RMweb Premium ArthurK Posted June 27, 2012 RMweb Premium Share Posted June 27, 2012 Chimneys are notoriously difficult things to get just right, yet they characterise not just a locomotive but the look of the railway company responsible for their design. Even after the surgery on this Q5 chimney I am still querying whether I have actually got this quite right and, I think, the barrel of the chimney is a fraction of a millimetre (.25 - .5) too slender, though I think the height, the taper and the top is about right. Mike According to the Isinglass drawing, at the narrowest point the chmney on the A6 is 1'4" wide. That is 5.33mm in 4mm scale. Very often even when made exactly to scale chimneys sometimes don't look quite right. It must be something to do with visual perception between the model and the real thing. The chimneys that I have for the J24 and others are 'correct' but look a bit 'chunky' when added to the model! A thickish base (necessary for good casting) doesn't help. ArthurK Link to post Share on other sites More sharing options...
34theletterbetweenB&D Posted June 27, 2012 Share Posted June 27, 2012 ...In fact, at the maximum loss of diameter on the driving wheels (2.5 inches) the whole locomotive would surely ride some one and a quarter inches lower, which, with carrying wheels at their nominal diameter, would close the gap between their rims and the mainframe cut outs or is this assumption just wrong? The reverse should also be true i.e. driving wheels at their nominal diameter, carrying wheels heavily worn. I guess all of this means that the diligent search for 4 mm wheels of exactly the right nominal scale diameter isn't absolutely necessary. I also imagine that this reduction in wheel diameter, especially on smaller wheeled locomotives i.e. 4' 81/2 " could materially affect their tractive effort. as this calculation has the wheel diameter as a factor... ... and then there is bearing crown and journal wear, the steady degradation of springs in service, and progressive reborings of cylinders to take into account too. Very famously when all the factors leading to the locomotive steadily dropping in service were allowed for, Churchward raised the cylinder centres of the 28xx 2.5" above the driven axle centreline to avoid the cylinder casings fouling the moving loading gauge. And then standardised this offset on all his locos... I once read a lament by a loco inspector concerning an A1 during WWII. It was well worn, but the combination of near minimum diameter tyres and maximally bored out cylinders meant that when the combination of poor coal with insufficient firebar and boiler washout attention resulted in low pressure, the old girl still had plenty of grunt. Returned to nominally new condition after a works overhaul, she wasn't nearly as good when lack of regular running shed maintenance put her in 'neglected' condition once again. As for other nominal dimensions, I was assured by a man who was apprenticed at Inchicore, spent time at Derby and eventually went on to work in aerospace that the standard error in UK practise steam loco frame components, boiler barrels, and the like was around 0.08%. What that means is that if you could take a class of which decent numbers were erected, Black5, 8F, WD 2-8-0, and measured the lot for length, you should turn up a range in length of about 2 inches. So don't be making those P4 models too accurate... Link to post Share on other sites More sharing options...
N15class Posted June 27, 2012 Share Posted June 27, 2012 According to the Isinglass drawing, at the narrowest point the chmney on the A6 is 1'4" wide. That is 5.33mm in 4mm scale. Very often even when made exactly to scale chimneys sometimes don't look quite right. It must be something to do with visual perception between the model and the real thing. The chimneys that I have for the J24 and others are 'correct' but look a bit 'chunky' when added to the model! A thickish base (necessary for good casting) doesn't help. ArthurK Guy Williams prefered to make a chimney that looked right rather than one dimentionally right for this reason. Link to post Share on other sites More sharing options...
mikemeg Posted June 27, 2012 Author Share Posted June 27, 2012 ... and then there is bearing crown and journal wear, the steady degradation of springs in service, and progressive reborings of cylinders to take into account too. Very famously when all the factors leading to the locomotive steadily dropping in service were allowed for, Churchward raised the cylinder centres of the 28xx 2.5" above the driven axle centreline to avoid the cylinder casings fouling the moving loading gauge. And then standardised this offset on all his locos... I once read a lament by a loco inspector concerning an A1 during WWII. It was well worn, but the combination of near minimum diameter tyres and maximally bored out cylinders meant that when the combination of poor coal with insufficient firebar and boiler washout attention resulted in low pressure, the old girl still had plenty of grunt. Returned to nominally new condition after a works overhaul, she wasn't nearly as good when lack of regular running shed maintenance put her in 'neglected' condition once again. As for other nominal dimensions, I was assured by a man who was apprenticed at Inchicore, spent time at Derby and eventually went on to work in aerospace that the standard error in UK practise steam loco frame components, boiler barrels, and the like was around 0.08%. What that means is that if you could take a class of which decent numbers were erected, Black5, 8F, WD 2-8-0, and measured the lot for length, you should turn up a range in length of about 2 inches. So don't be making those P4 models too accurate... I've highlighted your last sentence because it seems to me to sum it up. And, rest assured, there's no danger of me making them too accurately! Regards Mike Link to post Share on other sites More sharing options...
mikemeg Posted June 28, 2012 Author Share Posted June 28, 2012 So after fitting the remaining boiler details and drilling the holes out for the handrail stanchions, the smokebox and boiler assembly has now been fixed to the footplate and to the cab front. I've also fitted the front mainframes and valve cover. The operating rod, on top of the boiler has been fitted and a start made on the handrails. The 'free standing' handrail is just my way of ensuring that these stanchions are both orientated properly and are straight, especially as they are of differing lengths due to the differences in smokebox and boiler diameter. Just a few more things to add and a set of rear footsteps to make and this is about there. And that chimney; well now I'm satisfied that it's right! You can, perhaps, now appreciate how well Arthur has captured the 'essence' of these lovely tank locomotives. Clean lined, simple design but oh so elegant; just the epitome of Edwardian locomotive design! It is, for me, a real privilege to be able to contribute, in some small way, to the development of this range of locomotive kits - thanks Arthur. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted June 28, 2012 Author Share Posted June 28, 2012 And, if anyone's interested, I can now open the other box, which Arthur sent me a few weeks ago, and build an ex-NER Tenant class 2-4-0. Something very different for me, built as these were way back in the 1880's. I'll start a new thread for this one, probably called Building a Tenant 2-4-0 - trial build of Arthur kimber's kit (how imaginative is that - don't say). I will continue this thread until these two A6's are fully completed and painted. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted June 29, 2012 Author Share Posted June 29, 2012 The 'point and click' digital camera, which I have used on the last few photos, even though much newer and with far more pixels, is nowhere near as good as the old one. With the old one, I managed to run my captain's chair castor over the USB lead, which didn't do it any good, hence my using the newer camera. Maplins, they of the electronic supplies (no endorsement here) had a replacement USB cable for the old camera so one was purchased. I also popped into 'The Range' and bought a large sheet of blue paper to use as a background - one or two use this colour and it works well. Those brass tank filler castings, now fitted to the brass body, are really lovely and they make a big difference to the look of the model. Anyone building ex-NER tank locos, whether using Arthur's kits or not, should take advantage of these castings. So by way of a test of the old camera with its new USB cable and this coloured paper, here's a photo of both A6 bodies - the one scratch built, the other kit built from Arthur's kit. Not much to do on either now. Those two bodies are actually the same length, but appear different in the photo. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted July 4, 2012 Author Share Posted July 4, 2012 While doing some soldering work on the Tennant (covered on another thread in this section) it seemed convenient to just 'sweep up' some of the remaining jobs on these A6's. One thing I do need to do is build another front bogie; the two locos are sharing one at the moment. The basis for the A6 bogie, supplied by Arthur, is a set of etchings which he did for the D20 and which produces a fully compensated bogie using side beams on a central 'chassis'. The A6's had a very much simpler bogie arrangement - at least they had once the LNER had removed some of the NER's design excesses bogie brakes, etc. - using coil springs. So the model bogie for the A6 uses this central 'chassis', which has elongated holes already etched into the side members, with built up individual axleboxes, again with some elongation of the axle bearing holes. As already mentioned, the whole bogie frame is sprung allowing the individual wheels to find their level by virtue of these elongated axle bearing holes. I still have to add the reinforcing bars and front frame, linking the bogie frames, and then build up the axleboxes to their final thickness. Now back to the Tennant. Cheers Mike Link to post Share on other sites More sharing options...
MarkC Posted August 14, 2012 Share Posted August 14, 2012 This is a lovely project; I've been following it with great interest. Well done, Mike and Arthur Mark Link to post Share on other sites More sharing options...
mikemeg Posted August 14, 2012 Author Share Posted August 14, 2012 This is a lovely project; I've been following it with great interest. Well done, Mike and Arthur Mark All I can say to your comment, is thank you. I'm enjoying this project though it is stalled, a little, while I finish the Tennant, but once that's done then I can complete the two A6's and the J73. Arthur's kits do capture the elegant simplicity of these North Eastern locos, so very well, and they are a joy to build. Again, many thanks for the comments. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted August 30, 2012 Author Share Posted August 30, 2012 I scratch built the body of the first of these two A6's over four years ago and then laid it aside to await a scratch built chassis. In the intervening time Arthur developed his kit for the A6, so while trial building that I used a second of his chassis' to build for this one. So, after more than four years, this is finally on the road to completion, having now been primed - the trial kit build is just behind it in terms of completion. I've always thought that the 4-6-2 version of these locomotives - the A6's - were just about as 'right' as tank engines ever got, but then I would! I leave it to you to judge. Cheers Mike Link to post Share on other sites More sharing options...
RMweb Gold Worsdell forever Posted August 30, 2012 RMweb Gold Share Posted August 30, 2012 Yep, balanced, elegant and powerful. Coal guzzler, but then nobody's perfect... Link to post Share on other sites More sharing options...
iak Posted August 30, 2012 Share Posted August 30, 2012 Cock on Mike!!! Link to post Share on other sites More sharing options...
micklner Posted August 30, 2012 Share Posted August 30, 2012 Cock on Mike!!! ???????????? Link to post Share on other sites More sharing options...
iak Posted August 30, 2012 Share Posted August 30, 2012 Translation: What a truly delightful, wonderful piece of work ... Link to post Share on other sites More sharing options...
Guest Tom F Posted August 30, 2012 Share Posted August 30, 2012 Absolutely beautiful Mike. Really stunning! Shame it can't run on Leaman Road! Link to post Share on other sites More sharing options...
micklner Posted August 30, 2012 Share Posted August 30, 2012 IAK Much better !! could be taken for something else down sarf !! Link to post Share on other sites More sharing options...
MarkC Posted August 30, 2012 Share Posted August 30, 2012 Nice job, Mike They definitely have a 'presence', don't they? Mark Link to post Share on other sites More sharing options...
mikemeg Posted August 30, 2012 Author Share Posted August 30, 2012 Many thanks to those who have commented on the completed model of the A6 (just needs its paint job). I don't know how far away Arthur is from releasing this and the Class W - the 4-6-0 version - but, hopefully, those of you who model the NER, LNER or BR (NE), in its early days, might like to build one, or two, or .... As Mark C observed, these locos had a certain 'presence' and there were only ever ten of them. This model will actually be 69796, which had a major overhaul and repaint in June 1950. My layout is set in June 1950, so this is going to be in ex-works condition; literally the day it came back from Darlington. And, Tom F, these were very definitely 'in bounds' for Leaman Road in 1950; Starbeck had more than one. Cheers Mike Link to post Share on other sites More sharing options...
RMweb Premium ArthurK Posted August 30, 2012 RMweb Premium Share Posted August 30, 2012 Many thanks to those who have commented on the almost complete (you can see the holes in the mainframes where the guard irons will fit) model of the A6. I don't know how far away Arthur is from releasing this and the Class W - the 4-6-0 version - but, hopefully, those of you who model the NER, LNER or BR (NE), in its early days, might like to build one, or two, or .... Mike Only a few little castings are required to complete this kit. Additional backhead fittings including the drivers Dreadnought brake valve, the Westinghouse brake valve and train heating control. I hope to get these ready for November. The final check on the etches should be with me next week. These will incorporate minor changes to overcome problems that Mike and myself have found. ArthurK Link to post Share on other sites More sharing options...
mikemeg Posted September 1, 2012 Author Share Posted September 1, 2012 So, having got the scratch built A6 body now completed, apart from the paint job, let's turn the attention to Arthur's A6 kit. One of the things he sent me, quite recently, was a very nice white metal casting for the bunker breather. This was a pipe with a breather on top, which sat up against the inside rear of the bunker. Now this casting has to be positioned centrally against the inside of the bunker rear, it also needs to protrude some 4 mm above the top of the coal rails; this according to the Isinglass drawing. As it's white metal, then soldering it could damage it. Supergluing it would work but what if the positioning is very slightly adrift, this stuff goes off very quickly? So I need to be able to adjust the position of this component before I fit it - contradiction in terms, surely? The answer was to cut a former which would fit up against the inside of the bunker and lie flush with the bunker rear so recesses were cut where handrail knobs protruded into the bunker. The breather can then be cut to size and checked against the bunker rear - in my case I cut 4 mm too much off of it, though I did this deliberately because I wanted 10 mm of the white metal 'pipe' for another purpose. So the centre line of the bunker can be drawn on the plasticard former and the level at which this white metal component needs to be fitted can also be drawn. Then a blob of Araldite, locate this breather and just leave it. Now it fits into the bunker with the breather exactly central and at the right height. Cheers Mike Link to post Share on other sites More sharing options...
Paul Cram Posted September 1, 2012 Share Posted September 1, 2012 I use loctite 638 for securing details like this where some adjustment is required as it doesn't go off too quickly. It is very stong afterwards though. Link to post Share on other sites More sharing options...
mikemeg Posted September 1, 2012 Author Share Posted September 1, 2012 I use loctite 638 for securing details like this where some adjustment is required as it doesn't go off too quickly. It is very stong afterwards though. Thanks for the tip, Paul. I guess with loctite 638 I might have time for a quick sip of me coffee, while it's going off; with Araldite I've probably got time to pop over to Columbia and collect the coffee beans. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted September 5, 2012 Author Share Posted September 5, 2012 Looking at the photo of the A6 model above - the one in grey primer - the loco looks much more 'modern' than the loco shown below. Yet they were the same class and had only a few visible differences; the smokebox is shorter on the saturated locos (as below), the chimney and dome, on the one below, are original to the rebuilds and the sandboxes were different. That's about it for the differences yet this version probably shows its Edwardian ancestry far more than the one above. I still have to add the boiler/smokebox and cab door handrails, front lamp irons, works plates (which were mounted on the sandboxes), vacuum pipe from smokebox to cab and the brake and train heating pipes. The buffers on these locos were a mixture of LNER group standard on some locos, NER round on some locos and NER oval on others; this one had NER oval buffers. Then a coat of primer and both locos will be painted simultaneaously - 69796 above and 69798 below. Who knows, I might yet build even more of these lovely tank locomotives. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted September 5, 2012 Author Share Posted September 5, 2012 Do you ever take a photograph of a model and then blithely whack it up onto RMWeb on automatic pilot; this at some unearthly hour in the morning? Then, still in a state of semi-conciousness, you log out and stagger off for a cup of coffee, intent on coming back to it a few hours later, when full conciousness has returned? Well I did, and when I looked at the photograph above, that operating rod just shouted 'Hey, I'm not straight'. And it isn't straight. Reason is one long handrail knob and one medium handrail knob holding that rod in place. So, quick fix, quick replacment and now that rod is straight. Cheers Mike Link to post Share on other sites More sharing options...
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