereas the locos retaining 4 digit numbers tended to have 14" numerals. I wanted to portray an engine without push-pull gear, that would have seen around north Manchester around the time of nationalisation. 27619 (originally 273, then 7619) fitted the bill, calling Plodder Lane home as 1948 dawned. It was to have become 58890 under BR, but did not last long enough to receive its BR number or livery, being withdrawn from Speke at the end of '49. The Fireman's side turned out OK: The 6 looks to be leaning back, but sometimes they did on the real thing. When it came to the Driver's side, some bits of the transfers started flaking away. Part of the serif at the bottom right of the M went, and some chunks of the 7 disappeared too. I can only think that perhaps the paint and the varnish were not in perfect registration on the transfer sheet. The 7 was bad, so I replaced it with another one. This also had some bits that disappeared, although they were not as large. In the end I decided I couldn't live with the 7 the way it was, so decided to make a 3rd attempt. I had left the decision too long, as it had already stuck, and when I removed it the paint underneath came away too: Unfortunately, my tale of disaster didn't stop there. In the above picture, you may be able to notice that the cab rear handrail has come adrift at the top end. I don't know how many times it got soldered back on during construction, but superglue is the only option now. I fully expect it to be a regular source of frustration! Also, I had attempted to brush a thin wash of cream on the inside of the cab. Capillary action had drawn the thinned paint through some cracks in the cab front sheet and out onto the front of the engine. I applied this cream paint the top half of the cab rear as well. Photographs show plenty of LMS liveried coal tanks with what looks like plain black cab rears, but a few are definitely a lighter shade. I figured that since I had put so much effort into the cab interior, having it paler would help reflect a bit of light in there and make the interior slightly less invisible. Obviously, the gloss black helped this to creep into more unwanted places, like down the edge of the cab rear and along the bottom of the tank trunks. I thought I could remove this stray paint by soaking it up into a brush dampened with white spirit. That worked, but alas a bit too efficiently, and I managed to remove some of the black paint from a couple of places along with the cream. Some of the black paint had rubbed off the footplate edge under the cab too (also visible in the above picture) and I decided I needed to re-spray a few places. Not wanting to go through the experience of aligning and replacing transfers again, I decided to try and mask off those already in place and spray only the bits that needed re-covering. The photo below should illustrate where I was aiming for, with the bunker being an extreme case of optimism that I wouldn't end up with ridges against the masking and the edges of the existing paint. Well, I did end up with some ridges. I thought I might soften them a little with white spirit blown on with the airbrush... (will he never learn?) but didn't have much success other than at creating extra ripples. It was now 50:50 whether I was going to need to rub down the entire bunker panel and start again. I had a go at very gently rubbing the edges of the ridges and ripples with 1500 grit paper, and applied a new transfer 7 to see how bad it looks. In the picture below, I had recently applied decal setting solution (Micro Sol) which is why the surface round the 7 looks a bit crinkly. This will shrink down flat in a little while to match the others. Have I got away with it? I think that once this panel is varnished an d weathered, it will probably look OK. To end on a more positive note, I bought some Citadel "dry" paint by mistake last year. I wanted some gold paint, and didn't understand what I was buying. When I opened it, it was more like golden jelly than paint, and I thought it had gone off. A few minutes later and YouTube had set me straight about this paint which is specially made ready to dry brush. It is intended for highlighting the details of goblin armour and the like, but I though I'd give it a go in the cab of my coal tank. I'm quite pleased with how it has picked out the controls. Maybe I should have a couple of goblins in there shovelling coal... Now I need to paint the chassis, and then weather the two halves as one complete unit.
  8. Thanks for the clarification. It is a while since I bought the etch, so I guess the part must have got separated and found its way into a different hiding place. One sure-fire way of finding a missing piece is to make a replacement. I fully expect to discover a mysterious rectangle of Nickel Silver in a strange place some time during the next few days... at least I'll know what it is when I find it now!
  9. Only a small amount of progress to report in the last couple of weeks due to a huge pile of exam marking, but things are heading in the right direction. The kit provides some very nice strengthening brackets which fit to the frames behind the buffer beams. They're half-etched, with rivet detail. I intend to solder these to the frames only, but there are a few things that need to happen first. To maintain electrical isolation between the frames and body, I will have to fit a layer of insulating material to the buffer beams. The frames themselves will need to be shortened slightly to accommodate this. Also, the buffers will have to be soldered to the beams and filed flush at the rear before the insulation can be fitted. Only then can I solder the brackets to the frames so they fit tight up against the buffer beams and don't look silly. So, to the buffers. I found some in my collection which had square bases, were the right length, and had appropriate diameter housings. Alas, I have no idea as to their provenance. I modified them in my lathe to remove the lip from the end of the housings, and also to reduce the diameter of the heads. Here is the "after" photo - I didn't think to take a "before. The spigots are 1.0mm diameter, but unfortunately the holes in the etched buffer beams are 1.2mm. I will need to turn some collars before I can fit them. In other news, the saddle tank has been delivered ready for fitting: When Mike said that I had all the etched parts from the 4mm kit, I'm not sure if that means the 4mm kit doesn't have a wrapper for the tank, or I had one and lost it? Nevertheless, I am without what the instructions refer to a part 18, and needed to make my own. Taking note from Jim Watt, this was made from 5 thou. brass sheet. I had wondered about using some tube for this, but thought I'd try the rolled sheet method first as an experiment. Either I had beginner's luck, or it isn't as hard as I was worried it might be... I'm pleased with the result at any rate, and won't be needing to order some tube. By measuring the etched tank formers, I was able to calculate the size of the brass rectangle. I rolled the centre section first, but mostly this became un-rolled again when forming the tight bends at the bottom of the tank. Still, having something of a curve there helped restore the correct profile afterwards. The tight curves were formed round lengths of 1.5mm axle steel held in the vice as shown below. I marked the extent of the flat section at the edge of the tank first, so the bend would start in the right place, and I could see that it was parallel to the edge of the tank. I didn't need to anneal the brass to do this. It was then a case of soldering in the front and rear ends, using spring clips to hold the wrapper tightly around them. The rear end (seen below) features 3 lugs to locate the tank onto the cab front. The front end has an additional overlay with rivet detail. In the following pictures, the tank is just resting in place against the smokebox. It is quite flexible at this stage, and I will need to do some tweaking and adjustments before soldering it in place. The tank will give the footplate rigidity, but I need to make sure it is straight and rigid, not bent and rigid! One part of me says I should paint and line the tank before fixing it, but another part (which will certainly win the argument) says solder everything up solid first for strength.
  10. Funnily enough, I had been thinking about this recently, inspired by John Birkett-Smith's article in the October 1985 Magazine. Lots of L&Y locos had Joy valve gear, and in some instances bits of it projected above the level of the footplate. This isn't my video, but you can clearly see ends of the rods which connect to the valve spindles bobbing up and down between the top of frames and the bottom of the boiler.
  11. Makes a refreshing change from the sorts of things I usually get blamed for!
  12. If some natural disaster were to wipe away my modelling bench, my minimal shopping list for tools to get back to soldering basic Association wagon kits would be: Antex 25 watt iron, with 1mm bit. Soldering iron stand. Brass wool tip cleaner. 60/40 tin lead electrical solder. Powerflow paste flux. Swann Morton scalpel with No. 10 blades. #4 cut Swiss file, pillar. Stainless steel tweezers (MM). Set of 6 small cutting broaches. Small engineers square and 6" steel ruler. Fine Garryflex block. Wooden cocktail sticks. Piece of hardboard, and maybe a couple of bits of planed softwood to attach to it. Positionable lamp. The above is entirely my personal preference. I'm sure plenty would cringe at my choice of solder and flux especially... but it works for me.
  13. I don't wish to challenge Mr. Townsley's authority on all things Hunslet, but all the photos I can find have the balance weight anti-clockwise from the crank pin as you look side-on at the loco. There were some differences between the first-built 16" loco and the ones that followed, but I don't believe they extended to the balancing. I must be misinterpreting the drawing. As far as I know, all the 16" locos were built by Hunslet themselves. The Austerities were much bigger and had 18" cylinders (although not all 18" Hunslets were Austerities). To illustrate the difference between these two classes of engine, below is a photo I took from the footplate(s!) a few years ago at Bolton Abbey. The Austerity (on the left, masquerading as a J94 to confuse things even more) is one of those not built by Hunslet (Robert Stephenson in 1943 iirc).
  14. It has been almost a week since my last post, and on the surface not a lot looks to have happened. I've been obsessing over lots of very small fiddly details that will probably not be too noticeable once the model is complete. Having spent so many hours up close and personal with the real thing, rag in hand, I want to go to town with the detail. Normally, I would paint the frames behind where the wheels will be, get the chassis working mechanically, and then add further details. With this loco, I have decided to try a different approach and put as much detail on the chassis as I can, and paint it fully before fitting the wheels. Partly this is because there is quite a bit of detail in the kit to put on, and partly because the chassis is going to be painted on a nice shade of dark red rather than the usual "grot" colour. This is where I'm up to with the chassis: After adding a front support for the boiler (soldered to the boiler first, and then to the front spacer whilst the boiler was packed to the correct height), additional details have been added between the frames. The ability to attempt this sort of silliness is one of the things I like about this method of chassis construction. Working forward from the rear, these start with the frame stretcher in front of the firebox front. This was made from a re-shaped frame spacer. I took two attempts at fitting this. The first time had the folded "leg" of the spacer pointing down, but I wasn't happy with it so re-fitted it this way round. Next came the reversing gear counter-weight and weigh shaft. The weight is made from a lump of PCB sandwiched between two layers of nickel silver, with the weigh shaft in two halves, located in holes drilled in the nickel silver but not through the PCB. There were holes etched in the frames in line with where the weight shaft should be. I don't know if they were intended for the weigh shaft, or were part of the compensation arrangements. Either way, they were about a millimetre two low down on the frames for my purposes. I drilled them out to 0.5mm, soldered in a short piece of brass rod, then filed this flush with the frames to "delete" them. New holes nearer the top edge of the frames were then marked and drilled to take the weigh shaft. On the first attempt, in my excitement I managed to fit the counter-weight backwards! On the right side, the bottom end of the crank that attaches to the reach rod has been added and filed flush with the top edge of the frame. Functionally an additional frame spacer, there is a suggestion of the motion plate, with the top slide bars and valve spindles attached. The slide bars are chopped up spare bits of the fret, and the valve spindles and trunk guides represented by 0.45mm rod and 0.8mm tube. The slidebars and spindles were lined up and stuck to a piece of paper with Pritt, then the top half of the motion plate (another re-shaped frame spacer) held down and soldered at right angles. Another bit of frame spacer was soldered at the front end. Here's a view from underneath, showing more clearly the details between the frames: With these additional spacers soldered to the previously installed PCB pads, I could solder the footplate support brackets into the the slots outside of the frames without fear of pushing the PCB pads out of place. The brackets as supplied had to be chopped up to make 4 separate brackets. Side pieces - little strips with rivet heads on - were added separately afterwards - some of the tiniest etched parts I have come across. Also added on the outside of the frames are the little triangular plates where the brake hangers will poke through. These were provided in the kit, as were the guard irons. The triangular plates were lined up for soldering with a broken 0.3mm drill. I have plenty of these... On the body front, I have attacked the smokebox. There are 3 wrappers on the etch. I have just used the first half-etched wrapper. The instructions say the other two are to "thicken" the smokebox. I don't know whether that means they should go inside or outside the wrapper I have fitted. As it stands, the smokebox is the correct size and quite robust, so I shan't ruin things attempting to install the additional wrappers. As with the cab, I disobeyed the instructions and attached the smokebox "floor" to the footplate first. I aligned it with lengths of 0.5mm rod, which were subsequently removed. I had to add the wrapper to the smokebox front separately, then file the bottom edges of the wrapper flush so that the smokebox could be fitted to the footplate around it's floor and soldered from the inside. Finally, the rear wall of the smokebox was soldered in place using the hole in the smokebox front for access. Because I have used a tube for the boiler bottom which is too narrow (so it fits through the footplate) there is a gap left which will be visible under the tank, and needs to be filled. It is quite noticeable in the picture below... I'm not sure how I will tackle this yet. One lesson learned is to not trust drawings. I worked out (eventually, after things didn't quite add up) that the 4mm drawing in Railway Modeller is about 10% over scale. It also has some errors, including the positioning of the balance weights on the driven axle. Obviously I only realised this after I'd glued them in the wrong place and painted them! These have now been corrected. The photo below shows one set of wheels just placed in the bearings for effect. That re-positioned centre balance weight is thicker than the other two (1.5 layers of etch) and stands out further than the wheel tyres. I think the difference is noticeable and worthwhile. It means that I will have to space the coupling rods further off the wheels. I've still got a few bits to add before I can paint the frames - Simpson springs, buffer beam brackets and brake hanger rods. Possibly also the rear brake cross rod. These latter will be cut through at a later stage. I'm itching to get to the point where I can get the gears and wheels in and test the chassis...
  15. Having established the height of the worm, I was able to measure and mark the opening necessary in the front of the cab. It has to clear the frame extensions as well as the worm itself. Once the opening was filed to shape and checked for fit, I could assemble the cab around the base already fitted to the footplate. I started by adding the front sheet, using the end of a steel rule to make sure it was central and vertical, then added the left side sheet. The sides overlap the central section, so I could push the side up against a piece of wood held across the cab front to get it in the right place. The bottom part of the cab rear was added next, then the bunker back. To get the bunker back to fit nicely, I filed a chamfer along the inside of the bottom edge, so that it fitted vertically against the back of the cab floor. The cab right side sheet came next, then the top part of the cab rear. Some work with fine files can then disguise the butt joints. The cab sides have a support piece across the doorway. This is a really neat touch to avoid the cab side distorting during assembly. Later on it will need to be cut away. With the cab in place, I could open out the hole under the bunker to enable the tantalum chip capacitors to fit through it. Front to back, the hole is the maximum possible dimension, and there isn't a lot of wriggle room. Two 220uF capacitors will fit comfortably as can be seen below. I could possibly make the slot wider and fit 3 capacitors, but I would rather not weaken things too much. Also, with just 2 capacitors, the other components of the stay alive circuit can fit at the side of them. If 440uF proves to be insufficient, I can always revisit this decision later. The capacitors will need to lean backwards to avoid the ledge in the back of the cab. They don't come up to the very top of the bunker, so a false top and a convincingly shaped coal load ought to be possible. On the chassis front, I have been playing with wheels. Having cleaned the burrs/flash from between the spokes, when I came to solder in the crank pins from behind I noticed that several of the wheels didn't have much of a boss on the back. One of them didn't seem to have a boss at all. Most had the thickness of the spokes reduced at the rear, but only at the very outside edge. There were 2 problems with this: 1. Having filed the frame bushes flush to the frames, there was a danger of the back of the spokes rubbing against the frames; 2. Soldering the crank pin to the rear of the wheel could leave a protrusion to bind against the frame. The second problem could be mitigated to an extent by countersinking the hole where the crank pin will be soldered (which I do anyway), but the first problem was more serious. Anyway, I soldered in the crankpins, but on the wheel with no boss at all, the solder wicked round the axle and left a blob where the boss would have been. To remedy this, I had to put the wheel in the lathe to turn off the solder (filing it wouldn't have left as smooth a bearing surface). While it was there, I turned the back of the spokes down to be level with the back of the tyre, leaving a nice boss. This made such a difference that I did the same for all the wheels. Of course I now had to go over them all again removing all the new burrs I'd raised on the spokes! Hopefully the new Association Mk. V wheels won't need any of this sort of remedial work. (I have plenty of Mk IV wheels in my gloat box for not-yet-started kits, however...) With the balance weights glued on position, the wheels now have their first coat of paint. I have been agonising over how to turn out the locomotive. Should it be in scruffy NCB condition? Or should I try to represent the Beatrice I know and love in active retirement, all shiny and beautiful? My wife's opinion is that since I went on Ian Rathbone's lining course at Missenden, I jolly well ought to do the fully lined "as preserved" livery. Whether I can manage it remains to be seen - there is edge lining and panel lining - even the sand-boxes on the frames are edge-lined! I might end up with a simplified version. So... green it is, but what shade of green? It is quite dark, but lighter than GWR/BR brunswick green. I considered Humbrol 80 Grass Green. I had a (very) old tin that I had been given, and also a much newer unopened tin. Out of curiosity I opened the old tin, and to my surprise the paint was absolutely fine... but the two greens seem to be completely different colours. The photo doesn't show the actual colour, but does highlight the difference: In the end, I opted for a different green anyway - Humbrol 3 Emerald green. If I'm going to attempt all that lining, I really want a gloss base. The wheels will need another coat of green, and the tyres need painting black. I've got a bit of detailing work to do to the frames before I can paint behind where the wheels will be and wheel up the chassis.
  16. My "lockdown loco" is progressing well - if slowly. I have been taking my time in tackling the difficult bit of attaching the boiler in the right place. First task was to make the boiler. With saw cuts and filing, a length of 8mm tube approx. 22mm long was hacked in half, and the firebox spacer attached to the underside. The position of the spacer was measured from what will be the front end of the tube. I decided to leave a section of the boiler near the firebox end as a complete ring, to hold the motor. If it doesn't work out I can always remove it later. The height of the spacer was a bit of a guesstimate. I had a window of about 1mm height adjustment if the horizontal section was to land on the PCB pad on the frames. I soldered the spacer to the boiler from the firebox side before bending over the horizontal part. The bend was then reinforced with more solder. Outside sheds on preserved railways up and down the country you see upturned boilers under restoration just like this... well, sort of! The height of the boiler needs to be set by the mesh of the worm, so the gears need mounting on muffs and the worm attaching to the motor to get everything set up. I forgot to order a worm shaft adaptor from Shop 3 when I ordered the wheels, so I made a 6mm long one on my lathe from axle steel. Taking a leaf from Anthony's book (well, blog) I epoxied the worm/adaptor to the motor shaft and left the motor running while the glue was setting. The motor stuck itself to the steel case of the controller, and after dangling nose-down, a perfectly concentric worm mounting was the result. While I had the axle steel in the lathe, I turned a pair of 3mm stub axles for the intermediate gear shaft. One end of each was chamfered to ease fitting into the muff. These won't be used until the gear is finally fitted. For now, I'll be using a 1.4mm drill shank for temporarily fitting the gears. The mesh of the spur gears was very tight - in fact they were jammed together. I obviously hadn't drilled the additional hole in the frame extensions accurately enough. Substituting the 21 tooth spur gear with a 20 tooth gear (fortunately I had one in my spares box) has resulted in another fine mesh. To set the mesh of the worm, I experimented with various shims between the frame tops and the boiler, with the motor resting in place. Best results were achieved with a 0.75mm gap. This should leave 0.5mm between the top of the footplate and the bottom of the boiler, which is perfect. I won't need to worry about adding any kind of wrapper to the boiler bottom. The boiler was clamped in place with an aluminium curl clip, while the spacer was soldered to the frames from underneath. The prongs of the clip were bent to be roughly parallel, and more shim used to adjust the rotation of the boiler tube so that the bottom of the spacer was level. The front of the boiler tube is aligned with the rear of the front spacer (which itself was lined up with the gap in the footplate where the rear of the smokebox will be). Here are a couple of shots after soldering and with the footplate slotted over the top, to see how things are coming along. The firebox spacer is actually holding the tube quite rigidly, but as some stage I plan to solder a support at the very front of the boiler, connecting it to the front spacer. The footplate and boiler need to remain parallel, or as well as looking wrong, the worm will come out of mesh. I re-fitted the gears and motor to check the mesh was still OK before moving on. Here's an action shot to prove everything is running nicely. For now...
  17. Tin the PCB. Tin an area of the frame slightly larger than the PCB. Tinning needs to be done sparingly so that you don't have big lumps of solder. Add a little more flux and position the PCB - holding it in place with a cocktail stick or similar. With a little more solder on the iron, heat the tinned area adjacent to the PCB on the same side of the frame. You will see the flux bubble out and the solder flash round. If it is a big pad, you might need to introduce the iron in a few different places. With the Hunslet, I had filed the bearings flush on the outside of the frame, so there was no danger of them being disturbed by soldering on the PCB. In other situations, you may need to be careful not inadvertently press a bearing out of the frame. You can watch me doing this in Part 8 of my Jubilee insomnia cure videos.
  18. I could have filed down the "wide" spacers that came as part of the kit, but it is easier to use some of the ones on the Nigel Hunt etch that are 6.5mm in width. Most of the holes are etched just under clearance diameter for 12BA. I am going to use the two spacers to the left with the rows of small holes, opening out the ones required to 14BA clarance. Below you can see the PCB insulating pads fixed to the frames. There will be a sizeable L shaped spacer at the front and the back. To the left if the gear tower, another L spacer will fold upwards to support the motor. The pad for this boiler support spacer covers a slot in the frame. The small square pad covers another slot. In a non-split frame chassis, the footplate support brackets stretch the whole way across the loco. Eventually, I will chop these up and solder just the outer ends into the slots in the frames. Between the small pads, I may well insert a representation of the motion plate and the tops of the slide bars. Also, the counterweight attached to the weighshaft for the reversing gear is quite prominent between the frames... but that is getting too far ahead of things! To position the front and rear spacers, I used the footplate as a jig. The spacers were bolted to the footplate (with a 14BA washer in between, to lower them slightly from the top edge of the frames). One of the frames, which are currently a snug fit between the buffer beams, can then be positioned against the spacers for soldering as below: Once the two spacers were fitted to the first frame, the second frame was added using the Association assembly jigs held parallel in my vice as normal. This is as far as I have got at the moment. I think I will add the cab front (at least) to the frames next, and butt up to that the cosmetic firebox sides. With the chassis bolted to the frames once again, I will be able to line up the boiler support spacer so it looks like the front of the firebox, and mark off its position. I will probably solder the spacer in place with the boiler already attached to it, so I can pack the gap between the bottom of the boiler and the top of the frames with shim to get the height correct.
  19. A little bit more progress to report. Working out the order in which to do things can be quite tricky when going "off piste" with a shrunken model like this. In order to make the boiler part of the chassis, I need parts of the "upper body" to line it up with. To make the upper body fit round the chassis, I need parts of the chassis. So, to put off making up my mind, I thought I'd solder the brake shoes to the brake hangers while the latter were held in place on the etch. That went well, until I tried drilling the holes at the top and bottom of the brake hangers. In the reduced size version of the kit, there just isn't enough metal around the hole. Even a 0.25mm drill broke through: Casting around for an alternative, I espied my first ever attempt at a 2mm loco made at least 15 years ago - a Poole-era Farish Jinty conversion using the Association kit of the time. It featured PCB frames screwed onto the (much hacked about) Farish chassis block. What is it about Jinties? Since that conversion kit there has been the Bob Jones chassis (of which I have two), the Chris Higgs chassis, and now the all new Association conversion components which I also bought... though given the quality of the latest Bachmann body, this one looks most likely to ever be finished now. Yet with all of these, you still end up with an over-scale model. I wish one of the many obviously Jinty-mad people would come up with a proper etched kit to 1:152 scale! Anyway, it turns out that the spacing between the top and bottom holes on those particular Jinty brake hangers is a dead match for the Hunslet, so the poor creature (which I never did manage to get running the way I wanted) was dispatched to the scrap yard for dismantling and parts recovery. A nice set of 9mm driving wheels, a DCX74zD decoder and a 30:1 worm gear set will hopefully have a more useful second life... Unsoldering the brake shoes I'd just soldered on to the too-narrow hangers inevitably resulted in one pinging off into oblivion. I heard it rattle against the wall at the back of my bench, so knew it wasn't in the carpet. Several hours later I found the thing hiding in a tray of bits for another half-built loco. One side-benefit is that I now have a very clean and tidy work bench! The Jinty brakes needed the paint scraping off, and their own fold-over brake shoes (which weren't the right shape) unsoldering and snapping off before the Hunslet shoes could replace them. I toyed with the idea of keeping the fold-round top parts of the brake hangers, which spaced them off the frames, but this would obliterate the tiny triangular frame overlay pieces included in the kit. When one of the Jinty spacers disintegrated whilst dismantling it, the decision was made for me. Here's the "new" hanger with the shoe from the Hunslet kit soldered in place, alongside the hanger it will replace: Procrastination complete, it was time to attack the footplate. The rectangular aperture in the middle was extended backwards just over 2mm to clear the end of the gear tower, then the buffer beams and valances were soldered on. The front buffer beam was fixed first, then the side valances. There is a half-etched lip round the edge of the footplate, which they butt up against. The valances are only 0.4mm deep, and consequently very delicate. They had quite a bit of cusp at one end which needed careful filing away. Fortunately my watchmakers vice is able to grip along the very edge of such tiny strips. I only smoothed one edge in the vice, soldered them in place, then smoothed off the other edge in situ. I could then file the rear end of them back flush with the half-etched rear overhang, and finally solder the rear buffer beam in position. If building a 4mm version of the kit, the cab is assembled round a 2-layer floor, which is then bolted to the footplate. (Same for the smokebox). I didn't think that would work in 2mm, so I soldered the cab floor directly to the footplate. There were some modifications to do beforehand, however. Firstly, a notch was filed out of the front edge of both layers to match the enlarged hole in the footplate. As designed, the chassis screws to the body with a captive nut inside the bunker. I want to use this area to house a Stay Alive, so I had to move the fixing point into the centre of the cab floor. This involved drilling a 14BA clearance hole in the footplate, and then a hole wide enough to bury a 14BA nut in the cab floor layers. The nut was soldered to the top of the footplate using my usual cocktail stick trick, with the stub of the cocktail stick left in place for subsequent operations. The original fixing holes in the bunker were all opened out to form the beginnings of a slot for the capacitors to poke up through. Taking a tip from Stephen Harris' wagon kits, I opened out the four would-be bolt holes in the corners of the cab floor to 1mm, and lined up the layers using top-hat bearings. These were soldered to the underside of the footplate first, then the cab floor layers sweated on one at a time. This is the underside of the cab, showing the alignment bearings. The flange of the bearings is slightly deeper than the valances! Here's the view from on top. I've filed the tops of the bearings and the nut flush with the floor. The slot at the rear will need making a bit wider to fit the capacitors through, but that will have to wait until the bunker is in place. I'll have to think of a different strategy, as the holes for lining up the smokebox base are in line with the frames. The plethora of rivets in the front buffer beam don't show up in the photo below, but the coupling hook surround is really nice. The driving wheels have just arrived from Shop 3, so construction will soon be on a roll... I had a moment of panic as I thought the wheel flanges might scrape against the bottom of the footplate, but there is clearance - just!
  20. Seriously over-rated, this discipline malarkey. I too have an un-touched Nigel Hunt 483 kit in stock... when we've finished starting our 16" Hunslets, we should have a 483 class build-off (at least up to the unpainted stage!)
  21. I've made a practical start by extending the frames. Not wanting to let bits go to waste, I used a couple of the "OO" spacers, which were roughly the right sort of size, and attached then to the frames above the rear axle hole, using scraps of the etch frame as reinforcing pieces at either side. This was done after the rear bearing had been soldered in and filed flush to the frame on the outside face, so I could line things up approximately. According to my plan, the axle with the worm wheel / 18T spur ear will be directly above the rear axle. Fortunately, when opening out the axle holes to 2.5mm to accept frame bushes (they were etched approx. 1.8mm), there was just enough metal surrounding the hole. Out of interest, the 2 tiny etched holes near the bottom edge of the frames are for locating pivots if you are installing compensating beams. I will use them as the fixing points for Simpson springs. Having used the Association gear meshing/marking tool with 1/8" points to gauge the spacing for the 18 and 21 tooth spur gears, I swapped one of the points to a 1.5mm one in the tool. This allowed me to use the rear axle bearing as a pivot, and scribe an arc at the correct meshing centre of the other axle onto the frame extension. Lining up the top edge of the frame against a horizontal line on my cutting mat, and sighting a vertical line through the centre of the bearing, I could line up a ruler against the same vertical line and scribe vertically to mark the centre of the new hole. The photo below shows the centre popped through the resulting cross-hair from the other side: I then used my Association frame assembly jig to clamp the two frames together (flush outside faces touching), and held the assembly in my vice to drill through both frames at once. In the photo below I am about to start drilling, with a sacrificial bit of coffee stirrer on the vice jaw to drill into. The hole was drilled undersize, then carefully opened out with a broach, one frame at a time. Holding it in my vice as shown below, I could clamp both parts of the frame to discourage them from pulling apart. Gently did it! Somehow I managed to solder in the bearings without everything falling apart, and after filing them back flush to the outside of the frames, you can hardly see the join. I will need to remove a section of the cab floor to accommodate this new gear tower, but it will only intrude a couple of mm into dark recesses at the front the cab. This last shot is rather cruel, and represents a very un-scientific attempt to see if the new holes were in the same place on both frames, buy threading through several lengths of axle steel and lining it up over the squares on my mat. The wonky photo doesn't make it clear, and I suppose I won't know for sure until I have erected the frames, but I think I am in the right ball-park.
  22. Would the idea be to use the prints as masters for brass casting? Nick Tilston has done this for some of the recent N Brass range, and the results are very nice. The very edge of the flare on his L&Y chimney for example (which is nice and wide and easy to measure) is 0.25mm thick. It has a 1mm printed spigot before attachment to the sprue.
  23. Thanks Jim. I enjoyed following your build at the time, and have just finished re-reading the thread. Lots of good stuff in there. I imagine it will be a while until I need to worry about the saddle tank though.
  24. You could say I'm digging a hole for myself here, couldn't you Simon? I'll get my coat...
  25. Don't think of the price of wheels in absolute terms. Compare it to the hours of effort you're going to put into this loco, and the frustration you'll feel every time you see it wobbling along. You're making such a nice job of things that an extra few pounds spent on getting it right at this stage will more than repay itself in the long term. I have learned that to ignore problems like this and carry on regardless is to create more work and frustration in the long run. My usual solution is to put the offending model to one side and work on something else while I come to terms with the bitter pill I know deep down i need to swallow.
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