Ravenser

Here , I'm afraid, we diverge on philosophical grounds. To each wheelset , there is a matching track standard. To each track standard a matching wheelset. The idea of the "one size fits all wheel profiles" track standard is a snare and a delusion from which the hobby in Britain would be better if it could free itself. To be blunt , I don't care whether some US ready to run HO (I suspect a few specialist items) is fitting wheels too fine to fit NMRA S3 track properly. I don't model US outline, or in HO and policing their standards to stop someone causing the mayhem Slaters have unleashed in 7mm is not my concern (Is it 5 different track gauges we now have in 7mm scale or 6 , as a result of people trying to adjust the track to suit a non-standard product?) A wheel standard is what it says it is - a standard - and one thing that OO modellers really do need to do is prevent a reemergance of significantly different wheelsets from different manufacturers . Those active in the gauge do not want it . There are no OO RTR models with RP25/88 wheels , and I hope we never see any. This is an engineering issue , where consistancy and compatibility are paramount. Different and divergent wheelsets are a problem to be eliminated. We already have a divergence with Heljan using 14.2mm B2B on RP25/110 wheelsets. I wish they would get in line and use 14.4mm like everyone else , but the practical reality is that one RTR manufacturer's current production will not run through OO-SF without adjusting the B2Bs . And since they have a Beyer-Garrett and an LNER 2-8-0 imminent this is no longer an issue that can be swept under the carpet as "just a problem for modern image modellers who aren't a majority of the hobby so we can ignore it." I personally don't have a problem with the idea of tweaking B2Bs, and no second hand trader ever checks the B2B of what he sells so it makes no difference to the resale value. But again the practical reality is that a significant proportion of the hobby will never adjust wheels - to be honest a significant proportion of the hobby doesn't know what a B2B is, never mind what value it should be or how to adjust the wheelset or source a B2B gauge. So anyone making OO track is saddled with accommodating Heljan's current RTR as it comes out of the factory, otherwise he will get people complaining to him that his new points "don't work and are no good". For the record, as a factual point, the flangeway for DOGA OO Intermediate is 1.2mm , not 1.3mm , if expressed to one decimal place (which implies a possible error through rounding of 0.05mm +/-), or 1.20mm subject to a published tolerance of +/-0.05mm The actual datasheet is here, if anyone wants to verify : http://www.doubleogauge.com/standards/commercialtrack.htm (I understand that the actual calculation is that a flangeway between 1.27mm and 1.15mm will fit accurate RP25/110 wheels.) Given the Heljan situation, any manufacturer of OO points will need to be near the top end of that range - at which point backward compatibility with quite a lot of 20th Century RTR is there for the taking. Compatibility with a significant body of existing older models - many of them good enough still to be in production under new owners - is going to be much more important commercially than compability with hypothetical models which someone one day might make to a finer wheel standard than any RTR manufacturer in Britain has ever considered As far as "what production run are we tooling for" - it should be quite sizeable , over time. Using some plausible assumptions for a "quick and dirty" calculation, let's say that the "average" OO layout has 20 points. That's an average between a small branchline terminus and a big continuous circuit layout. Let's say the hobby is 100,000 people - that is an estimate based on magazine circulations, (so it excludes the trainset market, which won't be buying this product) and I reckon is pretty close . A second, rather more speculative assumption is that 50% of those are in OO, (so 50,000) with O, N, P4/EM, OO9 and everything else making up 50% We will now assume that those 50,000 modellers , on average each build one layout every 10 years. That instinctively feels a bit low - but then we have to consider those who don't build layouts, and those building lots of layouts are probably building small ones. So that gives us 5,000 OO layouts being built each year , with an average of 20 points per layout - or a market for OO points of 100,000 units per annum in Britain Assume you are going for 25% of that market , and will have 5 items in the range . That is 25,000 units , divided by 5 products , or 5,000 of each item each year. If the tooling lasts 10 years, that's 50,000 units, or 100,000 units over 20 years . That sounds plausible, and rules out Heljan-style soft tooling good only for a few thousand units . (At this point it strikes me the current economic environment may actually be quite favourable for this venture , because with interest rates so low the discounted-cashflow figures on this kind of steady longterm product must look better than in the past)

The DOGA Intermediate standard means rather finer check and wing rails than current Peco (which are 1.39mm flangeways from memory) , and as a point of fact most handbuilt OO pointwork out there is already compliant with the Intermediate standard (since the old BRMSB standard falls within it's tolerances). With modern RTR wheels being to RP25/110 , drop-in should not occur (OO-SF seems to have been a 1970s response to drop-in with Romford wheels on kit-built steam locos). Another practical point is that Heljan , (plus Airfix, Mainline and Replica stock) will run through pointwork to DOGA OO Intermediate standard , but will require adjustment of the back to back in order to run through "OO-SF". Any new OO points to a standard not compatible with all current production RTR face an uphill battle - and now Heljan have started making steam engines, this is no longer "just a modern image problem". It's a potential issue for everyone. Furthermore RTR flanges are arguably a bit thick to be absolutely ideal to run through the narrow EM flangeway To be honest for me consistancy between wheels and track and the improved running that results is rather more important than the absolute thinness of flangeways and wheel tyres - especially as moving to Intermediate would mean an appreciable reduction in the flangeway anyway

A quick comment on loose heeled switches versus flexible rail switches and a few other detailed points.... As I mentioned earlier , my little Blacklade layout (see the blog) is laid with Marcway points and SMP flexible track. The 4mm scale sleepering is a vast improvement over Peco's efforts - any complaints about blobs of solder instead of chairs are slight , compared to the benefit of the improved sleepering. (I know that fully chaired track looks better but it's very fiddly to make and much more fragile) As only a few points are involved, I could stand the expense of buying Marcway . But Marcway could never cope with demand if everyone tried to buy from them . (Think Ultrascale waiting list, cubed...) However I have to differ from Hayfield in thinking they've gone the wrong way about the switch rails. I use DCC , and I had to regap the sleepers and add electrical bonding before laying, as well as cutting through the switch rails to isolate the frog electrically. If Marcway had just built them as is standard practice for handbuilt copper clad - isolation gap down the middle, between switch rails, copper clad continuous between switch rail and adjacent stock rail, frog ready isolated for switching by the point motor - all that work would have been unnecessary Secondly and much more seriously, flexible rail switches at Marcway's 36" radius are horribly stiff. The bespoke single slip in the footprint of a Peco slip is even more so - the switches are really very shortThe major problem in terms of reliability on the layout has been points that haven't closed fully because the "flexible" switches are so stiff that the drive wire from the Tortoise bends instead of throwing the point fully (or even at all) . I've had to replace the supplied wires on nearly all of them with thicker steel wire that has left nasty bits in the cutting edges of my Xurons, I've spent days excavating round the tie bars with scapel and tweezers to ensure the damn things throw fully , and even now there's one crossover - unfortunately forming one end of the runround loop - which will derail a Hornby 31 about 50% of the time when set for the crossover . Other things (DMUs) are less sensitive to it, but I'm still going to have to detail up an old Airfix 31 to have a suitable loco for any train that needs a run round move (The Hornby 31 will then be cascaded to serve as the second loco needed for working a loco-hauled substitute, Minories style). The slip , despite having a Colbalt Blue under one end , which seems more effective (supplied with a thicker wire, and as it's smaller the wire is shorter , which I believe reduces the flexibility) still causes me to hold my breath occasionally and carry out a visual check when it throws Given that many OO modellers will require points tighter than Marcway's 36" radius minimum , and would face even bigger problems, I am strongly against "flexible" switches being used on any RTR product.

The next substantive , which hasn't been raised, is "track standard". My big fear when I read Martin Wynne's heavy hints about a possible product from south of the Equator relates to this. Certain very vocal voices from south of the Equator have routinely disrupted discussions like this over the last 7-8 years. One of their tactics - especially in a notorious poll - has been to present only 2 options : either Peco "as is", or "a new OO track to a track standard too fine to take any current RTR wheels" My fear is that a south of the Equator track source might have been influenced/mislead by those very vocal voices south of the Equator into producing a preoduct which won't be compatible with current British OO RTR and which will therefore fail. That would be a disaster for us all. A new OO point should be made to a "standard" fully compatible with modern RTR wheels (RP25/110) - current Peco is too coarse to be ideal. As a DOGA member I believe DOGA's OO Intermediate Standard fits the bill - and the old BRMSB track standard, widely used by those building therir own OO track, is (just) compliant with the DOGA Intermediate standard. For me , this is the way to go

Turning to the substantives: The first , perhaps , is geometry. Joseph Pestell's opening post says : I think there is a lot in this. However , I would question why we should depart from the Peco Streamline geometry which is the de facto standard in RTR OO , and which nobody seems unhappy with. I know it won't reproduce the flowing bespoke looks of complex formations on the real thing - but no RTR track range can do that, and if there are only going to be afew items in the range , the "decent OO track " range being proposed won't do that either This goes directly to the question raised by Joseph of the proposed track centres. I don't think a commercial ready made range can change from Streamline's current 50mm centres. If you go to a "scale" 45mm, then Mk1s will foul each other on a double track curve at less than 2'6" . With C3 restriction stock at the 72'/23m mark you'll need rather more than that. The practical reality is that a lot of folk are in OO because the only way they can build their layout in the space they have is with curves down to 2' or below. And a lot of folk will now be running C3 restriction stock . So 50mm centres are the tightest that's practical for the OO market. I say this even though both my little home layout and the club project I used to be involved with used 45mm centres. In the case of Blacklade, it's terminus to FY, effectively straight and the min radius is 2'6" , and I was very restricted in width Joseph refers to "no 6" points , but does this mean the C+L style prototype B6, a US geometry "#6" or a Peco medium point? I'm not sure there's any obvious benefit in switching to the different geometry of the first or second - and it goes against reusing the geometry and rail components of existing track

While I'm sympathetic to encouraging people to have a go at building their own pointwork , we have to accept the fact that only a limited proportion of the hobby are able to build their own pointwork and achieve an acceptable result. Nothing is ever going to drive that proportion above 10-20% of the hobby. I am confident that even in the 1950s 3/4rs of the hobby used ready made points (I suspect the truth is that the other 25% called themselves "scale modellers" and didn't believe the great unwashed of "proprietory modellers" were really part of railway modelling as they understood it - but I would respectfully suggest that that caste distinction should have been buried at a crossroads with a stake through its heart several decades ago). Furthermore the work and time involved mean that almost everyone who builds their own pointwork is limited to building a small layout. Martin, having been heavily committed to the trackwork on Adavoyle , will probably have a far better grasp than almost anyone of the implications of trying to build a big layout using handbuilt track. Handbuilt pointwork is nice, and to be encouraged, but any approach that de facto excludes 80% of the hobby - and virtually anyone who wants a big layout - from ever enjoying the benefits of better track is not going to solve this issue. Put very simply, almost anyone who wants a big layout is going to build it in OO and perforce will use ready made pointwork. So ready made OO pointwork is needed - suggesng we should stop asking and just build our own is like those postings suggesting that we shouldn't want new RTR models and should just build a loco kit instead

What's wrong with "post-privatisation"?

I suspect the problem may have been the phrase "steam age diesel" , which does look odd and to me suggests something more like a County Donegal railcar or the Ivatt Co-Co, not the 1960s.. I can't help wondering if "1960s ER diesel depot" would have made it through unchanged

What about electric layouts? Shildon-Newport anyone? Tyneside electrics (someone needs to build and use those nice Judith Edge etched kits for EB1 and EF1)

I don't think you can have a plan for what other people say. You are free not to use a term if you don't like it, and to use something else. That's your personal choice . But others are free to use the terms they wish. It strikes me this thread is not about what terms those posting use but is intended as a message to others as to what you think those others should say, or be allowed to say..... " Post-privatisation seems a conveniently clear and precise term for the post BR era , and it seems to have a pretty wide currency . It would be fair comment to say that "modern image" is associated with BR - it referred to the Corporate Image launched in the mid 60s - and therefore models of the privatised railway are not "modern image"

It isn't listed in Forsythe's book , and I have a clear recollection of hearing Pete Waterman say that he produced a 4mm whitemetal kit for the Dean Single in his days as M&L Kits (c1980?) . I suspect this is the kit you were thinking of - it's not normal for kit producers to issue something that's already available as a kit in a similar material

The last government discovered - or thought it had discovered - that building a media narrative was an entirely adequete substitute for building things, and involved much less hassle . I will believe they intend to build it when I see construction actually taking place

2380 at Worcester being a case in point - the top of the boiler is matt not gloss - is that soot? Some fascinating and remarkably early material

I suspect that what they are actually going to do is send smoke signals to one side that they're going to pull the plug on the project, and give off the record briefings from anoymous sources to friendly journalists indicating that actually they're really supporting it to please the other side. All these things are entirely deniable after the event, ("Ah but I never said that - it was just some journalist's story") which is the whole object. If the present Government put up a bill, they will vote against it , to cause political damage while deploying more briefings to signal that actually they'd build the thing if they got into power (thus signalling "We won't let the Tories build HS2 so if you want it you've got to put us in office") I wouldn't expect them to take any position which couldn't be denied on the subject till they publish their election manifesto If elected at the next election, they will then spend the next 5 years giving the green light to HS2 without anything actually happening on the ground , thus keeping both sides of the argument happy We've been here before - nuclear power stations, aircraft carriers, Thameslink 2000, Crossrail, Heathrow 3rd runway etc etc

If they do locally (it's not a huge branch), and I can find a decent match for Brunswick Green, I could be back in business. Thanks for the tip

There's a local car bits shop that does. But I know from looking in the past that he has Humbrol enamels and Revell enamels and acrylicsa and that's your lots - unless I were to go down the cellulose route - which I can't

I'm feeling annoyed. As mentioned I've started work on a Baby Deltic - a Silver Fox kit I picked up cheap secondhand at a show in January. It really should have been a "quick win": just paint the body, hack and assemble some RTR components I already have and there we are - a new Type 2. I want it in 2 tone green (as it will spend most of it's time working with steam stock) and it will become D5901 - which became an RTC Derby loco, allowing me maximum excuses if it appears on a north Midland layout in the blue period. I primed it with a coat of Tamiya detail primer , and brush painted the light Sherwood green along the lower bodysides. Three coats that took. Then I went to prepaint the warning panels and found that my pre 1985 yellow had dried up. I had plenty of tins of post 85 yellow, but nothing before. Sudden grinding halt to progress while I waited for a show on Saturday where Precision were in attendance. Couple of coats of yellow, then this morning , before my blood test at the hospital , I dug out the spray can of Railmatch Brunswick green . I masked up the loco laboriously , I shook the can (perhaps not long enough - it's supposed to have 2 mins agitation) I sprayed, or tried to. At first nothing came out , then I inverted the can and it sprayed. The result was a loco drenched in thick paint with blotches . I hastily wiped the lot off with thinners and kitchen roll, removed the lower masking and went off to the hospital. When I came back I gave it another go. Remasked lower area, shook the can for over 2 mins , went out to spray. Nothing came out. Well a very little mist. Then the button wouldn't depress - removed it , tried again and the can died with a faint gurgle. (It was an old can, but I'd hoped I'd get more than 2 locos out of it) I have now cleaned it all off with white spirit on kitchen towel and cotton bud. This has taken most of the primer off the sides as well , even though the primer must have been sprayed a fortnight ago. When I removed the masking ,parts of the Sherwood Green lower strip on both sides debonded. And I've chipped a buffer head, which will have to be patched I'm having a minor operation on Friday. I may not be able to drive for a fortnight . The nearest model shop is in the same town as the hospital - but not the same part of it - it's not walkable from the station or the hospital . Couldn't have got a can today - it's their day off. Don't think I can get one when I have my stitches out - I'll be dependent on public transport. I can't phone them and ask them to send me a can - Royal Mail have banned sending paint and spray cans in the post (Go to Jail. Go Directly to Jail. Do not pass Go . Do not collect £200, or a can of Railmatch Brunswick Green) I could walk to Halfords and try to get a spray can of a suitable green. But that would be cellulose, and you can't spray cellulose over enamel (meaning the yellow warning panel and the Sherwood Green band) So instead of being able to finish the Baby Deltic during my convalescence , I'm snookered. Drat. Double Drat. Triple Drat....... I suppose I'll have to finish an NRX and some Midland suburbans and start a 31 instead.

In our case there would have been plenty of movements under the sequence - it wasn't any kind of question of "one train every half hour" , nor was it a rural branchline. With junctions at each end of the station , you needed a sequence to avoid conflicting movements conflicting . But the edict was "You can't use a sequence - just run trains round on a circle". And the whole point of putting in some freight sidings for shunting was to have something going on one corner continuously . But no - "We never shunted on the last layout" It's interesting that the moment a sequence or prototypical operation is mentioned, people assume that it means the layout being motionless and devoid of trains for long periods Personally I'm happy to admire a model of the railway, one element of which is the trains , rather than focusing exclusively on the stock or even the locomotives, so I may be less likely to complain than most about trains that run on less than Central Line headways . Both the club project and my own layout largely revolve/revolved around multiple units , so for the loco-centric they might not have been of interest anyway. But a lot of the network doisn't see many locos these days, and I'd argue it's a blinkered approach simply to ignore such railways - in real or model form - as of no interest to anyone

Jeremy C "Little Johnny wants to see the trains run" . While it is widely assumed (i) that any decent layout will be an exhibition layout (ii) that a crucial element of exhibitions is to recruit children into the hobby and (iii) that the spectators, having paid £4 on the door, "own" the exhibitors, who had better "behave" and jump the correct height when told, prototypical operation will always be two very dirty words In the context of a club project I remember being instructed to remove sidings from a layout plan because "You can't shunt at an exhibition" (evidence at every exhibition notwithstanding), and when it was discovered that we'd developed an operating sequence and were proposing to use something similar in public we were told firmly that we were not allowed to run any kind of sequence in public , and must stick to sending a train out from the fiddle yard for a complete lap of the layout, followed by another train on a similar basis.... Assuming that similar attitudes exist in other clubs , any kind of prototypical operation will continue to be uncommon

This is one of those posts that could go on the layout blog (here http://www.rmweb.co.uk/community/index.php?/blog/343-blacklade-artamon-square/ ) but as it amounts to a note-to-self of stock construction jobs that need doing, it's more logical to put it on my workbench thread . So here it is... I had the layout up for an extended play a couple of weeks back. Things came out of boxes that had spent an awful long time in them . For the first time I actually got round to trying to run a Civil Engineer's train - and found that 2 brakes , a Zander, a Grampus, a Dogfish and a Walrus (all the non-airbraked stuff) were too long for the run-round loop . Pity - they looked rather nice - so the Zander will have to stay in it's boxfile I also found or was reminded that Hornby 31s are a touch track-sensitive, and as the track in question (in several senses) is the crossover at the end of Pl 2 , forming one end of the run-round loop, and as 31 174 has been doing duty on anything that requires running round (the two parcels , the oil and now the CE train) this is a problem . An alternative loco is required for this duty - and a quick trial on the tension-lock fitted Seacows (also never before run in anger) showed that my old Airfix 31 is quite happy taking the crossover even when the blades are 98% across (It's sat modestly hidden at the back). It also runs perfectly well, with inbuilt analogue sound . I already needed another 31 so I could play with a 2 coach loco-hauled substitute set , so detailing up a spare Airfix 31 and fitting Kadees was already high on the "to-do" list. It now becomes an urgent priority It's also painfully obvious that the Hornby Dutch Shark needs weathering, so perhaps I need to finish off the olive green Cambrian kit one, which really ought to be used in a mid 80s CE rake I made the melancholy discovery that my elderly W Yorks 155 may run okay but the wretched black box on the underframe now fouls the newly installed cosmetic point motors on the back road. The 158 just clips them too but keeps going - demonstrated by the appearance of bright metal on the bumps on the casting. A bit of resiting and an emery board and a paint brush has sorted this out as far as the 158 is concerned, but the 155 needs it's chassis sorting out. I have a pack of NNK (ex MTK) underframe castings for a 153..... Fortunately what Dapol tooled up was evidently based very closely on a built up MTK kit, and with a bit of ingenuity it should be possible to use the castings on the powered car for weight, and fret out the plastic on the trailer to build up various boxes without any difference between the cars being obvious . A heavy rework of the W Yorks 155 to make the best of a bad job now rises right up the DMU agenda. On the other hand thoughts of sticking a decoder in the Regional 155 that has never run and has been sat at the bottom of a pile of stock for over a decade have now receded I even got to try running the layout in steam mode for the first time: Now I know this is full of ghastly anachronisms . Nothing can be done about the station signage - that was always a reason why any "steam period" was not going to be a serious exercise, and would simply be a case of giving my out of period items an occasional airing and a raison d'etre But it does show progress and problems,,,, Set 1 (ex LNW) is up and running. Set 3 (Grouping non-gangway) is also up and running , though the coaches need weathering . After I found the Hornby Thomposon non-gangwayed stock is delayed till next year, I thought laterally , and acquired a carmine Gresley CL instead of a maroon Thompson CL Set 2 is still progressing, slowly. But we have a motive power crisis. I have 2 serviceable kettles, and one's an O4/1 and totally unsuitable for suburban passenger working. I have no serviceable green diesels (you can't readily DCC an ex Hornby Dublo Class 20). I ended up using 31 174 and a blue Bachmann 20 just to run trains and check that the coaches ran and a Minories style shuttle could be operated. Really , I need 4 locos to run 2 or 3 trains Someone put a decoder in my secondhand whitemetal N5. I got the 4 digit address programmed then the whole thing started shorting. A check with the multimeter showed a dead short across one pair of driving wheels . It went back in its box pending detailed examination (I suspect it may work fine when the body's removed....) I bought a Fowler 2-6-4T as "secondhand new" at Ally Pally. It needs a decoder hardwiring (when I pluck up courage to get the body off) and more seriously , somehow I have to fit Kadees So I've dug out the resin Silver Fox Baby Deltic kit I bought cheap second-hand at St Albans , and started painting. Then I found my warning yellow had dried up. Now I've got some replacement from Precision at Shenfield (but I dread to think how many coats will be needed - Precision have poor covering power and yellow's a problem at the best of times ) So - finish Set 2 . Two Type 2s to be done (D5901 first - as the RTC Derby loco it only needs a slight stretch to have her survive into the 80s in the Midlands , or indeed to be preserved, then 31 408 ) Finish the NRX conversion . Finish the Cambrian Shark . All of those are existing commitments It becomes a question whether the 128 kit or a heavy upgrade of the W Yorks 155 is next cab off the rank behind that lot. I have no steam age parcels stock . A 51' Gresley full brake (Kirk kit) would be a fairly quick win , and I have 2 old 12T vans with no obvious use which could be done with new chassis and Kadees for parcels tail traffic... That should keep me quiet

A large part of the range has been duplicated either by modern high spec RTR or by etched brass kits . I remember trying to do a count against the listings in Robert Forsythe's book , and I think only something like 30 out of 100 odd kits hadn't been duplicated by a more modern alternative (Eg the Sentinel shunter - of which I built two - has been replaced by the Model Rail RTR commission model) "An absolute catastrophe for the British model railway scene" is a little overstated And I think the moulds for whitemetal are rubber - it might make more sense to buy the masters , if they still exist, and produce new moulds

Without supporting reference I admit I'm a bit sceptical of this . Significantly altering the loading gauge would be a huge operation involving complete rebuilding of every bridge and platform - which is why it's not an option in Britain While I'm not an expert on French railways , the fact is that the SNCF Reseau Nord /former Chemin de Fer Nord are certainly to the same/very similar loading gauge as the rest of the SNCF today. And I've never come across any suggestion that it was ever different , or that there was a huge interwar rebuilding programme to change the loading gauge. More specifically I do have quite a substantial book on the Grande Ceinture and nowhere in that does it suggest that there was any difference in loading gauge between the Nord and the other French companies - since the whole point of the Ceinture was to exchange freight trains between the various lines out of Paris, a significant difference in loading gauge on one , restricting the vehicles it could take , would have been an important operational issue , and I'd expect it to be mentioned . Even more compelling is the fact that for many years the Grande Ceinture was operated by 0-6-2+2-6-0 du Bousquet articulated locos, built from 1910 to an existing Nord design . These things , in the photos, are visibly big, and the width across the side tanks, the height of the cab and the two long tubes mounted on top of a large boiler all look well in excess of anything the British loading gauge could accomodate. But evidently the Nord before World War 1 could take them very happily http://www.aqpl43.dsl.pipex.com/MUSEUM/LOCOLOCO/bousquet/bousquet.htm Finally it seems inherently unlikely that the Nord was built to a significantly smaller loading gauge than other French railways, since as I understand it, all French railways were built by the state , and engineered by the same small pool of government engineers trained in the same Grande Ecole , but then leased to private railway companies to operate. (This certainly applies for the 1840s when the Nord main line - and the PLM and P-O main lines -were built). I'm struggling to see why main lines built at the same time by the same small group of people for the same ultimate boss, as part of a national programme would be to radically different loading gauges. Especially when the French state , with it's tradition of rigid centralised uniformity, was involved.... A programme of modest clearance adjustment in a limited number of tight spots seems possible , but a wholesale rebuilding from something like the British loading gauge to Berne gauge across Northern France doesn't, so I'd be grateful for some specific references. (While obviously quite a large area of Northern France needed reconstruction after WW1, and any loading gauges might have been addressed at the time, the mainline from Gare du Nord to Calais was not in the area of the fighting, except for brief periods around Amiens) In the absence of specifc details to the contrary, I'd still say that the loading gauge from Calais to Paris was always substantially larger than in Britain, although as built it may not have been exactly the same as the current Berne gauge [but we're some way away now from the original enquiry about whether big LNER steam and Bulleid Pacifics could be mixed at any location]

The GC London Extension was certainly built to a "Continental" loading gauge , larger than the British norm , and this is frequently referred to in accounts of the London Extension. This must mean that Watkin was serious about the idea of through Manchester-Paris trains - though whether he had fully thought out the implications across London is another matter The Chemin de fer du Nord was built to a much larger loading gauge than is normally used in Britain - as can be seen any day of the week at Paris Gare du Nord. The Eurostars are significantly smaller than other stock and "standard" TGVs run to Calais, Dunkirk and Boulogne over conventional tracks . Corails and other standard SNCF coaches were used freely on the old conventional Nord mainline without any restriction that I'm aware of

What exactly would have been permitted down the Widened Lines as far as Farringdon? If you assume that the GC operated through trains onto the Southern companies via Baker St /Farringdon, and that you were modelling Ludgate Hill on the basis that it didn't shut in 1929, and that through trains off the GC changed engines there what could be assumed to get down the Widened Lines as far as Ludgate Hill without bending credibility too far? I know N1s went through Snow Hill and I think J50s as well - but were N2s banned on weight grounds - though they certainly worked into Moorgate? Could a Director be got down the Snow Hill route ? Or a Jersey Lilly? (Directors are at least available RTR). A3s were used on the GC in the late 30s but I presume would be an absolute no-no on the Widened Lines , even with a touch of modeller's licence. What about B1? L1? A5?? J11? (B1s are cleared for the W Highland so I think have a fairly good RA ) Ludgate Hill as an LNER/SR interchange station would have some potential - the spam cans could work in from the south, and although an A4 is too much , some kind of LNER main line loco could be possible under such a scenario. The GC London Extension was desperate for traffic so under Sam Fay the GC was active in developing cross country expresses - a couple of main line trains to the South Coast via Snow Hill would be plausible if the connections had existed...

Dreadful thought - presumably it would have been Farringdon , as a joint GC/Met/SER operation...