Denbridge

Possible construction for a simple lower level:

 

JP OO 1.png

 

The idea would be to find a place, or create a place, on the main level where the tracks move away from the edge of the board and inset your underground cutting in that location, as part of the station complex.

 

The open framework supporting the lower level allows you reach the lower level tracks (with difficulty) and the underside of the main level.

 

Keep the lower level very simple - little more than a single or double track circuit with any pointwork as near the front as possible for easy access. Probably no track connected to the main level at all.

Another point to consider. Where is the underground stock for the proposed era going to come from? this would only be achievable through Kit and scratch building. Even a very simple plan as suggested would require a minimum of 2 trains. Is there the skill set/will to build these. And James original plan will require 20 or more sets. 

Thank you all for your replies: that is helpful. The more that I read (both on the forums and elsewhere), the more that I think that quite a bit of testing is going to be very helpful before I start building things. I wonder the extent to which, if at all, I can sensibly start testing things, before the shed is complete?

 

I attach a slightly revised version of the plans, with the lower level fiddle yards reorganised to take up less space (to allow more room for the end of a workbench to sail underneath them), and with both sets of fiddle yards colour coded and labelled.

 

Mike - the floor will be insulated: that is part of the package. In relation to operators, I was not specifically planning on having multiple people operate the layout at once (as stated, I am very interested in computer control - but will have to test what this is capable of doing either with some testing infrastructure that is never intended to be turned into a permanent layout, or with the smaller N gauge layout before committing to a project that requires this in order to work well). It would be good to have the option to have one or two additional operators, and I think that there should be space for a few people in the shed with a layout to this plan: the middle part of the well (not including the tight squeeze at the end) is 4.5m long and between 0.75m and 1.1m wide.

 

In relation to different people having different skills and doing things at different rates - this is one of the main reasons that I am wary of vague advice about "complexity" (especially as regards electronics/logic/programming, where I do have quite a number of years of experience, albeit in a slightly different context), and why I do not think it rational immediately to abandon this idea entirely on the basis of that vague advice without trying a smaller layout and various tests first. (It is really very, very odd that people appear to be hostile for the sole reason that I have not publicly committed to abandoning building a layout along these lines immediately that such a thing be suggested, but have instead stated that I will build a smaller layout and carry out some tests first, and in the meantime revise these plans based on specific feedback received so far and seek further specific feedback on the plans as revised).

 

As to the Nelevator - that is intriguing: I had no idea that those things existed. I am not sure that this will actually be simpler to use than a helix, however; does anyone here have experience of using one? I note the point that the trains would then need turning, and I imagine that a Nelevator plus a whole train turntable (do these exist? How much space would they take?) would probably be quite a lot more complex than a helix, which is quite a well known railway modelling standard by now (although they were unheard of 25 years ago, from what I recall).

 

As to track laying, as stated before, I plan to have the baseboards built professionally, so hopefully I will not need to worry about the flatness of the surface (at least, so far as the baseboard is concerned) to which the track is applied. In respect of the underlay, the convention I know is to use cork, although there are other products (are these worthwhile, or is it not worth the extra money for, e.g., the DCC concepts trackbed?). Obviously, this will have to be cut to the right size with a sharp knife following measurement, laid out in draft with the track resting lightly on it, then glued to the baseboard before the track be finally fitted on top of it using the conventional pinning method (perhaps with the addition of glue; or do people recommend using glue instead of pins?). Is there anything that I am missing here, especially about ensuring the flatness of the cork? I was planning on using the 1:1 printout from SCARM (if I use Peco track at least) to align the track in exactly the right position. I realise that this will require quite a bit of paper and toner.

 

I do think that reliability is likely to be very important, and have spent some time researching things significant to reliability. Recommendations that I have found so far include using electrofrog points (or possibly the new unifrog points if I end up using Peco bullhead rail), increasing the weight of both locomotives and rolling stock, using the PowerBase on difficult sections, installing "stay alive" capacitors in the locomotives if they prove to be prone to stalling, using high quality DCC decoders (i.e., buying "DCC ready" rather than "DCC fitted" and fitting my own decoders), keeping the track clean (I believe that there are special track cleaning tanker wagons), wiring the layout using power districts so that a short circuit in one area does not affect the whole layout, using as large a radius set of curves as can be fit in the space and not having gradients too steep. I suspect that using mostly more modern locomotives is also likely to be helpful (especially if I am using code 75 track). I should note that, freight shunting not being an interest of mine, the possibility for complexities and derailments from shunting small loose wagons is at least eliminated.

 

In any event, thank you all for your help so far; it is appreciated.

James, the main problems with your design, as I see it are as follows ( lets disregard how much you are trying to cram in).

I curves. Off the shelf steam locos simply will not haul the length of trains you require.

2. The helix simply will not work in the area you have. The gradient, combined with the set track curves will cause the same problems as above.

3. Access. There id far too much track under the high level. A potential disaster area, dealing with derailments and maintenance/repairs.

4. there is a disproportionate amount of hidden track feeding a small viewing area.

If you were to abandon the low level, you could move the whole terminus back towards the wall of your shed. Getting rid of the through roads also removes a double junction. With only a small amount of redrawing, you can increase the radii of the mainline approach to the terminus, using curved and tandem turnouts, making it all flow better.You may still have some issues with the return loop, bottom right, but since this is in the hidden fiddle yard, there is no requirement for trains to operate at the slower speeds of the scenic area. The other point to note is that some of the fiddle yard roads are too short to be of any use, but that is easily overcome. I honestly feel that these changes would give you a workable, achievable layout.

Now, bearing in mind that I find myself back in the planning stage of my 'last big layout,' with neither a man cave nor a track plan to show for it yet, I have pretty much every item of stock needed to operate a good representation of the timetable, without the same stock appearing twice except for its booked return working.  

 

So, while James' plan does on face value appear daunting, he may have already, like me, assembled the rolling stock portfolio required, as a form of stake or investment in the project.  I'm not going to venture a figure, but it would nave four noughts.

The point many have been trying to put across is that the plan simply will not work. Off the shelf steam locomotives simply will not haul the kind of trains envisaged on radii this tight, and that is not even considering the impossible helix. If he was going Modern image with Diesels driving on multiple axles he would be in with a shout. but not with steam. And has been said, the lower level is a disaster waiting to happen through access problems alone. 

While all that is true, we have no idea how wealthy the OP is. (And of course, it's none of our business.)

 

For me, the sums you've mentioned would be not inconsiderable. But I know there are some people who would not even look twice at them, or pause at double those prices, or even ten times those prices.

 

It's also I guess a question of timing. If, as everyone says, this layout will take many years to build, dividing those sums by the number of years makes them look much more "reasonable".

 

And if he's anything like me he's been hoarding stock over the years on a "just in case" basis. While I feel lucky to have bought as much as I could reasonably want when the RTR prices were a fraction of what they are now, the last time I started adding up how much I'd spent over the years I stopped before I'd finished, needing to go and have a lie down.

 

It's clearly a hugely ambitious idea. Good luck to him! I really look forward to reading the thread as it develops.

 

Paul

I think I'd have a coronary if I totalled up how much I've spent on this hobby over 40+ years. HaHa. 

However the main thrust of the various posts isn't to put James off of his ambitious plan, it is to try and convince him that it is effectively unworkable, assuming it ever got built.Off the shelf Steam locomotives, even modified, will simply be unable to pull the kind of trains he wants on radii and gradients he proposes to adopt. I would hate to see him spend so much money on a lame duck.

Of course , we have no actual completion stats , no definition of “ complex” , but I broadly agree , I find money not to be an issue for most people , stock is expensive , layouts are comparatively cheap. You buy a lot of PECO for £1000

 

The big issue is sustaining the interst over a long period , especially as aspects of a big layout can be very tedious

 

Personally I don’t like gradients or hidden track and strive to remove them from any layout design.

I can sort of agree, though a reasonable estimate for this layout would be around 3 1/2 to 4 grand for the trackwork alone. Then add the cost of point motors/servos, wiring etc the price is astronomical and the baseboards haven't been factored in. Then IF it was ever built, the amount of stock required to do it any justice would come into the tens of thousands assuming off the shelf products. Even a 2nd hand 12 coach rake of good quality coaches with a good steam loco, say a castle, would be around 250 quid minimum, and more likely double that. so, just 10 mainline trains eats up somewhere between 2500 and 5000 quid and still nowhere near the requirements of this plan.

I know , the two layer aspect of this design, is in my experience, a huge issue and potentially a show stopper , I operate a friends layout and it’s a three level design in 16 by 12 , it works but the track is very well laid and the hidden sections are two track wide , accessible from both sides and no pointwork. Even that is too much for me. My proposed layout has a single branch line that climbs over the main line in a hidden section and I’m serously considering just having no gradients and a hidden ( though accessible ) diamond to carry the branch through the main line.

I have no wish to be negative. I've tried to offer advice based on hard won experience on many layouts, over more than 40 years, mistakes and all. Tight curves and gradients are a show stopper on any layout with mainline pretensions. Access is another. Plus, probably 90% of complicated layouts attempted by solo builders never get finished, usually by virtue of the amount of work, realisation that the design does not work in practice and most importantly the cost factor. There are some very large and successful layouts, but when you study them, they are usually, in essence, basically simple in concept. All on one level, sensible curves etc, etc. Roy Jackson's marvellous Retford is a case in point. Yet even as experienced as Roy is, he had to rebuild one area of this huge layout. Why? Because he had to include some gradients. These were very shallow by most standards, but he had to make them even more gentle to allow his trains to negotiate them and bear in mind most of his loco's are kitbuilt and therefore have better tractive effort than modern RTR.

If yiur primarily desire is operations , runnng trains , rather then building layouts. I’d suggest you break your track plan down into sections that can be completed within 6 months to provide continuous running. ( that’s 6 months to fully wired track but no scenics etc

 

as for the two layer track plan , you need to really be comfortable with access to the lower track or design it with easy to remove top sections.

 

Personally I’d try and have a layout on a single level , with sections lowered to represent underground etc.

 

All that track work with a further baseboard above it , is a receipe for trouble. Even with considerable intervening height ( ie , 300 mm)

the helix won't work. Radii will be too tight. 

That is very useful detail - thank you. One thought is that the lower level can be operated in a self-contained way, and is considerably simpler than the upper level. I wonder whether it would be worthwhile starting there?

I still feel the lower level is pointless and will cause more problems than it can warrant. Having so much hidden track to serve a very short scenic area is really both a waste of effort and a potential disaster zone.

If you were to just concentrate on the upper level, sorting out the design faults, you could potentially have a very good and interesting layout.

I think we're probably all glad that things worked well enough for the crowd to enjoy it - even the bit when I got a D2 half way into the turntable bit while multi-tasking!

Is that 'bit' of the turntable the Pit?

Ratio make LNWR 50' Arc roof corridor stock in plastic kit format and are relatively easy to put together.  The challenge that you have already alluded to is the livery.  Jol Wilkinson penned an article in MRJ a few years back now on reproducing the LNWR livery on coach kits

 

Current suppliers of LNWR brass coach kits are London Road Models and Stevensons Carriages.  Worsley Works do some too.  And Wizard/51L have a few also.  

 

No connection to any beyond being a customer of every one.  The chances of any RTR stock is very slim

Normally, I'd totally agree regarding rolling stock. However, looking at releases over the last few years, nothing is impossible, however unlikely. the manufacturers and commissioners of models are finding pre group sells well. Though as always any coaches would inevitably be only a representative selection. Usually missing vehicles required to make an authentic rake.   

Thank you all for your replies. That Euston layout is looking very impressive so far - and all with hand built track and locomotives, too! It must take some serious skill and patience to build all the track by hand for something like that. That will be quite splendid when it is done, I am sure.

 

In relation to the position of the station throat - I had considered shifting it upwards a little to slacken the curves, but I thought that that would then make it too far from the edge of the baseboard to be able to reach, and one of the other pieces of advice was to make sure that the more complex things especially were close to the edge of the baseboards. I wonder whether reducing the size of the baseboard at the front in that area might assist? I do wonder whether that would make the baseboards rather unevenly shaped so as to make the resulting well less useful in space than it might otherwise be for the equivalent amount of area. Also, would putting the station throat further up not eat into what is otherwise the only significant uninterrupted space left for scenery?

 

In relation to straight platforms, I thought that these would be significantly easier to model than curved platforms (one can, after all, buy prefabricated straight platforms, which should significantly reduce the work involved in installing them) and would take up less shed space for a given length of platform. After all, many mainline termini do in fact have straight or mostly straight platforms: Paddington's are mostly straight apart from some curvature at the Western end, those of Euston, King's Cross and Marylebone are entirely straight, as are those of Charging Cross, Fenchurch Street and Liverpool Street. Waterloo has some curvature, but mainly at the end, I think, and I think that Victoria is similar.

 

Mightbe - instead of giving the measurements in this thread, I thought that it might be easier just to upload the .scarm file, which is here.

some points you may consider regarding Euston. It would give you a lot of ideas of what is practical if you read through the posts, find the size of the layout and double the measurements. Also of note is his tightest radius, just under the 4mm equivalent of 3' radius. Also, his motive power will all be diesels and electrics, which are always more powerful than steam.  

Hello Mike,

 

In between the grandchildren and the stairs, I did a little (skimmed perhaps) reading on the LNWR. I never realised just how big or powerful company it was prior to the 'Big Four'. It does seem to me that the LMS was in effect the LNWR in all but name.

 

I did want to ask, and I hope you'll forgive me if you're into making locos and rolling stock, where can I get some RTR models that would give the flavour of LNWR running through Pontrilas? I can only see one loco in the Bachmann range that is LNWR  (D2?) and as far as I can tell, no coaching stock to be had from anyone. I did do kits years ago (plastic coaches and whitemetal locos) but what was passible then ....... quite frankly I don't think my skills would be up to scratch when I look at the pictures of some of the finished kit built items out there. (Mind you, I have seen some stuff on the web and I think .....eueuh! Even my kits from 40 years look as good). Time is the main factor here for me (and probably most of us - unfortunately).

 

Regards,

 

Philip

 

PS: Thanks for the laser cut idea - as this is long term I'll put up with cutting strips the same width over and over and over ................. what was that address agaithere 

There are currently two LNWR locos available in RTR, both by Bachmann. The Super D and the coal tank. Currently the only rolling stock would have to be sourced from kits. However, by the 1930's the ratio of LNW locos and stock would be very much reduced with much more Derby and Stanier designs handling traffic.

Thank you for the information. A 3ft (~314mm) curve would along the short side of the room without too much difficulty, but it would not be possible to have a reversing loop in the space with this radius. I note that there is a Youtube video

of a Hornby King hauling 12 carriages without difficulty on an oval layout, although it is difficult to discern the minimum radius of the curves there.

 

I can imagine that it would be most awkward to have to put a turntable in the fiddle yard and set everything up for the locomotives to detach, turn, and run around their trains there.

 

Incidentally, in relation to the very last reply, I repeat what I have stated above and what should be clear from the diagram in any event: all of the tight curves on this layout are either in yards or non-scenic areas.

I give up. I forecast that should you follow the path you seem keen on, within a year you'll either opt for something more sensible or there'll be a lot of stuff hitting ebay

You may also consider that, aside from operating limitations, any mainline with curves much under 3' radius looks faintly ridiculous and toy like. Especially with the need to space the lines further apart to set track distances.

I'm glad the shots of the DE area meet with approval, as I still have more.

DE 7.JPG

There is something in that picture which needs toning down. We also have a different angle on the high level view looking South.

shed yard.JPG

The thing that jumped out at me as needing toning down was the coupling loop. Great pics as always though

Congratulations Tony. Richly desrved

I suppose you could always double head your longer trains

The sensible option is to build a sensible layout using decent radius curves and not fill every square inch with track.

Yes, the plan is for a 1930s era layout in the GWR era, meaning mainly 4-6-0s for the longer trains. I think that I might have to conduct my own tests at some point with a suitable 4-6-0, a long rake of coaches and some track temporarily laid on the floor (settrack, perhaps) to see what can be achieved so as to calibrate the constraints for design: I will have no way of actually coming up with a workable revised design without having actual numerical data for the constraints within which I must work to get reliable running.

 

(Incidentally, I wonder whether the tender drive locomotives had better or worse traction? I have some old tender drive locomotives in the loft).

 

Incidentally, was the problem wheel slip? Two possible ways of dealing with this might be ballasting the locomotives and using steel track for the tight turns, but I do not know how much that this would actually help nor how much ballast could actually be fitted into a DCC fitted locomotive.

My under construction layout has a maximum capacity of 8 coaches. When laying out the design I carried out some tests. On level track none of the RTR GWR 4-6-0's as bought were happy with 8 coaches on a 2' 6" radius curve. All slipped to a greater or lesser degree. On a 3' radius the were all pretty happy, though a couple didn't like starting a stationary train on the curve. This was on level track. I will add weight to mine, but even then I doubt they would be too happy with 10-12 coaches on similar radii. Fortunately for me, most of my loco's are built from kits or scratch and are easily up to pulling big heavy trains.

To get long (12 coach) trains around tight curves will be very problematic. Apart from the power of the locomotives, the other factor is making the coaches free running enough. Ordinary rtr will need to tweaking.

 

The best example that I can find dates back more than 50 years, the early 1960s, Ken Northwood's North Devonshire. He could get an 80 wagon freight train around a 2'3" radius curve. By changing your layout design a bit, you may be able to do that, although it would need some gradients.

Ken Northwood built seriously heavy and powerful locomotives. Not a good comparison at all really  

Thank you all for your replies. Firstly, to answer the query about the top right hand part of the track plan: the part between the tunnel entrance and the slip connexion is intended a gradient (which gradient continues inside the tunnel), so that, by the time that the tracks connect to the slip, they are level with the main line. The crossover is intended to be part of the gradient. The SCARM calculations showed this gradient to be circa 3% (although it is difficult to be exact as SCARM does not allow points to have a different elevation at one end than the other). As I have mentioned before, the plan was for only shorter trains to use the gradiented sections: all of the longer trains would remain on the flat.

 

Thank you for the information regarding curve radii and long trains: this is most helpful. It may well be that adding weight may be necessary in some cases. Can anyone suggest a suitable minimum radius of curve for a non-scenic area for long trains (circa 12 carriages) in OO gauge that can be achieved if the locomotives can be suitably ballasted?

 

In relation to a starter layout, I have been giving some thought to what might work best. I am currently attracted to the idea of an N gauge layout set in the late 1980s (which is something that I should probably want to build in any event), being an intermediate sized through station on a main line in the Western Region, featuring some basic carriage sidings and locomotive stabling facilities for semi-fast locomotive hauled trains to turn (as in Oxford). I should probably have wanted to build a layout conforming to this description in due course in any event, as this depicts the time and place when and where I was growing up.

 

A question is how best to fit this into the proposed shed leaving room for a larger OO gauge layout on a different level. I was considering having this occupying the whole of the wall opposite the windows (but not going around a corner), with space either above or below for the eventual OO gauge layout. Has anyone any suggestions about how to set this arrangement up so that the two layouts do not interfere with one another (e.g by the supports for the higher layout getting in front of the lower layout) and both are at a sensible viewing height? Is there a way of having an adjustable height shelf on brackets affixed to the wall, I wonder, so that the layout can be pushed up when not in use or to work on the electronics and pulled down when in use?

 

I will have a go at designing a track plan for this simpler layout and posting that in a separate thread when I get the time.

having a change of gradient in the short distance between the slip and the crossover is a disaster waiting to happen. This plan is not only too crammed and ambitious it is effectively unworkable. I implore you to set more realistic goals before you shell out 8 grand or more on just baseboards and track to end up with a pig in the poke.

Thank you all for your replies. Firstly, to answer the query about the top right hand part of the track plan: the part between the tunnel entrance and the slip connexion is intended a gradient (which gradient continues inside the tunnel), so that, by the time that the tracks connect to the slip, they are level with the main line. The crossover is intended to be part of the gradient. The SCARM calculations showed this gradient to be circa 3% (although it is difficult to be exact as SCARM does not allow points to have a different elevation at one end than the other). As I have mentioned before, the plan was for only shorter trains to use the gradiented sections: all of the longer trains would remain on the flat.

 

Thank you for the information regarding curve radii and long trains: this is most helpful. It may well be that adding weight may be necessary in some cases. Can anyone suggest a suitable minimum radius of curve for a non-scenic area for long trains (circa 12 carriages) in OO gauge that can be achieved if the locomotives can be suitably ballasted?

 

In relation to a starter layout, I have been giving some thought to what might work best. I am currently attracted to the idea of an N gauge layout set in the late 1980s (which is something that I should probably want to build in any event), being an intermediate sized through station on a main line in the Western Region, featuring some basic carriage sidings and locomotive stabling facilities for semi-fast locomotive hauled trains to turn (as in Oxford). I should probably have wanted to build a layout conforming to this description in due course in any event, as this depicts the time and place when and where I was growing up.

 

A question is how best to fit this into the proposed shed leaving room for a larger OO gauge layout on a different level. I was considering having this occupying the whole of the wall opposite the windows (but not going around a corner), with space either above or below for the eventual OO gauge layout. Has anyone any suggestions about how to set this arrangement up so that the two layouts do not interfere with one another (e.g by the supports for the higher layout getting in front of the lower layout) and both are at a sensible viewing height? Is there a way of having an adjustable height shelf on brackets affixed to the wall, I wonder, so that the layout can be pushed up when not in use or to work on the electronics and pulled down when in use?

 

I will have a go at designing a track plan for this simpler layout and posting that in a separate thread when I get the time.

To run the kind of trains you envisage you should be looking at 2'6" as a bare minimum radius and preferably more. This isn't an arbitrary figure but one gained through experience. Too be quite frank though, I would seriously suggest you pull back on your ideas. You are trying to cram far too much in the space you have. Even in a larger area it would be seriously unrealistic for one person to build, let alone to finish and maintain. You could still get a decent version of your concept, but one simplified. It would also look better and more importantly be achievable. 

I said "steepest workable for small trains"...

 

Railway Modeller magazine state that 1 in 36 is the steepest recommended gradient for OO layout designs submitted to them for publication.

 

I realise that there are lots of different opinions about gradients and what's workable very much depends on individual circumstances like rolling stock, train length and the radius of any curves.

 

BTW: I think James said that only shorter, underground trains were intended to ever traverse his proposed inclines - not 10-12 coach mainline traffic...

As I said, it is not just gradients. The proposed layout is using tight curvature effectively set track. Most modern RTR loco's will balk at getting long trains round them, even on the level. Again, my under construction layout has the main area on the level, 3' minimum curve max 8 coaches and many RTR struggle to pull a train while on the curves and that is 3' radii. I can get round this by using predominantly my kitbuilt stud, adding weight or rebuilding ready made, and in extreme cases building new chassis. I realise though, that option is not always open to many modellers.

I said "steepest workable for small trains"...

 

Railway Modeller magazine state that 1 in 36 is the steepest recommended gradient for OO layout designs submitted to them for publication.

 

I realise that there are lots of different opinions about gradients and what's workable very much depends on individual circumstances like rolling stock, train length and the radius of any curves.

 

BTW: I think James said that only shorter, underground trains were intended to ever traverse his proposed inclines - not 10-12 coach mainline traffic...

I have a branch on my under construction layout. The maximum length that would be using it is 4 and occasionally 5 coaches. Since part of it is on a curve, I found after experimenting, that i had to run the gradient over 7' in order for RTR GW and Southern 4-6-0's to happily negotiate it. Said branch is only rising 3 1/2 inches and the curve is a tad under 3' radius. Fortunately most of my loco's are heavy kitbuilt, but I also wanted to be able to use a few RTR loco's.

Hi James,

 

There's nothing wrong with ambition if you've got the time, money and drive to back it up - and 2500 by 7500 mm is a good space to do something impressive in!

 

But as you are finding, even a relatively large space requires compromise and clever design to accommodate a good model.

 

One of the arts of railway modelling, one of "black arts" perhaps, is how to compress the real railway beyond simply scaling down prototype elements and yet still give a believable representation of the real thing. (Of course, if your main interest is operation then perhaps realistic appearance may be further down your priority list.)

 

For instance, where a terminus might have 10 platforms in the real world, maybe modelling 6 would convey a good sense of the prototype and 6 coach mainline trains may look entirely believable in a model.

 

138mm between levels should be fine for OO - the minimum is generally thought to be 100mm (depending on your baseboard construction method). 1 in 36 is usually reckoned to be the steepest workable incline for OO - and that only for small trains.

 

See if you can find a copy of C J Freezer's "Plans for larger layouts". It should be inspirational but be wary of his stated minimum radii - they are often tighter than perhaps we would be comfortable with these days.

I'm sorry, but you are wrong regarding gradients. Most RTR locomotives struggle on all but the gentlest of grades. Add curves into those grades and they'll simply slide to a hault. 10-12 coach trains would be impossible. In fact, I doubt most would even haul them on the flat with the radii being considered here.

Thank you all very much for your replies: that is most helpful. Again, I will respond to some of the more specific points before moving onto the more general issues.

 

Firstly, in relation to the number of operators, that is not an issue in itself, since I had stated in the original post that I was interested in computer automation. Secondly, as to the curve radius, I made sure to set a minimum curvature in SCARM of a 438mm radius, which equates to a second radius curve. None of the track in this plan has a lower radius than 438mm. Small radius Streamline points are specified for the hidden areas, but all of the scenic areas use only large radius points; likewise, the tight curves, apart from the depot, are all in non-scenic areas (denoted by green/yellow on the plan), so looking akin to a train set is avoided by that expedient. Thirdly on the specific issues, the gradients were not intended to be used with the long trains: the idea was for them to come into the terminus on the flat, the gradients being used by trains descending into the LT lines, which would generally be shorter trains. As to the idea that suburban trains are shorter than long-distance trains, this varies by region; I know that some places have very long commuter trains (all the former Southern network into London, for instance), which are just as long as the main-line trains on that route, but I was interested in Great Western, where 5 (sometimes strengthened to 6) was the normal number of carriages in suburban trains. I should also note that the plan did specifically provide for a 1.1m wide workbench (notice that the baseboards are longer on one side than on the other side for this reason).

 

In respect of Jonny777's comments, my plan was perhaps a little unclear: the blue lines are intended to be electrified, not at a different level: the difference in level is intended to be represented by the two different layers, so some of the blue lines would be visible on the lower through station, which was planned to be visible from the side even though it is underneath the terminus (it is intentionally close to the edge of the baseboards to be more visible). As to the turntable, I could not find another way of fitting it into the space available.

 

I do not think that I could sensibly build just the blue (i.e. electrified) parts of this specific planned layout: the plan is loosely inspired by Paddington (hence the main and relief lines separated by use rather than direction, the short suburban platforms, the extra long platform at the southern end, the Hammersmith & City dive-under at the Western end and the tunnel beyond the Eastern end then joining with other Underground tracks from a different direction, etc.), and the blue parts denote electrified (fourth rail) lines; the suburban platforms are mixed use for terminating trains and those continuing into central London, and there were many trains that were operated by being steam hauled into Paddington and then changing to an electric locomotive at that point for their onward journey (and the same in reverse). I do not think, therefore, that the Underground lines in isolation would be workable here.

 

However, turning to the more general point, I do see considerable force in the point that, if I have not done much of this recently, I really need to get a feel for how to do it and what is achievable by building something smaller scale before considering a larger scale project, so that I can have a better idea of what is feasible, and that doing so may well avoid what might transpire to be costly mistakes, as well as not postponing the enjoyment that  might be had from such a project until a very large and complex thing has been largely completed. One thing that I am considering, although I am not yet sure how this might work, is to build a more interesting version of the lower level station in the plan first, and then consider later a possibly simplified version of the upper level of the plan. One of the main constraints in the vertical spacing which I can see being problematic is caused by the need for the lines going underground to do so at two points: firstly, to rise from the dive-under at the western end, and then descend again into the eastern end. An arrangement in which only one of these inclines is necessary means that the whole of one side might be used as an incline, allowing twice the vertical separation. Certainly, I am very attracted to the idea of a small layout that could then be incorporated into a larger layout at a later time, and share the stock, or at least much of it; but if I am to do that, I will need to know what will actually fit into the eventual larger layout, and therefore to plan that in detail, too.

 

I note with interest the comment along the lines of "more Marylebone, less Victoria": when I was contemplating a layout in the attic, I had designed an entirely different plan, but incorporating some of the elements here (long platforms - there only long enough for 10 carriages, Underground lines serving separate platforms at the non-terminus end of the station and then a separate further Underground station beyond a scenic break, the additional distance being simulated by the trains automatically pausing in the intermediate tunnel for the amount of time that it would take to traverse the several kilometres to the next station, and an engine shed and carriage sidings) which I had called "Maryington" as it was inspired by a sort of cross between Paddington and Marylebone. That had 9 platforms plus the two suburban platforms, and was still very intensively covered with track, although I later realised that some of the curves on that plan were of the same radius as first radius curves and would have been too tight for much of what I wanted to use there in any event. One possible difficulty with a Marylebeone inspired layout is a relative lack of ready to run stock used on the Great Central - from what I found out when I looked into the matter, the LNER largely continued to use old GCR locomotives and carriages on the line. In particular, there is a lack of suitable suburban passenger engines and carriages.

 

As to using all of the space, the reason that I did this was because space, especially linear space, is notoriously the most significant constraint in railway modelling. Thus, a layout that can take full advantage of the available space is one that will be less constrained than one that cannot. We all have our own preferences as to what compromises to make, of course, but I find unrealistically short trains and tight corners in visible parts of the layout to be particularly unsatisfying, which is why I designed the plan attached to my first post to have the corners mostly behind the scenic break, and to have long platforms and carriage sidings.

 

In terms of simplifying/redesigning, it would help me to know a little more about some of the constraints within which I ought to work in order to achieve something workable. The maximum width beyond which it is difficult to reach items is useful to know (900mm was suggested; I am fairly tall (6ft 1) and thus have fairly long arms, so might 1m be workable). Several have mentioned the time taken to lay track; can anyone estimate how much track can be laid in a given amount of time? In terms of wiring, is there a maximum density of some sort which can sensibly be expressed numerically that it is preferable to observe to avoid unworkable wiring?

 

I am definitely keen to have some sort of main line terminus with a mix of suburban and long-distance workings, carriage sidings and an engine shed (subject to having a go with a smaller layout first which might hopefully fit into the larger layout in due course to gain experience). Perhaps reviving the Maryington idea for a larger space might work, and have the suburban lines shared with the Underground (as on the LTSR), reducing the number of lines coming into the station, and also reducing the number of platforms, perhaps.

 

In one sense, I am rather tempted to buy a small train set with DCC (and the higher quality stock), set it up on my floor and see how that works out (and test various DCC control options), but I will need to know that I will not be buying stock that I will ultimately not be using, which, in turn, involves planning what I actually will be using. That also has the difficulty that I suspect that one cannot set up point motors without fixing track to baseboards (or else the motor might move instead of the point blades), so testing the wiring and control of these things might have to await a shed in any event.

 

One other thing on which I am keen in the longer term is to be able to model what is probably my favourite period of railway history, the Edwardian period. This has to be a long-term project, as I will need to acquire the skill to build stock from kits/3d prints, as there is not enough ready to run stock available from that era, but I should ideally want a layout that could equally plausibly be set in the 1930s (so that I can use my lovely old Harrow Models Q38 cars - albeit they were not called Q then, of course) and, with a change only of stock (and perhaps one or two strategic and easily removable scenic items such as road vehicles), have it represent the period circa 1910.

 

In any event, thank you all for your various replies: it is most helpful. I am definitely leaning towards the small then large approach, but need to think carefully about (and would appreciate anyone's thoughts on) how the one might best relate to the other to avoid duplication (I am especially keen on the idea, surprisingly seldom exploited in railway modelling from what I can tell, of having two separate stations on a layout, separated, not by a scale distance, but a scenic break and a computer controlled pause to simulate the scale time to traverse the distance between them, the smaller station being suburban in nature and the larger station a main line terminus; so this gives the somewhat obvious possible solution of starting with the suburban station; but how best to do that is another matter entirely).

I'll give you one, very basic, reason your plan will not work, aside from the fact it is effectively over ambitious and far too complicated. Gradients, especially gradients on curves. You state 10 coach+ trains. Most modern RTR locomotives will just slide to a halt. Simple as that