Ian_C's workbench - P4 and S7 allsorts

Discussion in 'Workbenches, including workshop techniques.' started by Ian_C, 21 May 2017.

  1. Threadmark: Works plates and Santa's coming
    Ian_C

    Ian_C Western Thunderer

    Hmmm. The only photo I can find of 48142 at about the right period, shows that there wasn't a plate fitted to the RH frame. Although it looks like there's a trace of where one used to be. There's an electrification flash fitted partly over where it would have been. My assumption is that there's a plate fitted on the LH frame, although that's not visible in the photo. I note that the next Irwell 'Book of the 8F' is out now, and it does cover 8142. I put the book on my list to Santa, and I have been quite good, so maybe more info will be forthcoming. I mean, how do you get eight reindeer and a high cube sleigh onto this roof? And some of the old tiles are quite fragile... Whereas Gresley chose some excellent racehorse names for his pacifics, Santa seems not to have given it much thought when he was handing out names for reindeer. I suppose 'Comet' wasn't so bad - 45735.
     
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  2. adrian

    adrian Flying Squad

    Thanks for the updates - you're setting a new bench mark here!

    For one moment I thought it was Christmas
    but then had a quick look - Part 2 covers 48126 to 48297. :( Hopefully 48388 will be in part 3.
     
  3. daifly

    daifly Western Thunderer

    The Highley 8F is 48773 - you might have to wait for part 6 for that one!
     
  4. Threadmark: Happy Christmas - and Santa brings a new book
    Ian_C

    Ian_C Western Thunderer

    Well, I must have been good enough, as there was a copy of The Book of the Stanier 8F 2-8-0s - Part Two: Wartime Engines 48126-48297 - Irwell Press, ISBN 978-1-911262-28-2 under the Christmas tree yesterday morning. If you're into Stanier locomotives and 8Fs in particular then it's highly recommended (along with Part One).

    Amongst the other delights there are two new photos of 48142, and some gaps in the history filled in. You'd imagine it did some work at Toton, as it subsequently moved to Annesley and then Kirkby. One of the photos shows it out working in 1966 as a Kirkby loco. So Toton wasn't the end of the line for 48142.

    None the wiser on works plates though. 1965 = no plate on RH frame. 1966 = no plate on LH frame. Early 1960's at Cricklewood = definitely a plate on the RH frame (and electrification flash in a different position, not covering plate location). Is it possible that from 1965 onwards it carried no works plate?

    Anyway, Happy Christmas to all. And if I don't post again over the holiday period, Happy New Year as well. In spite of everything, is it too much to hope for a little sanity and peace in 2020?
     
    Rob Pulham likes this.
  5. richard carr

    richard carr Western Thunderer

    Ian

    Those are some lovely wind deflectors but wouldn't it have been better to add the glass after painting.

    Richard
     
  6. Threadmark: Deflector glass & paint
    Ian_C

    Ian_C Western Thunderer

    Yes, I will. They're just temporarily in at the moment so I can see what I've ended up with.
     
  7. Threadmark: Cab doors, with added files, flux and RSU
    Ian_C

    Ian_C Western Thunderer

    The BOT8Fs Part 2 from Irwell serendititiously has a couple of excellent close up photos of cab doors on 48133 and 48131. I'd turn them into art prints and hang them on the wall if I could. Browsing lots of 8F photos reveals that there were several minor variations of the cab doors, mostly to do with rivet positions and the extent of beading (if it is really beading, it looks like wooden wear strips in some photos) around the edges. Since I've no idea which details were present on 48142, I've chosen a combination that I'm happy to model.

    Comparison of drawing dimensions and photos with the etched kit parts persuaded me to make some replacements from scratch. The signature features on the doors are the hinges. They're very chunky and held together with battleship rivets. The first job was to sketch the hinge parts in CAD and establish sizes and rivet positions. Since they're such small parts there's not chance of adding rivets accurately to finished hinges. Therefore several hinge rivet patterns were pressed into a scrap of NS using the (t)rusty GW rivet press. It doesn't get used much, and hardly ever using the graduated slides, but this time it was just the right tool for the job. It doesn't take many rivets before I start wondering if there's a better way. And waddaya know, there's dude in the US who has actually made a CNC rivet press...
    Computer Controlled Rivet Embossing Machine
    GW rivet cab door.jpg

    Door blanks were cut from more NS (0.27mm I think - didn't measure, just felt about right), and we have some parts to start work.
    cab door parts 1.jpg

    The cutting of hinges from the pre-rivetted strips was a trial, and you need several of them. I made a few spares of course - there'll soon be enough parts in the vacuum cleaner to build another loco. The vertical strips appear to be a half round section, and they were made from brass wire filed half flat. All the fussy soldering was done with the RSU and tiny chips of 145 degree solder. Here's one door compared with the kit parts. Scribe lines are regrettably heavy, hopefully I can buff them out.
    cab door compare.jpg

    There's some vague provision on the kit parts to hinge the doors using (I assume) wire. They can't be rigidly mounted to the cab because the rear edges will bear on the tender (...yeah...the tender eh?...) at some point and there will be relative movement between loco and tender to accommodate. Low wattage light bulb moment - I used some phosphor bronze strip behind the doors to act as springy hinges. The strip is only spot soldered at the rear end and the middle of the forward door section. That leaves a reasonable length of strip free to flex. Sorry about those lower door rivets - freehand innit?
    door hinges 1.jpg

    I discovered at this point that the hinge positions I'd estimated were a little at odds with those of the kit. Since there's an etched notch in the cab wing plate for the door hinges I need to make a wing plate overlay to cover them up.
    wing plate 1.jpg

    Having fitted the wing plate overlays (and neglected the opportunity to add some missing rivets to them before soldering - duh!), the door assemblies can be fitted to the cab.
    cab door fitted 1.jpg

    The downside to this approach is that the hinge strips show inside the cab. Hopefully they won't be too sore thumb when the loco's painted and the crew are drawing attention to themselves. They spring inboards and return quite nicely with little force needed. Another potential problem is that the loco body now needs careful handling to avoid damaging the door hinges. There's not a lot left to do on the loco body now, so hopefully they'll survive.
    door hinges 2.jpg

    Bonus material - maybe.

    Files. One great distraction activity, when I'm faced with a modelling task that I'm not too enthusiastic about, is wasting time on You Tube pretending to look for useful information. For once, at least, it bore fruit. I came across some horological wisdom on files and filing here... . Since we tend to do a lot of filing it's worth a watch. Something I'd not thought about before is 'safe edges' on files. Not safe as in 'occupational health & safety', but safe as in a surface that won't cut. Armed with that nugget of information, I took the small Vallorbe escapement file out the the workshop and ground one of the edges smooth on the cutter grinder. Heresy, I know. It made filing some of the hinge internal corners a whole lot easier. Rubbish photo, but you get the point. Recommended.
    file safe edge 1.jpg

    Flux and soldering cleanliness. I pay a reasonable amount of attention to cleaning up parts before soldering. Wet & dry, scratch brushes, wiping clean with IPA, and all that. I use Fluxite paste flux for a lot of work - stays where it's put, good fluxing action and is easy enough to clean off afterwards. The tin of Fluxite I have was inherited from my late father, and goodness knows how long he'd had it! I remember it being part of his tool kit when I was a little boy. It occurred to me that the murky dark brown paste in the bottom of the tin was actually quite filthy. Filled with grit, solder blobs, dust and 60 years+ of accumulated workbench detritus. I guess I'm emotionally attached to the tin, so rather that throw it away I cleaned it out and refilled it with fresh paste from a new tin of Fluxite (they still make the stuff). Surprisingly fresh Fluxite is a pale yellowy colour, not a dark brown. Unsurprisingly fresh, clean flux works much better than old, mucky, degraded flux. Who have thought it?

    RSU electrodes. I have an old Exactoscale RSU. Bought it on an impulse at a show a long time ago. Less than full price, and quite possibly Bernard Weller's prototype unit! Utterly unsophisticated, but it works well. I also acquired a small plastic bag with a dozen or so copper coated carbon electrodes for the probe. They don't get used up very fast so they've lasted a long time. They're not the sort of thing you come across when you're out shopping, so when I stumbled across some on eBay I thought I'd restock. The eBay electrodes turned out to be a revelation. They're much denser and harder that the Exacto originals (closer to the charcoal end of the spectrum!), and that makes them much easier to shape to a point and much less prone to crumble in use. It's made soldering of tiny details much easier with a properly pointy point. Wish I 'd discovered that years ago.
     
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  8. michl080

    michl080 Western Thunderer

    Ian, interesting, do you mind sharing your ebay link?

    I had to restock my RSU electrodes recently and bought Kohleelektroden spitz Ø 6,5 x 305, bis 400A, 50 Stück | eBay these at ebay. Looks like these things are called "gouging electrodes". They are quite hard, but I can use a pencil sharpener to sharpen them.

    I have a life time supply now :)

    If you would be interested to compare, i could send you some.

    Michael
     
  9. P A D

    P A D Western Thunderer

    Superb Ian!
    Both the modelling and the tips, especially the safe edge on files. Looks like the grinder will be getting some use.

    Cheers,
    Peter
     
  10. Tim Watson

    Tim Watson Western Thunderer

    Interesting video. I have always been a user of safe edged files & the techniques espoused. Not sure where I learnt them...

    Tim
     
  11. Phil O

    Phil O Western Thunderer

    When I need replacement carbon rods I go to my local welding supplier and get gouging rods, the last time he gave me the last two he had. The only problem is that the copper coating is a bit thick and so I have to put it in the lathe and thin it down, sometimes it peels off, but hasn't affected operation.
     
  12. Ian_C

    Ian_C Western Thunderer

    I'd love to share, but like a lot of eBay miracle purchases, I can never find the stuff again. Yes, I binned the email when the package was delivered. Gouging electrodes eh? You learn something new every day - thanks. If I turned the old RSU up to maximum / maximum they probably would be gouging electrodes! I'd love to try one. I'll DM you.
     
  13. Threadmark: Sweet and tender romance...
    Ian_C

    Ian_C Western Thunderer

    ...The Bangles, 2011.

    Yes, finally I've made a start on the tender. There are still a few tidy up jobs on the loco, but I'm not in the mood right now and want to press on. I'm going to put the electrical pick ups on the tender so it helps a lot if all of the wheels contact the rails at the same time. As with the loco, the compensation arrangement on the tender is goofy. It's what you'd call 'statically indeterminate' if you wanted to impress somebody with your engineering knowledge. Or, to use the popular furniture analogy, if compensation is meant to give you the equivalent of a three legged stool on the uneven kitchen floor, the kit gives you a four legged chair that rocks from corner to corner. There's no cross chassis compensation. I'd imagined that I'd simply (!) redesign the inner chassis with sprung axle boxes or CSB...or something. Plus I was going to use insulated split axles and avoid wiper contacts. Ambition is an admirable thing. When I looked at the chassis etches and the instructions it was hard to see how it all goes together and comes apart again with brake linkages and water scoop gear strewn all over. Overwhelmed. Where on earth do you start?

    I've decided to build according to the instructions up to the point I can see how all the gubbins fits together, then work out what changes I want to make. The tender instructions are patchy (but Mr MOK made that clear at time of purchase, so no surprises). The David Coulshed (circulating somewhere on WT) annotated version adds some useful notes and is worth obtaining. The Wild Swan 8F Loco Profile has no drawings of the 4,000 gallon tender, but they are present in Loco Profile 5 - The Mixed Traffic Class 5s - Nos. 5000-5224.

    The initial build offers a respite from the mental toil of design and scratchbuild, and substitutes the tedium of filing off etch cusps.
    outer chassis parts.jpg

    The MOK tab & slot fabrication makes life very easy. There are a couple of misplaced tabs on one of the chassis end sub assemblies but it's easy enough to file them off and position the parts by eye. Very quickly you get to this stage...
    outer chassis assy.jpg

    Naturally there's a puzzle to solve. The lower crossmembers really do have to be removable to allow the fitting and removal of the inner working chassis. It took me a while to realise that one crossmember is flanges up and the other is flanges down. I discovered this when examining the drawings in the Wild Swan book, but it was stated in the instructions if I'd cared to read them! How to secure them without fasteners showing is the challenge. I don't know what the kit design intention was, but this is my solution...
    chassis x member pics.jpg
    There didn't seem to be any point in using all of the fixing points and doubling up the amount of work.

    The inner chassis is the next job, along with a look at the compensation problem.

    This episode brought to you with help from Bedsofaland, 9 Lazy 9, 2010
    Screenshot 2020-01-27 at 21.44.30.png
     
  14. adrian

    adrian Flying Squad

    I'd be very interested to see your plans/solution. I've been mulling over exactly the same problem for the same kit as I have a similar opinion on the rocking "suspension" system as designed. I'm sure it works fine but it just doesn't quite compare with full suspension.

    Likewise I'd like to build in CSB for full suspension, insulated split axles for current collection. At the moment I'm experimenting with an insulated axlebox fitted with a ball-race. However it does require a 4mm diameter axle. Not too much of a problem as I have a set of Mark Wood wheel castings so I can work my own diameter on the axles, it's just experimenting with the sizes for the telescopic axles and insulation.
     
  15. Ian_C

    Ian_C Western Thunderer

    Really, it doesn't work fine. It can't. I guess it'll stay on the rails so long as no wheel lifts more than a flange depth. If you have track that's level to a very high standard maybe it'll never be an issue. I'd much prefer all wheels in contact and an equitable weight distribution. It's the same with the loco. I added some secondary springs to one pair of comp beams just to keep the wheels in contact. It's sort of OK but it still irks me. I wish I'd paused to work out a CSB installation.

    Right now on the tender I'm retreating a bit from the ultimate solution. The path of least resistance might be to keep the comp beams as they are and provide cross chassis compensation on the front axle. And I may just chicken out and use wiper contacts on the wheel tyres. I have Slaters wheels for the tender, so there would be the extra complication of shorting from tyre to axle if I wanted to pick up from there. It's one of those jobs that looks simple, until you get to grips with it, and then it turns out to be really difficult.
     
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  16. Threadmark: Tender compensation beams - minor mods
    Ian_C

    Ian_C Western Thunderer

    On the journey towards a fully compensated tender chassis, there were a few things I wanted to change on the compensation beams supplied on the kit. So far as I can tell it's not possible to remove the beams once the inner chassis is assembled. At least I couldn't work out how to do it. Once the side control tabs on the chassis etch (see a photo below) are bent into the final position to compensating beams are locked in. Sure, you can unbend the tabs but the half etch bend line won't withstand many bends before it breaks. Here's a way of providing an equivalent level of control of the beams and be able to dismantle them without bending or breaking anything.

    t comp beam parts.jpg
    The beam pivot in the kit is a length of 2mm diameter rod that's soldered in position across the chassis once all is assembled. I replaced that with a length of 2mm rod with a head soldered on one end and a 12BA retaining screw and washer threaded into the other. The pivot holes in the beams were opened out to 4mm diameter and some large top hat bushes soldered in. The bushes are a close working fit over the pivot rod, and provide the necessary side control of the beams. The beams are a double thickness laminate of 0.6mm N/S and plenty stiff enough laterally themselves.

    t comp beam assy 1.jpg
    The length of the bushes was calculated have them fit end to end across the inside of the chassis with a small clearance to allow them to rotate freely. The length of the pivot rod has to be adjusted carefully so that when the screw is tightened it doesn't pull the chassis in and pinch the bushes. Now it all goes together and comes apart easily enough.

    t comp beam assy 2.jpg
    Here's the offending bendy tag wotsit. The original intent is that once bent in to 90 degrees it just rubs the inside of the compensating beam and provides side control of the beam and axle bearing, which the original small pivot bush wasn't able to do. Once bent, there's no way of removing the beams. The outer diameter of the bushes is 4mm and I'm hoping that they don't clash with something unforeseen in the brake linkage or the water scoop gear. Flying blind somewhat...

    Some useful reading here regarding compensation and suspension in general....

    LOCOMOTIVE COMPENSATION by Brian Clapperton, ABC Gears
    http://www.abcgears.co.uk/abc_gears_-_loco_suspension.pdf

    The principles of model locomotive suspension
    by Russ Elliott
    Scalefour Digest 41.0 'The principles of model locomotive suspension'
    Part of the Scalefour Digest, but principles applicable to any scale.

    Screenshot 2020-02-02 at 13.28.50.png
    In the background right now - We are but hunks of wood - Little People 2012
     
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  17. Threadmark: Tender rolling chassis and compensating the front axle
    Ian_C

    Ian_C Western Thunderer

    The front axle sits in an awkward place relative to the MOK kit chassis structure. It wasn't immediately obvious how to fit a cross compensation beam in without making changes to a lot of chassis parts. Another of those jobs that looks straightforward, but turns out not to be. The problem was modelled on CAD, and after many schemes I ended up with this...
    axle comp CAD 1.JPG

    Because of the chassis structure in front of the axle (not modelled) a clevis arrangement can't practically be fitted in, so a bearing block pivoting on a cantilevered pin was the solution. The mounting block (yellow) locates up against a chassis cross member and is fixed with a couple of 10BA screws.The design was broken down into a few simple to make parts.
    front axle parts.jpg
    All from brass bar apart from the steel pivot pin. The pin is drilled through and threaded 12BA,and is a press fit into the mounting block. The axle bearing tube and axle pivot block were designed to self locate for soldering together. The reduced diameter section of the axle tube is 6.0mm so that the corresponding concave profile in the mating block can be cut with a 6mm ball end mill.

    sub assys.jpg
    The axle tube was soldered to the pivot block. There's plenty of joint area so soft solder is fine. The tube was reamed through 3/16" to match the Slaters axle, and some of the centre section was milled away to reduce a drag (depending on where you shop, every little helps). Two small holes were drilled in the ends of the bearing tube for oiling the bearing (can't see them in this photo). A custom washer was turned for the retaining screw.

    axle assy 1.jpg axle assy 2.jpg
    Here it is sub-assembled, front and rear views. The axle oscillation is limited by the distance between the two blocks. Doesn't really need to be that much, but y'know, round numbers in CAD. Pretty obvious how it works. Ignore the small aluminium block, that's just so the wheels clear the deck.

    assembled 1.jpg
    The point of no return now! The existing bearing lugs are cut off (alongside on the cutting mat) and the holes for fixing the mounting block are drilled in the chassis. The assembly is fixed to the chassis using two 10BA screws.

    assembled 2.jpg
    There's more etched gubbins to be soldered to this end of the chassis later. The tabs on the mating etched parts that locate in the slots in the crossmember will need to be shortened so that they don't project through and touch the mounting block behind.

    rolling chassis 1.jpg
    Blimey! What a performance! But I now have a rolling chassis that keeps all six wheels on the railhead. In passing, there's a huge amount of clearance between the back of the wheels and the outside of the bearings on the two trailing axles. Some spacers needed next time I visit the lathe.
     
  18. Threadmark: Tender water scoop gear
    Ian_C

    Ian_C Western Thunderer

    Yes, the water scoop gear turned out to be quite a challenge. Considering that most of the scoop gear and brake gear lurks in the dark void under the chassis it's represented in the MOK kit in considerable detail. The theory of authentic clutter dictates that if it's visible in a low angle photo it should be present on the model. The tricky bit is reconciling the assembly of the scoop gear with the need to assemble and dismantle the tender chassis for construction and maintenance. There may be a few different ways of doing this, but this is how I worked it out.

    To start with, there are a lot of parts...
    all the parts.jpg

    The instructions are a little foggy, but combined with the decent GA drawing of a 4,000 gal tender in the Wild Swan LMS Locomotive Profiles No.1 The Rebuilt Royal Scots it can all be worked out.

    I turned up a couple of parts for the gear counterbalance weights and soldered them to the etched representation to make things a bit more 3D. The 'gear up' position of the deflector and the scoop were established from the Wild Swan drawing and the components were soldered up solid in that position. I'm sure there are WT'ers who could make the whole linkage work, and DCC it. The long shallow 'S' shaped link between the deflector gear and the scoop gear seems to be slightly too long to allow both to sit in the 'gear up' position. I pinned it at one end and let it sit where it wanted at the other, where it is soldered solid and out of sight. There's a long, cranked link from the main pivot shaft that runs forward to the operating gear at the front of the tender. Since most of it can't be seen, and it has a lot of getting in the way potential around wheels and brake gear, I chose to cut it short where it disappears from view behind the tender outer chassis frames. I'm not sure I got the detail right for that. I now think that the crank arm off the shaft is 'solid' and the end of the linkage rod is forked. I can live with it. I had to sort out the scoop assembly before I could establish the position of the two drop links that you can see waving in empty space. Much fiddling with lengths of wire and brass lacemaker's pins. About 3,000 words worth of photos below. scoop gear assy 1.jpg

    The scoop is supplied as two brass castings. In its retracted position the lower section of the scoop wraps round the outer chassis cross members and would make dismantling difficult, if not impossible. Notwithstanding the fact that the outer chassis cross members are removable, I just couldn't find a way to wriggle them in and out if the scoop assembly was fixed permanently to the inner chassis. Therefore the top of the big casting was drilled and tapped 10BA so it could be screwed in place on the inner chassis. Maybe not worth the effort, but I milled a little material out of the front face of the scoop so it shows some edge rather than a solid, flat face. The bracing rods are not supplied in the kit but are visible. They are easy enough to make from brass wire, a couple of small turned cylinders and some 16BA nuts. The rods terminate at one of the cross members but are not soldered to it, so that the scoop sub-assembly can be removed independently. You can see the scoop castings are soldered together solid in the 'gear up' position. Quite big lumps of brass, and needed the 100W iron to solder efficiently.
    scoop assy.jpg

    Here's how it all goes together. The scoop gear is fixed permanently to the inner chassis, as above. That inner chassis can be dropped into the outer chassis from above, the cross members having been fixed in place beforehand (did they really need to be made removable in the first place I wonder?). The long, vaguely 'Y' shaped, linkage for the deflector that is pivoted on the front cross member is just clipped in place by some short pins soldered to the cross member lugs. Just don't forget to unclip them before separating the inner and outer chassis! With inner and outer chassis fixed together, the scoop sub-assembly can be houdinied into place around the rear cross member and fixed to the inner chassis with the 10BA screw. Pictures...
    scoop gear assy 2.jpg
    scoop gear assy 3.jpg

    The high water mark of the tender assembly looks like this at the moment...
    scoop gear assy 4.jpg

    There's a lot going on in a small space. It's arguably more complex than the loco chassis. I should mention here that there's not much clearance between the bosses on the Slaters wheels and the inside of the outer chassis frames. The distance between inside of frames on the prototype measures 5' -9 1/2 ", or 40.5mm in 7mm scale. On the model it measures between 39.8mm and 40.0mm, so a little undersize, probably down to etch material thickness being slightly over scale. And of course S7 pushes the wheels out where they should be, so the hair shirt of authenticity itches somewhat. The wheels need the bosses facing off a little to provide enough clearance for the wheels to move as the compensation works. I simply mounted them on an axle, held them in a collet on the lathe, and skimmed off 0.51mm from each boss, leaving a wheel width from back of tyre to front of boss of 3.71mm. That leaves the wheel sets at 38.6mm over bosses, which is OK. Not wishing to make life complicated, I reduced the Slaters countersunk screw at the same time. I could have taken more off the boss, but at that point the hex socket in the screw head was getting rather shallow. Pro Tip (eh?) - take a close look at the ends of your wheel screw allen keys. They're often a little undefined and rounded at the ends. Stone or grind them back a little so that the end is flat and perpendicular to the axis of the key, and all the corners are clean and sharp. Make sure the key is fully home in the socket before leaning on the allen key.

    In the end this is what's visible...
    visible scoop.jpg

    It's clear that if you didn't fancy the full scoop gear monty you could leave out a lot of the fiddly internal gubbins. Brake gear next...
     
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  19. richard carr

    richard carr Western Thunderer

    Ian

    I find that for Slaters wheels and axles in S7, the retaining screw is too long and so is the square end of the S7 axle, As they come you cannot fully tighten the wheel on the axle. I usually take 0.5 to 0.75mm off the square ends of the axle and 2mm off the screw . I also thin the screw at the countersunk end. I find this is needed with slaters finescale wheels that have been thinned down and the S7 group wheels.

    Richard
     
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  20. Threadmark: Just checking in...
    Ian_C

    Ian_C Western Thunderer

    I haven't posted anything for a while. I haven't gone away, I'm just struggling with the whole tender chassis + water scoop gear + brake gear assembly. I've just got to the point where I've solved most of the problems (the ones I can see, anyway) and I've discovered that the brake hanger castings are about 1.5mm shorter than they should be. Since the upper pivots are at the right height relative to the axle centres, all the brake linkage and pull rods are 1.5mm higher than they should be. And that explains why some of the parts simply won't assemble. Clearances are small on the prototype, and a missing 1.5mm just can't be worked around. There's nothing for it but to scratch up some proper brake hangers and make up the brake gear again.

    That apart, I hope everybody's well. The world's a very different place from when I last posted at the beginning of March. Work's been a nightmare, and now we're 'furloughed' until 1st May. I ought to be able to find time for those brake hangers then...