bertiedog Posted February 4, 2011 Author Share Posted February 4, 2011 Coat of grey to check the match of parts replaced, it will be washed off to do more assembly. The firebox matches well with the K's parts, and firebox shape seems correct to photos of the real thing. Link to post Share on other sites More sharing options...
Horsetan Posted February 4, 2011 Share Posted February 4, 2011 The backhead from the ROD version of the 2800 at Didcot.... Errm, Stephen. The ROD did cover the 43xx, and Didcot's 5322 is in ROD (WW1) colours at present. The photo you've shown is of 5322. Didcot have never attempted - to the best of my knowledge - to present a 28xx/2884 as being in ROD livery. ....Two LH firebox sides was bad luck. Stephen.... I can match this. I once picked up a "Steamcast" kit by MTK. It was for the BR Std.4 Mogul, plus BR1B tender. The tender parts included two left sides Link to post Share on other sites More sharing options...
bertiedog Posted February 5, 2011 Author Share Posted February 5, 2011 I had meant 4300 for the Didcot Mogul, it was wrongly captioned. and is the right type back head for the Mogul. There is no floor or detail in the cab as designed, the bottom has a nut to take the bolt that retains the chassis, but the level of the floor is high enough to cover this completely with a brass floor. The wheels need clearance, the rear of the splashers are under the floor on the real loco, but the bigger 00 flanges may just foul the floor, and clearances must be checked carefully. I read the line about the tender parts till the MTK mention, enough said? K's were way ahead of MTK on casting quality and lack of errors. There's a bit of correction and lining up of the cylinders on the cast whitemetal chassis mounts, the chassis will be prepared first, and then the cylinders temporarily attached to the body with superglue, and the chassis bolted on in the correct position, and then the joints can be flooded with low melt solder, which will lock the parts in the correct position, but still allow unbolting from the chassis. A thin brass plate will be added to support the slidebar hanger, soldered to the bars and resting under the footplate to give extra support to the cast hangers The chassis needs accurate assembly, and the axle holes drilled out to take bearings that will be running in slots to allow springing. At the moment the intention is to drive the middle axle, with the motor behind the middle axle. I have a small five pole motor which will fit the space with a flywheel. It should just be powerful enough for the loco, there is no intention for long or heavy running. The driving wheels can be prepared outside the chassis and drop in complete with the bearings. It will need a keeper plate added to the bottom of the chassis, which may need extra frame spacers added to support it. Stephen. Link to post Share on other sites More sharing options...
bertiedog Posted February 6, 2011 Author Share Posted February 6, 2011 The Cylinders with brass strengthening plates, and packing in the middle, the castings are K's, which are open backed cylinders. The drain cocks and pipes have to be drilled for and added in brass Cylinders under the footplate. the brass plate barely shows under the cast footplate, but adds strength to a weak area of support for the hangers. Link to post Share on other sites More sharing options...
bertiedog Posted February 6, 2011 Author Share Posted February 6, 2011 Start of clean up for the cab area, K's provide no interior detail, or backhead, or even a floor. The new floor is brass, covering the retaining nut for the chassis, with a face piece added for the vertical surface, all tinned in lead free tin solder, before soldering on with low melt solder. The ribs on each side of the front cab plate can have the pipes added, in fuse wire, as if they are the lubricator feeds, and a brass backhead added, with gauges etc. The area over the flanges will have to be left for the moment to see what clearances are involved with the sprung wheels, but it looks like two plates are all that's needed just like the real cab floor. The springing will be minimal at about 1mm movement. I think K's intention for the drawbar to the tender was to use the rear retaining chassis bolt, but this is rather crude, and a brass plate with a steel pin will be added under the drag beam under the new floor. Stephen Link to post Share on other sites More sharing options...
bertiedog Posted February 6, 2011 Author Share Posted February 6, 2011 It looks like the floor is above the wheels arch , so a further plate can be added to the floor to get clearances. Link to post Share on other sites More sharing options...
RMweb Premium Blandford1969 Posted February 12, 2011 RMweb Premium Share Posted February 12, 2011 It looks like the floor is above the wheels arch , so a further plate can be added to the floor to get clearances. You are quite right on this, I was at Higley today measuring for 82045 and took the time to look at the mogul. The washouts are exactly as you have done. The floor is flat and does not have splashers. The one thing i remembered when looking at it is the atomiser is a coil rather than as shown in your photo, but that could be an SVR thing. Really enjoying seeing you make a loveley engine out of a basic kit. Best wishes Duncan Link to post Share on other sites More sharing options...
RMweb Gold The Stationmaster Posted February 12, 2011 RMweb Gold Share Posted February 12, 2011 You are quite right on this, I was at Higley today measuring for 82045 and took the time to look at the mogul. The washouts are exactly as you have done. The floor is flat and does not have splashers. The one thing i remembered when looking at it is the atomiser is a coil rather than as shown in your photo, but that could be an SVR thing. Duncan The atomiser usually was a coil - although there might have been exceptions (or possibly an earlier idea of arranging it?). Link to post Share on other sites More sharing options...
bertiedog Posted February 22, 2011 Author Share Posted February 22, 2011 Major change of build plan, the frames are being changed, as careful checking showed the drilled outer holes are not aligned parallel to the bottom or top of the frame, and are not a match to the etched nickel silver side rods. The frame was also short in length, stopping short of the drawbar under the cab, instead of reaching the drawbar at the back of the cab. The filled in backs of the steps visually cover the short frame, but it is noticeable at an angle. The new frame retains the cast whitemetal extension around the cylinders, but that also is short of touching the front footplate curve, and needs a small packing piece added, I have changed to a box section brass extrusion, which is a fraction thicker brass, but still takes the spacers for body mounting and motor retention, The axle holes will be drilled to match the rods, by using them to drill pilot holes, opened up with drills and reamers. The spacers are changed to square section, bar the support one for the cylinders, which fit into the casting to give firm mounting, when bolted on with a brass 8BA nut and bolt. The box section brass was sawn to the depth required, which is now about scale depth, as the K's frames were also too shallow for the correct dimensions, leaving a lot of daylight under the frames and wheels. . One edge of the box remains, to act as bottom dust cover, but it will have apertures for the gearbox etc., milled into it. The top is open, but with the spacers put in with 10 thou brass sheet washers to get an exact match to the frame width, and keep everything parallel. So far the Keyser wheels seem to be usable, they test as true etc., but Alan Gibson do replacements if needed further into the work. I do not personally find the Gibson crankpins so good as plainer types, and the K;s are quite all right, moulded firmly into the wheels, and all have the same throw! K's have etched the holes in the rods accurately, but the middle hole is a larger diameter, so the outer ones will be opened up to match, and all fitted with brass bushes to get a close fit. I had thought's of springing the locomotive, but I think it will be un-sprung, at least at first, as new side rods would be needed to allow springing, so it will rely on play in the axles at first. As long as the wheels are reasonably concentric, and the chassis accurate, then un-sprung works well in OO, but I would not risk it in P4 The tender is difficult to spring with the dummy axleboxes rigid, and also difficult to assemble as the wheels have to be fitted during assembly, to get them into the bearings. The alternative approach is a secondary inside bearing frame for the tender, and this is by far the better option, allowing ease of assembly, and painting etc. The only other option is split axles, with a connecting sleeve, allowing the wheel to fitted whilst the axle is contracted in size, and then Loctited into place at correct back to back. But this also poses painting problems, as once in they cannot be removed easily. 2 Link to post Share on other sites More sharing options...
bertiedog Posted February 23, 2011 Author Share Posted February 23, 2011 The parts for the replacement chassis, with the cylinders fitted with plates to support the guidebar hangers. A choice of possible motors including the K's , which will need metal bearings fitted if used, which is unlikely as it cannot take a flywheel. The other motors are, a Tenshodo 5 pole, and an un-branded 5 pole skewed slot motor, of which type I have used before. Both the smaller motors will easily take a small flywheel, and still fit the firebox. The five pole in the frames has no mounting holes, so will need a frame to attach it. The gears appear usable, they are concentric, although the worm has rather shallow tooth form, and it may need a new one made. Next job is the drilling of the axles holes accurately to the rods. Stephen. 2 Link to post Share on other sites More sharing options...
bertiedog Posted February 23, 2011 Author Share Posted February 23, 2011 Shot of the chassis in place with new depth to near scale position, K's frame was not deep enough by almost 3mm, placing the axles too near the edge of the frames. The new material is wider and thicker as well, but it still takes the spacers for mounting positions 1 Link to post Share on other sites More sharing options...
bertiedog Posted February 23, 2011 Author Share Posted February 23, 2011 The K's motor for reference, usable if the plastic bearings are replaced, and a double length shaft fitted. The armature and brush gear work, but without alterations the poles can rub the armature as the bearings wear, and they do have a tendency to burn out under load. They can be rewound quite easily. The gears appear usable, they are concentric and fit the axles and shaft tight, although the worm will require a sleeve to work with smaller metric shafts on the five pole motors. The tooth form is a bit wrong on the worm, but it will be run in in a frame with fine abrasive bedding compound to get the teeth to bed in correctly, and it should then be fine. If the bedding fails then a steel worm can be turned to match. Stephen 1 Link to post Share on other sites More sharing options...
Gordon A Posted February 23, 2011 Share Posted February 23, 2011 The build looks very nice. I may have missed the point of the build, but why use antiquated motors and gear drive? I would reccomend a High Level Slimline 2 stage gearbox in the 50+ to 1 range with a modern skew wound Mashima which would give you greater control of the locos running. Gordon A Bristol Link to post Share on other sites More sharing options...
bertiedog Posted February 23, 2011 Author Share Posted February 23, 2011 Cost......the gears are all right and the five pole motors are fine, and already available, and I don't really like plastic intermediate gears. Ultrascale do brass helical, but delivery is long. The K's motor will not be used in this loco, it may be used in a Terrier on the way from Ebay, which has one already, but with these K's motors a spare is a good plan. In fact if re-wound and fitted with bearings the K's are quite OK. the commutator is sound, and the three pole easy to do the winding on. K's appear to have used the wrong grade of enamel insulated wire, and got nicks as the winding was done, leading to shorting turns and over heating, which melted the bearings. which if worn, could allow the armature to foul the magnets. When they first came out I re-wound one with a star wind, finer wire, and more turns, and fitted ballraces, still got the motor in full running order, never gave any trouble. It is not a bad design, just poorly assembled, with lousy bearings. With the proper gearbox added to the smaller motors they will be fine, I think the larger one is better , with a flywheel fitted as well, the 30:1 gear should function well. The only weight it will haul is itself, plus a few wagons or a couple of coaches, and that is well within the range of the motors. For heavier duty use I would change to a coreless Maxon motor with a tower gearbox as per Portescap, as when mounted higher the usually bigger Maxon types will still fit above the frames. Stephen. Link to post Share on other sites More sharing options...
hayfield Posted February 24, 2011 Share Posted February 24, 2011 Further searching on the net only gives O gauge or gauge one parts,, does anybody do a range of lost wax parts apart from Gibson's range.? Stephen, I need to replace some and I was told last weekend that Markits may now do one that would fit in brass. 1 Link to post Share on other sites More sharing options...
RMweb Gold RedgateModels Posted February 24, 2011 RMweb Gold Share Posted February 24, 2011 I may have missed the point of the build, but why use antiquated motors and gear drive? He likes the challenge too Link to post Share on other sites More sharing options...
bertiedog Posted February 28, 2011 Author Share Posted February 28, 2011 New Brass channel Mogul chassis, awaiting bronze bushes for the 1/8th inch bearings, to fit into 4mm holes, co-ordinate drilled in a milling machine for accuracy. They will be soldered into place with the etched rods for final alignment. The flat head frame spacer bolts have been screwed flush with the frame surface by counter boring a recess the depth of the head into the brass sideframe. Access holes are required for the bolts though the spacers, and holes will have to be added to the sideframes for the brake shoes supports. The chassis is being built rigid at first, may be sprung later. The cut out is for the gear box, with a cover over the aperture. The rear is adjusted to scale size to take the drawbar. The Wheels were about to be fitted, but two axles went missing, replacements being sorted, or possibly other wheels, as the K's are a bit problematic , the plastic is quite soft, and I am not sure about long term reliability. They are accurate within reason, certainly if sprung, which helps with any eccentricity. Link to post Share on other sites More sharing options...
bertiedog Posted February 28, 2011 Author Share Posted February 28, 2011 Plan B on the wheels, changing from the K's to Hamblings, they are a bit larger overall, 24mm, instead of 23mm, but will need the flange reduced etc., upon machining anyway, to RP-25 height. They are un-machined 24mm mouldings in brass and Bakelite, moulded about 40 years ago, but in prefect condition. They can be machined to fit un-splined stub axles, which will allow adjustment of the quartering, and be retained by loctite or epoxy. From long experience with these wheels they are accurate and true, but the throw needs increasing and better crankpins fitted. The advantage over the K's is they cannot rust, and have a firm metal centre, which keeps them running true. I'll machine up a set plus spares and see whether they can be attached with a retaining screw, but I suspect the glued fit would be best for strength. I have machined them to fit Romford axles before now, it needs packing washers on the shorter axle to get the back to back correct. It may be possible to use a 10 BA bolt to secure the boss to the axle, it would make them removable and adjustable for quartering. Stephen. 1 Link to post Share on other sites More sharing options...
bertiedog Posted March 1, 2011 Author Share Posted March 1, 2011 The wheels prove un-machinable in a three jaw chuck, not unexpected, they distort at the grip pressure required, so making a split collet to take the entire wheel to enable it to fit the three jaw whilst giving an even and accurate grip, both for machining the back and the front as well. Stephen. Link to post Share on other sites More sharing options...
bertiedog Posted March 1, 2011 Author Share Posted March 1, 2011 The split collet in bronze, that is required to machine the wheels accurately. This one takes the wheel face inwards, and allows facing and drilling the centre hole with complete accuracy. It fits the lathes three jaw chuck, and runs at under a thou out on the 24mm diameter. I will do some spare as well as the six needed, the centre hole does not matter, the axles are machined to match. 1 Link to post Share on other sites More sharing options...
hayfield Posted March 1, 2011 Share Posted March 1, 2011 Bertidog, that was quick. I have just had some Hamblings 24mm drivers arrive in the post, I have at least 1 if not more locos with these wheels and have some in my wheel box for future use. Is it worth drilling out the K's wheels to take standard 1/8th axle rods? Link to post Share on other sites More sharing options...
bertiedog Posted March 1, 2011 Author Share Posted March 1, 2011 The K's wheels could be re-drilled, but they would be best with a brass bush inserted, with a backing flange, to provide a firm metal bush to drill etc., However there is a point with K's to make, the rims may be OK to grip, but the spokes can be pushed out by the drilling pressure, so a centre stop is required to bear on the inserted bush to do the re-drilling. The bush must be epoxied into the ABS plastic boss, the surfaces roughened a bit. The wheel would then be put in a split collet and a pusher stop advanced to touch the bush so that the force bears on the stop, not the wheels spokes. I will complete the Hamblings set, and then modify the K's in the same way with brass bushes for comparison. The small nuisance of the Hamblings is the brass colour, but it is rust proof, unlike the steel K's wheels. The Bakelite centres of the Hamblings will resist the drilling easily, and they are quite heat proof for medium 148o solder, should "shorting" be required. Link to post Share on other sites More sharing options...
coachmann Posted March 1, 2011 Share Posted March 1, 2011 Must say I'm suprised you were even considering using K's wheels, but now Hamblings? They were the wooden spoon of drivers even in the early 1960s. Carry on like this and I'll be a nervous wreck.........Fit romfords man.... Link to post Share on other sites More sharing options...
bertiedog Posted March 1, 2011 Author Share Posted March 1, 2011 Romfords modern versions from Markits are very expensive, and not as accurate as the lathe turned Hamblings, only bad when miss machined. The shot shows re profiled to RP- 25 on a damaged centred sample, still able to take a new bush if required. The spokes still have to be cleaned up from the back, and thinned down. Link to post Share on other sites More sharing options...
multiprinter Posted March 1, 2011 Share Posted March 1, 2011 Why did Hamblings persist with brass tyres rather than nickel silver? I can understand them not using steel in case it rusted. Link to post Share on other sites More sharing options...
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