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antyeates1983

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  1. I think the time spent fiddling with the chassis trying to get it to work with original motor definitely helped!
  2. It turns out that the cheap Chinese motors I bought on eBay are just that: cheap. Despite much fiddling with the motor position I couldn't get the original motor to turn the wheels while on the track. The chassis rolled freely with all of the gears and rods attached, but the motor would only turn the wheels if I held the chassis in mid-air, and then only if I held the motor in exactly the right place. On the track, it just wouldn't budge. Eventually I came to the conclusion that the motor just didn't have enough torque, and bought one of the Tramfabriek 0716 motors which are (newly) available from the 2mm Scale Association shop. The difference was magical! Here you see the new motor test fitted. The worm is now brass, because I couldn't get the old plastic one off the motor shaft. The eagle-eyed will spot that I replaced the worm bearing bracket with a heftier version, filed up from a block of solid brass rather than a bit of thin brass angle. This was part of my messing around with the eBay motor - I thought it was too loose and that might be preventing the worm from meshing correctly. Again, it has a phosphor bronze frame bush soldered in to take the little length of stub axle, which is a press fit into the worm. The worm sits on a 1mm shaft adaptor like before (I think it came from Nigel Lawton). This motor has a double-ended shaft, as you can see. Unfortunately I can't take advantage of this and fit a flywheel as there isn't room. Here is the motor after cutting off the unused shaft. This was done with a slitting disc in the minidrill. I had to cut it off quite close to the end of the motor because there is very little clearance lengthwise in the bunker. Even so, I had to file a bit off the motor support collar to get the body on. I found it useful to attach the wires to the motor with Kapton tape. At long last, the chassis has made its first successful test run - here's a video. For this I temporarily soldered the motor wires to the side frames, and balanced some lumps of lead on top to give it some hope of current collection. It's a bit more hesitant in the backward direction, but I will worry about this once I've dismantled the chassis for painting and put it back together again!
  3. To be honest, I'm not experienced with the lathe yet, so it is a bit of a case of trial and error!
  4. I made a start on the boiler "furniture" by making the dome. The first problem I faced was not having an accurate drawing of the real thing. This led to me making a first attempt, looking at it sat on the model, and then doing another one with slightly altered dimensions. Although it took some extra time, this did also mean that I had a practice run to work out my method. I started with some 8mm brass rod (annoyingly, the widest part of the flange was estimated to be a little more than 6mm, which was the next size down that I had. I started by chucking this in the lathe drilling a 1.5mm hole through the bottom, finishing somewhere midway up. I then reduced most of the extraneous material. For this I used a small semi-circular (home-ground) turning tool - this leaves the bell shape at the bottom. I then turned down the thin spigot at the top, which will eventually be reduced in size to make the small "blob" visible on the top of the real domes. I parted it off with a bit of extra full-diameter (8mm) rod, which you see here in black. Then I put it in a vice and carefully filed the base to "boiler shape" by hand. I find it useful to start with a triangular file (or even a saw blade) and widen this to get a straight line that is well centred. Then I start with a round needle file, followed by a larger round file, followed finally by some wet and dry wrapped around a spare length of the boiler tube. In this photo you can see the mounting hole in the bottom. Next stage is to make a temporary mandrel to hold the dome for remaining shaping in the lathe. This was turned down from a length of 6mm brass rod. I make it long enough that I can saw it off when done and let it double as the locating pin for attaching to the boiler. I left this in the chuck (to maintain concentricity) and attached the dome with cyano. I found that a reasonable amount was necessary to hold it on, but I didn't fancy trying to solder this large a lump of metal in the lathe. Next you see the use for the spigot at the top: it runs inside a length of brass tube held in the tailstock chuck, to support the piece during subsequent turning. I then turned the main diameter down to the correct (guessed) size. If this looks different to the previous photo, it's because this one is the initial test version, I think. The rounded end was then turned by hand with a graver. Here you see a length of tool steel held in the toolpost acting as a rest for the graver. Probably I should make a better one by turning one of these down to circular, but I haven't got around to it. The final job on the lathe was to turn down the "pip" at the top as much as I dared, using my usual parting tool. After taking it out of the chuck, I left it on the rod to allow me to hold it during final shaping of the bottom flange. I think there's no option here other than doing it carefully by hand with needle files and wet and dry. I then cut it off leaving enough of the spigot to mount it in the hole on the boiler:
  5. Next step was the cab roof. This is made from a piece of 10 thou nickel silver, from the waste area around a sheet of etches. This was formed to the curve by bending around a brass rod, tweaking it until it matched up to the cab front and rear profiles. It is not fully curved and should be horizontal for a bit at the sides. I achieved these flat sections by clamping it in the vice and bending with a steel rule. For the raised beading around the edges, I soldered on lengths of 0.3mm nickel silver wire. You see the roof from the top in the photo below: Although it would be possible to attach the roof permanently to the cab, I'm trying to avoid this to make painting easier. With my banking tank, I wasn't very happy with the fit of the roof, so this time I looked for something better. The solution is simple, and came from Simon Bolton's book Scratch-Building Model Railway Tank Locomotives. Two lengths of (0.3mm) wire are bent into the shape of a staple, and soldered to the underside of the roof. The projecting lengths of wire are bent outward a bit so that they hold the roof firmly in place, against the inside corners of the cab. It was actually quite tricky to line them up for soldering, but I managed by sticking the roof on to the cab with masking tape and tack soldering from underneath inside the cab. Then it was removed and the joints fully seamed with solder. The next two photos show the resulting roof in place on the loco. I don't have any prototype drawings or photos of the roof, so I don't know if there should be another strip across the middle or not. For the moment, I've left it off.
  6. Hopefully I won't disappoint anyone if I reveal that I don't mean interior details. Rather, I've added the spectacle plates, beading and vertical handrails on the outside of the cab. For the spectacles I made use of the etch I made previously for the Banking Tank. I already had a spare copy from which I had "borrowed" some other part during construction, so I thought I would make use of this. On the Banking Tank, the spectacles were part of half-etched overlays for the cab front and back, so I had to cut these out and carefully file/sand around them. Here you see this operation done for the first of the front rings: And here are all four. A major factor in deciding to reuse this etch was to save having to make the vertical bars across the rear spectacles by hand. I then soldered them in place on the outside of the cab front and rear You see them in the next two photos. Although not perfect, I think the result is neater than I could manage by fabricating them. Next up, I tackled the beading around the cab windows. This was made with 0.3mm nickel silver wire soldered on the outside of the body (a little subterfuge that works perfectly well). I toyed with using 0.2mm wire but decided it looked too thin. The photo below shows my technique, which is to solder one side, then bend around the corner, then solder the next side, and so on. This is what it looks like when the whole side is complete. I file the ends to length after attaching the handrails. Here's the finished article. The handrails are made from the same 0.3mm wire, cut over length, soldered behind the beading wire, then filed down to height. I find this simple method of construction is surprisingly effective, and it is not obvious at all that the beading is made from wire. The holes I had carefully drilled in the footplate for these handrails turned out to be in slightly the wrong place (of course), so I just soldered the bottom ends on top of the footplate.
  7. I had previously made the cylinders and motion but not actually mounted them to the chassis. After pondering how to do this for some time, I settled on the idea of a removable unit to mount both cylinders. As you see in the first picture, this is made from a piece of thin PCB, which will be horizontal on top of the chassis block, held in place by the body fixing screw. At each end I soldered pieces of brass tube that will hold the previously-made cylinders, increasing them to something like the correct diameter at the same time. Usually the cylinders would be mounted in a vertical plate going across the chassis, but this wasn't possible with my solid chassis block design. This photo shows the unit before drilling the fixing hole: As you see in the next photo, I filed a recess in the top of the chassis block to locate the PCB: And here is a view of the underside. Note the gaps to maintain electrical isolation. The cylinders are just held in here by friction, but I subsequently glued them in with Araldite. The cylinders in place with the motion attached: They're not actually fixed in place until you screw on the body: Now it's beginning to look like an engine! The pistons still need trimming to length at the front, and I need to tidy up the fronts of the cylinders somehow - perhaps with some thin discs stuck on. It was very satisfying to find that (with the motor detached) the loco rolls freely up and down a tilted length of track. But I have to admit that this wasn't achieved without a bit of effort. Firstly, the coupling rods were too tight, and I had to gradually open out the holes until the chassis would run freely. Then I found that there wasn't quite enough clearance between the slide bars and the rods, so I had to unsolder the brass tubes from the ends of the PCB and shift them outwards a bit further. Luckily there's no scale drawing looking at the loco front-on, so I had some freedom in the side-to-side positioning of the cylinders. Even so, I won't be able to fit crankpin washers on the front wheels. In fact, it still won't run up and down with the body properly in place, because the other crankpins haven't yet been trimmed and just foul the bottom of the valance. But it's getting there! The next job is to sort out the motor.
  8. After a delay while I ordered some suitable brass tube, I've finally added the front splashers. I didn't fancy trying to bore these out of brass bar, and in any case didn't have any of large enough diameter. Instead, I had the idea of using brass tube. First step was to solder a sheet of 5 thou brass to the end. This was then cut as close to the tube as possible with a Stanley knife. Then, it was chucked up in the lathe and turned down to the correct diameter, which was slightly less than the 1/2 inch of the K&S brass tube. This left quite a thin top to the splasher (also about 5 thou), but thick enough. The resulting hollow cylinder was parted off carefully with a parting tool. I made life tedious for myself by leaving the splasher rather over-width, mainly because I had no definite measurements for the width. This just meant additional filing later. The two splashers were then carefully cut from the same part using the piercing saw. (Apologies - I thought I had taken a photo of it at that stage!). The next photo shows my crude method for holding them in place for soldering, using a sliver of balsa from underneath. I actually cut off most of the balsa so that I could sit the loco upright on the bench, and then used a cocktail stick to hold the splasher from the top while bringing in the iron. One of them soldered on first time, and the other one came apart (Sod's law), necessitating a repair before trying again. I just about got away with it! Doing things properly I should have used different temperature solders, but I didn't have them. Here's one of the finished items. A bit of filler is needed at the tank end where too much of the thin front has broken away. I don't want to risk filling it with solder!
  9. Today I decided to turn the smokebox door from brass rod. I didn't have any hard dimensions to go by, so just estimated something from photographs. Here are a couple of photos of the workpiece in the lathe. I first drilled a 0.4mm hole in the end - this will take a piece of wire to hold the handles. I then had a go at forming the domed end. I didn't take a photo at that stage, so the first photo here shows me with a different tool installed that I have just used to remove the material behind the door, leaving a spigot. For this sort of operation I use a small parting tool that came with a holder to go in the tool post. I'm a bit of a novice with the lathe but find that this small, square-ended tool is often useful for 2mm scale turning operations, not only parting off. At this point I determined that the door was still too thick, so I worked on the rounded end again to thin it down. This time I did take a photo, so you can see my setup for doing this. These kind of rounded shapes are quite easy to do by hand with a graver. I don't have a purpose-made tool rest (the Sherline one is crazily expensive), so instead am resting the graver on a length of tool steel held in the tool post. Here's a picture of the graver - I got this a few months ago from https://www.eternaltools.com/carbide-gravers at the same time as ordering some piercing saw blades, and find it very nice to use. Certainly compared to the ground-down needle file that I used previously. Here's the back of the door after cutting off. You can see the 0.4mm hole inside the spigot. Then it was a case of soldering to the front of the smokebox, after first opening out the mounting hole. It turned out that this was no longer precisely in the centre (likely after my inadvertent repositioning of the smokebox front earlier), so I had to open out the hole further and position the door centrally by eye. Later in the day, after soldering this on, I looked at a different photo of the real thing and noticed that in Highland days that particular loco (at least) had a noticeable rim around the door. The picture I was looking at this morning didn't seem to show such a rim, so I hadn't included it in my turning. I think it is probably better now to leave it off rather than try to add it on untidily with wire or something. The hinges and handles/darts will be a task for another day.
  10. The next task was to fix the boiler/smokebox assembly to the chassis. Before doing so, I made a chunk of brass to fill the inside of the smokebox saddle, with the aim of giving something to tap a hole into for the chassis fixing screw. I initially intended to make this from insulating material, but didn't have any "engineering plastic" of a large enough size. I tried to make it from a lump of tufnol, but I realised that the space is actually pretty small, so opted to go for brass in the end as something more solid. I first cut a rectangular piece, filed it to size, then filed the seat for the boiler with a round file. (Apologies, I didn't remember to take a photo of this!). At this point I began a somewhat trying phase. Firstly. the saddle was soldered inside the smokebox, but the smokebox front shifted slightly in the process. On trying to fix that, the whole smokebox came off. So I had to clean it up and solder it all together again. Once I had this all attached, I did my best to file the base so that it sat flat on the footplate. But when I soldered the whole thing to the footplate, I found that the footplate was bent upward at the front, suggesting I had filed too much off the smokebox saddle. So it came off again and I inserted some shims of brass underneath, which then had to be cleaned up. Eventually I ended up as you see here. In this shot, the boiler has also been soldered to the tanks and cab front, and the excess solder cleaned up as best as I could. Next job was to drill various holes. Here you can see me drilling the chassis fixing hole through the smokebox saddle, from underneath. The footplate valance was useful for sitting on the jaws of the machine vice. I progressively drilled out the hole to 1mm, then used a pin vice to tap it by hand for the 12BA fixing screw. The next photo shows me drilling the holes on top of the boiler for the boiler "furniture". I measured them from the drawing. Somehow the hole for the chimney wandered to one side a bit on the initial 0.5mm drilling, but I was then able to drift it to central when drilling out to a larger radius. (I forget what radius - I'll need to determine this when I come to make the chimney!). The final step was to drill the holes for the handrail knobs in the smokebox and boiler side. This was also done on the Proxxon by holding the body sideways in the vice - I never have much luck drilling small (0.3mm) holes by hand! Here are some top and bottom views of the model in its current state. In the underside view I've left the body-to-chassis fixing screw standing proud. The screw at the rear end attaches the motor mount, and doesn't fix the body. I'm hopeful that a single screw will be sufficient.
  11. Due to a lack of forethought, I found that I hadn't made a large enough hole in the cab rear to accommodate the motor mount. I couldn't get in there with a file so I resorted to a burr in the minidrill to carefully remove the metal. Below you see the body in place on the chassis. If I were to use a similar motor mount in future, I would ensure that it was entirely in the bunker! You can't see it here, but I've also filed down the chassis block so that the body sits at the right height. Thanks to the footplate having a PCB layer underneath, the body is insulated from the side frames. The next job was to prepare the boiler and smokebox. These are made from brass tube, of diameters 8.73mm (11/32") and 9.5mm respectively. These two sizes are nicely telescopic, and a close enough match to the real thing for me. I first cut a length for the boiler, then used the piercing saw to remove the part that would otherwise interfere with the gears and motor. Incidentally, for cutting the tube to length I used the lathe, as I find it easier to get the end square compared filing/sanding after a saw cut. When cutting the smokebox it was a simple matter to cut a representation of the smaller diameter band at the inner end. The smokebox was slit across the bottom, and the previously prepared nickel silver front used to mark where to make the bends. The reverse curve in the smokebox "skirt" was bent using pliers, then it was soldered on to the boiler. The next photo shows my set up for doing this. Since I've never got around to making a proper wooden right-angle for this kind of job, I just rigged one up using a clothes peg that was sitting nearby. I found it useful to attach a piece of tufnol to the boiler with masking tape, so as to be able to hold and position it by hand and also to see more easily whether the smokebox was orientated correctly. The smokebox front was attached last, flat on the bench against the clothes peg. This photo shows it before cleaning up. Here's the boiler after cleaning up and shaping with emery sticks. (I left the smokebox front a little oversize originally to give me some wiggle-room): Finally for today, I soldered on the tank tops. I'm not attaching the boiler yet as it needs to be drilled for furniture and handrails, and I also need to sort out the body fixing hole and screw at the front.
  12. Thanks - there's still no guarantee that I finish it in four years, but I hoped that posting on here might guilt me into doing so!
  13. With the footplate ready I decided to press on with the basic body shell. First stage was to laminate two layers of 0.25mm nickel silver, again taken from the scrap surrounding an etched sheet. The pattern is stuck on with double-sided tape - I arranged the parts on the drawing to make use of one straight edge. The buffer beam is crossed out to remind me that I already made it! Before cutting out the pieces I drilled the various holes using the Proxxon. Then it was a case of cutting out roughly with the piercing saw (quick) and filing to the right shape (laborious - this is where etching saves time!). I used a brass tube of the planned boiler diameter to guide my filing of the large boiler holes - any imperfections will be filled with solder. Below you see the parts after desoldering the two layers and removing the pattern. The front and rear of the cab are not identical as only the front needs to house the boiler, so this was further filed after separation. Only one tank front and smokebox front are required, so I ended up with spares of these! From past experience, I know that getting the tank tops shaped to fit precisely up to the boiler as well as horizontal is a pain, so I soldered some n/s strips on the inside of the tank sides for them to sit on (made from 2mm Association plain rail). I also soldered similar strips on the cab front at each side, and also for the bunker rear to butt against. Assembly started by fixing the cab front to the footplate. I made a simple wooden base that fits inside the buffer beams to give me a flat base to work on, as the footplate is still a bit flimsy. Masking tape is useful for holding things in place (it doesn't seem to come loose when heated, unlike double-sided tape). Here the cab front is stuck to a tufnol block and located up to a measured line scribed on the footplate. Next, I attached one of the sides. In fact, the cab front came loose at this point and shifted, and I had to start over again, but I got there in the end. This is where designing an etch could make life easier by building in tabs and slots to locate all of the parts. In the next photo, I've added the cab rear and the tank front piece. And here is the other side attached. The last piece to be attached in this session was the rear of the bunker. In fact I had to cut this out separately as I didn't bother to draw it on the computer. It's just rectangular with a bend in. The metal strips made it easy to align, then I filed the top to the right height in situ. The tank tops will wait until the boiler is in place, but that's a task for another day.
  14. This week's progress has been on the footplate. First step was to cut out a rectangle of 0.8mm (single-sided) PCB, and a slightly larger one of 5 thou brass, and laminate these together with solder. The first photo shows the assembly on the Proxxon with the pattern attached by double-sided tape. I decided to mill out the cut-outs rather than using the piercing saw. I'm not sure this saved any time but it made it easier to get straight edges. And here is the resulting unit from underneath. Even more will need to be cut away to clear things like the coupling rods and (probably) motor, but I thought I would attach the body before I make it even more flimsier! Next step was to cut the buffer beams and valances from two sheets of (scrap) 10 thou nickel silver laminated together. I used the Proxxon to drill the three holes in a straight line before cutting out the buffer beam, but this time the parts were cut out with the piercing saw and filed laboriously to shape. The valances are very thin! This photo shows them before separating: Then it was a case of tinning the underside edges of the footplate top, and soldering them on. I wanted to achieve the effect of a slight lip where the footplate sticks out. The inside faces of the buffer beams and valances will need to be insulated, probably by glueing on Rizla paper. The final photo shows the footplate sitting loose on the chassis. In fact I need to remove some more material from the chassis to get it to sit at the right height, as well as from the footplate itself so that the coupling rod bosses clear the underside. The cab, tanks and boiler will be soldered to the footplate, and I want to get these in place before removing the final material from the footplate. I still need to drill the hole for the fixing screw at the front (right in the photo). Current thoughts are that I might make the smokebox saddle from solid brass and tap this to take the fixing screw, but we will see if this works out.
  15. Today I made the cylinders. Rummaging through my brass stock I found two concentric tubes, one whose inside diameter was a nice sliding fit on the 0.5mm piston rods, and another that fitted around it and had 2mm outside diameter. These two tubes will allow me to make a (coarse) representation of the housing/bearing where the piston rod enters. I had calculated that the whole thing needed to be about 4mm diameter, allowing 0.25mm for an outer wrapper (looking at prototype photos, it look like this is not cylindrical underneath, hence my choice of a separate wrapper). So I used the lathe to face and turn down a length of 5mm brass rod to 4mm, and to drill a 2mm hole through the centre. The two tubes were cut to length appropriately and soldered in, with a cocktail stick masking the hole in the end of the inner tube. The photo below shows me filing a slot in the top of one of the cylinders to take the slidebar. I started the slot with the piercing saw and then cut the rest with a thin file. This was a case of trying the slidebar in place along with the valve gear, filing more and more until it was nice and straight at the correct height. I then soldered in the slidebars to arrive here: And finally, with the valve gear in place: I'm hoping that there is sufficient motion in the piston rod, but if not I may need to carefully file down the bearings in the end of the cylinders. I still need to cut the piston rods to length so that they don't stick out of the front of the cylinders, as you can see. Next I have to attach the cylinders to the frames, and holding them in place shows that they need to be set out quite a long way from the frame. I think I will do this with pieces of brass - watch this space!
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