mikemeg Posted December 21, 2012 Author Share Posted December 21, 2012 While a couple of issues around the motion plate design are resolved, I've assembled the tender superstructure. This is Arthur's standard NER 3940 gallon tender and does make up into a lovely representation of these quite distinctive tenders, with their four coal rails, plated over the coal space. The support for the reversing rod has also been repositioned so that it lies between the two layers of this rod. Cheers Mike Link to post Share on other sites More sharing options...
mikemeg Posted January 1, 2013 Author Share Posted January 1, 2013 Work on the chassis assembly is now proceeding with the brake hangar brackets attached and the leaf and coil springs also attached. The fully equalised front bogie has also been built. This chassis does employ CSB's and both the maths and the subsequent implementation give a standard deflection, on all axles, of around .5 mm with the weighted loco body on. The tender will also be fully CSB fitted using the High Level 2 mm axleboxes, hornguides and CSB tags. Interesting thing about the wheels. The Alan Gibson catalogue lists a B13 wheel, of the correct diameter, but with 20 spokes. Now the B15 wheel (and probably by inference, the B13 wheel) had 18 spokes. The Gibson catalogue also lists an 18 spoke wheel of the correct diameter, intended for the Tilbury 4-4-2 tanks. Even the crank throw is the same. So I opted for the Tilbury Tank wheels and they are much nearer correct (I hope) for this locomotive. As with most ex-NER locomotives of this era, all bogie and tender wheels were 12 spoke, rather than the more normal 10. So now to check out the connecting rods, crossheads and the slidebar assemblies, while I await the High Level gearbox. This photo probably shows why this model won't traverse the very tight curves of some 'OO' layouts, without some modifications to the front mainframes. Link to post Share on other sites More sharing options...
MarkC Posted January 1, 2013 Share Posted January 1, 2013 All very interesting and useful details there about wheels & suspension, Mike. Thanks. As for the question of tight curves, I see what you mean. Obvious solution would be to open up some arches to clear the wheels, of course. Now I don't think that the ones behind the crossheads would be particularly obvious, but the leading wheel ones certainly would. As it stands, what radius curve do you envisage the model being able to cope with? Mark Link to post Share on other sites More sharing options...
mikemeg Posted January 1, 2013 Author Share Posted January 1, 2013 All very interesting and useful details there about wheels & suspension, Mike. Thanks. As for the question of tight curves, I see what you mean. Obvious solution would be to open up some arches to clear the wheels, of course. Now I don't think that the ones behind the crossheads would be particularly obvious, but the leading wheel ones certainly would. As it stands, what radius curve do you envisage the model being able to cope with? Mark Mark, I don't know but I'm guessing that the minimum radius which the model will cope with is probably 3' 6" to 4' 0". The front mainframes could probably be pinched in a little more which would reduce the minimum radius capable of being traversed. As the minimum radius on Hessle Haven (my own layout) is the ruling radius of a B8 turnout, then this isn't a problem for me but I realise that not everyone has that luxury. Cheers Mike Link to post Share on other sites More sharing options...
Horsetan Posted January 1, 2013 Share Posted January 1, 2013 ......Interesting thing about the wheels. The Alan Gibson catalogue lists a B13 wheel, of the correct diameter, but with 20 spokes. Now the B15 wheel (and probably by inference, the B13 wheel) had 18 spokes. The Gibson catalogue also lists an 18 spoke wheel of the correct diameter, intended for the Tilbury 4-4-2 tanks. Even the crank throw is the same.... Slightly OT, but that's not the only oddity in the AGW range. There are two types of 6'2" LNER mixed-traffic driving wheel, intended for B1s, V2s, A2s, etc. However, one type has 20 spokes, whilst the other has 18. All of the prototype photos I've come across (including in RCTS and Yeadons Registers) show 18 spokes; has anyone managed to stumble across an engine with 20-spoke drivers? Link to post Share on other sites More sharing options...
Paul Cram Posted January 1, 2013 Share Posted January 1, 2013 According to my Sharman wheel specifications the Thompson B1 and Peppercorn A1 and A2 had. Link to post Share on other sites More sharing options...
Horsetan Posted January 1, 2013 Share Posted January 1, 2013 According to my Sharman wheel specifications the Thompson B1 and Peppercorn A1 and A2 had. Certainly that's what the book says, but I've not been able to find any photos of any of those classes sporting a 20-spoke wheel; it has always been 18..... Link to post Share on other sites More sharing options...
RMweb Premium ArthurK Posted January 1, 2013 RMweb Premium Share Posted January 1, 2013 All very interesting and useful details there about wheels & suspension, Mike. Thanks. As for the question of tight curves, I see what you mean. Obvious solution would be to open up some arches to clear the wheels, of course. Now I don't think that the ones behind the crossheads would be particularly obvious, but the leading wheel ones certainly would. As it stands, what radius curve do you envisage the model being able to cope with? Mark The prototype model chassis built in P4 (but unpowered) was successfully pushed around a three foot curve. That is the norm that I try to aim for but no doubt the OO modellers would like it to be a little less. Anything less than tnirty inches is pushing things a bit. Frame cutouts for the bogie wheels are possible but it would compromise the appearance of the front end. Even the NER eventually saw the wisdom of using smaller bogie wheels which would pass under frame cutouts. I believe that the V09s (the later C6s) were the first. As an aside the B15 is not as bad as the D20 (NER R). That had four foot bogie wheels which allowing for the tyres had a clearance of less than two inches under the footplate sheet. Admittedly the frames were tapered inwards (as were those of the B15) but not by much. I must confess to using smaller wheels (I think that they were three foot nine inches) on mine. ArthurK Link to post Share on other sites More sharing options...
MarkC Posted January 1, 2013 Share Posted January 1, 2013 Arthur & Mike - many thanks, & a 3' minimum radius would be absolutely fine for most folk who would build one of these lovely models, I would have thought. Agreed, Arthur, putting cutouts in would make it look 'odd' - it's certainly something to be avoided if possible. That's an interesting point about later NER designs too - cutouts as opposed to narrow-spaced frames. Cheers Mark Link to post Share on other sites More sharing options...
RMweb Premium Michael Edge Posted January 2, 2013 RMweb Premium Share Posted January 2, 2013 According to my Sharman wheel specifications the Thompson B1 and Peppercorn A1 and A2 had. There are a lot of errors in the Sharman book, although it's still very useful (and it was the first attempt to put this sort of information together) mine is now littered with notes and amendments. Michael Edge Link to post Share on other sites More sharing options...
Paul Cram Posted January 2, 2013 Share Posted January 2, 2013 There are a lot of errors in the Sharman book, although it's still very useful (and it was the first attempt to put this sort of information together) mine is now littered with notes and amendments. Michael Edge I personally haven't found any and I always cross reference with RCTS and photos for the locos I am building but don't doubt what you say is true. I do not model later than 1940 when the vandal took over so I haven't checked the accuracy of those locos. I also have not looked beyond the LNER and constituents although these days it's mainly NER. Link to post Share on other sites More sharing options...
mikemeg Posted January 2, 2013 Author Share Posted January 2, 2013 Time for a check on the chassis fit under the locomotive body; everything seems to go where it should. I guess this is starting to look like an ex-NER 4-6-0. This photo was taken with only one of the coupling rods on, hence the slight misalignment of that rod; adding the second rod does straighten everything up. Cheers Mike Link to post Share on other sites More sharing options...
micklner Posted January 2, 2013 Share Posted January 2, 2013 Excellent work , well done. Link to post Share on other sites More sharing options...
mikemeg Posted January 11, 2013 Author Share Posted January 11, 2013 Having now received the gearbox, and various other components, I can now continue with the B15, though I have been working on another of Arthur's kits, still under development. The gearbox used on this is the High Level RoadRunner+ 54:1. which has a final drive carriage which can be orientated in different ways and will allow the motor to sit near vertical within the firebox and offset from the driven middle axle. The motor shaft will need to be removed at the top of the motor and the electrical tags will need to be angled downwards to avoid the motor fouling the top of the firebox but it will just go into the firebox. Cheers Mike Link to post Share on other sites More sharing options...
micklner Posted January 11, 2013 Share Posted January 11, 2013 Low gear ratio ? Link to post Share on other sites More sharing options...
mikemeg Posted January 11, 2013 Author Share Posted January 11, 2013 Low gear ratio ? Mick, Yes a low gear ratio but by the time of my model, at the very end of their working lives, these locos were working freights, when they worked at all. So with that working pattern, it probably needs the crawl speed rather than the higher speeds. Cheers Mike Link to post Share on other sites More sharing options...
RMweb Premium ArthurK Posted January 11, 2013 RMweb Premium Share Posted January 11, 2013 Low gear ratio ? I use 54:1 as standard with all my builds. I find that the top speed with a Mashima 1420/1430 adequate for the "fastest" models. I am not aiming at 100mph plus. The smaller wheels on the goods locos scale the speed down nicely - as they did in real life! Even my shunting locos get the 54:1 treatment. ArthurK Link to post Share on other sites More sharing options...
mikemeg Posted January 11, 2013 Author Share Posted January 11, 2013 I use 54:1 as standard with all my builds. I find that the top speed with a Mashima 1420/1430 adequate for the "fastest" models. I am not aiming at 100mph plus. The smaller wheels on the goods locos scale the speed down nicely - as they did in real life! Even my shunting locos get the 54:1 treatment. ArthurK Likewise on most models though I have used the 108:1 gear ratio on some of the shunting locos - J71, J72, J73 - which gives them a real crawl capability but still with enough torque to pull or push a reasonable load at these very low speeds. Yes the top end speed on locos geared at 108:1 isn't very high but it's certainly high enough for these shunting tanks. I first used these very low gearing ratios on a T1 4-8-0 with a Mashima 1630, and that will pull/push upwards of fifty wagons at a crawl. Cheers Mike Link to post Share on other sites More sharing options...
micklner Posted January 11, 2013 Share Posted January 11, 2013 Good info, thank you for the replies. Link to post Share on other sites More sharing options...
Earlswood Nob Posted January 12, 2013 Share Posted January 12, 2013 Morning all I also use 54:1 on freight locos, and 60 or 80:1 for shunters. I also have used 108:1 for a T1 which has superb power/low speed, and Y7&Y8 with Mashima 1015 motor and they will pull/shunt five coaches easily and run smoothly at less than scale walking pace. Who wants an unfitted freight running at 100mph? When I first started model kit building, I visited Alex Bowie's shop in S.London (he must be long gone) and he told me anybody can build a fast loco, but the skill comes in producing a loco that runs smoothly at low speeds. Earlswood Nob Link to post Share on other sites More sharing options...
mikemeg Posted January 12, 2013 Author Share Posted January 12, 2013 Morning all I also use 54:1 on freight locos, and 60 or 80:1 for shunters. I also have used 108:1 for a T1 which has superb power/low speed, and Y7&Y8 with Mashima 1015 motor and they will pull/shunt five coaches easily and run smoothly at less than scale walking pace. Who wants an unfitted freight running at 100mph? When I first started model kit building, I visited Alex Bowie's shop in S.London (he must be long gone) and he told me anybody can build a fast loco, but the skill comes in producing a loco that runs smoothly at low speeds. Earlswood Nob Certainly will go along with this comment. I spend a lot of time trying to get the unpowered, rolling chassis as free running as possible before fixing the final drive gear. Accuracy in the quartering of the wheels, the use of a chassis jig to ensure that the wheel spacing matches the spacing of the journals in the rods and a minimum of slop in the journals all contribute to that. My target, on any model, is that it should be capable of running - light engine - smoothly down to a speed where each wheel revolution is longer than ten seconds. If they'll do that then I know that they will run smoothly throughout their speed range. On shunting movements or unfitted freights moving off, I love to hear each wagon buffering up, or tensioning up on the three link coupling, just as the real things did. I have read, on other threads, that there is no need for locos to be sprung or compensated and no need for the use of chassis jigs and other relatively expensive tools. And, of course, perfectly acceptable models can be made without recourse to any of this. But I find that to make a model which performs as closely as possible to the real thing and which looks as close as possible like the real thing, then there are no short cuts. It takes a little more time, requires a little more care and accuracy and, especially in P4 (and probably EM too), very careful attention to clearances. Arthur does not compromise, very much, on the clearances on the motion design in the pursuit of prototypical accuracy. Building these 'trial builds' with either no instructions or a very minimum of instructions does also help to focus the mind on just how some things can be done and is a great learning experience! So now to strip this chassis back and prime and paint the mainframe assembly prior to final assembly. Cheers Mike Link to post Share on other sites More sharing options...
Mrkirtley800 Posted January 12, 2013 Share Posted January 12, 2013 Mike, I totally agree with what you say. I always use compensation on my tank locos together with a decent motor and gearbox. My tender engines are not all compensated but I fit pick ups on the engine and tender. Strangely the only exception is a NER class P 0-6-0, which picks up only via the tender which is split frame, and is one of the best performers I have. When I ran an exhibition layout this was the most popular engine for doing a quiet spot of shunting with my co-operators, which didn't go down too well as I am a dyed in the wool Midland man. Incidentally they are all to EM gauge. Derek Link to post Share on other sites More sharing options...
DougN Posted January 23, 2013 Share Posted January 23, 2013 Mike and Arthur I am extremely interested in what you have written regarding the gearbox ratio. I will have to try the 1:54 in my next build (J26 or J27 Bradwell) Having built thefrom Q6 with I think a 1:54 it has a decent turn of speed. The Black Hawthorn from High level with teh 108:1 is seriously slow. One day Arthur I must get some of your kits! Link to post Share on other sites More sharing options...
45609 Posted January 23, 2013 Share Posted January 23, 2013 Doug, Sorry to be pedantic but my mathematical mind went into overdrive for a minute when you said a 1:54 ratio on a Q6. I presume you mean 54:1? However, if you indulge me for a moment and think about 1:54 ratio (if it were possible) on a model loco with 18.5mm wheel diameter. The top speed (lets assume you'd use a Mashima 1420 motor) would be in the region of 940 metres per second. At motor maximum power output of 9000 rpm, for optimum haulage capacity, the speed would be a more modest 470 m/s! I guess the design office of the NER never really thought about supersonic capability and high Mach number effects on the Q6. Mike, Apologies for my flippant interjection. I've been following the B15 build avidly and it is all very interesting. Cheers.....Morgan <tongue firmly in cheek> Link to post Share on other sites More sharing options...
jwealleans Posted January 23, 2013 Share Posted January 23, 2013 940 m/s..... is that really 2,103 mph? Would it need that windjabber at that speed? Amy theories as to the minimum radius curve you'd require? Link to post Share on other sites More sharing options...
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