Edwin_m

That picture confirms the China-built Class 91 is of similar construction to the other split-chassis China-built locos featured in this topic. I guess the lower roofline for the pantograph means there is no room on top of the chassis, and the chassis itself also takes up most of the space between the bogies. Is there room for a small decoder in the blunt end cab? If necessary you could look at something like a Zimo MX621 or a CT decoder, both of which are very small and have an excellent reputation, but will cost more than the likes of Digitrax.

Are you referring to the Poole-built version? As I understand it, and as implied by prevous posts, prior to the introduction of the PCB/DCC version with the Class 66s all the China-built D&E models except the 08 and the 20 used variations on the same split chassis concept.

I've done a 47 (pre-2009 version) and several 158s and 170s. All were still very quiet after conversion, but I didn't have to remove any of the chassis apart from the small parts over the two brushes. Have you had to remove more on the 91? Also have you fully tightened the screws and included all the spacers - there's probably supposed to be one underneath the motor?

I agree with that. We need to know if the busway is workable before too many others embark on similar schemes. That doesn't follow. If they'd followed the same contractual process to deliver a railway then they'd probably have got themselves into a very similar situation, just as the Edinburgh people have with the tram. And as to heavy rail, how long did the Robin Hood line take even with all local authorities and industry bodies fully behind it? I hope you're not suggesting DfT would be a better option! Consider for example Manchester Metrolink, a much larger transport project also being run by local authorities, and shaping up to deliver pretty much what was promised.

As I think I posted further back, both the busway and Edinburgh are suffering from disputes between the contractor and the local authority sponsors. This type of problem can occur with all sorts of civil engineering projects and there's no particular reason why a busway is more likely to suffer this type of delay than any other transport system. Very much still in use. See this list of busways.

Your diving loco wasn't a 66 perchance? I find, with the Farish ones at least, that the lifeguards that project downwards ahead of the wheels will catch on the slightest upward step in the rail and stop the train dead (amazingly not snapping the lifeguard!). Regarding wobbles on points, these seem to be unavoidable for current British N gauge stock on Peco pointwork - something to do with the points having to accommodate older and coarser wheels I think. I've had interesting events where the front of a train being propelled catches in a point but the loco carries on by compressing all the coupling springs, until the resistance is overcome and the front end suddenly jumps forward.

Remains of one here (I think) between Aldwarke and Swinton.

The depth of the decoder is critical unless you plan to mill out a piece of the chassis. The space available under the roof varies between the different models but is small on most of them. May be a good idea to make a block of Plastikard to the correct dimensions for the decoder you are interested in, then stick it temporarily to the chassis and see if the body goes back on properly. If the dimensions are OK I'd look at the Digitrax DN135 only from Digitrains, or failing that the DZ125 from most suppliers.

Looks excellent and I hope you can capture in N the reel feeling of space as seen on the prototype picture - I'm assuming the likes of Drem and Law Jn are amongst your inspirations. Would it be better to rearrange the fiddle yard a bit so there are central bi-directional tracks for MUs and HSTs which can arrive/depart on either line without fouling the other track? Outer uni-directional tracks would be for loco-hauled.

I am guessing this is an example of the Beeching-era thinking where they assumed that buses would replace local trains wherever possible. Tavistock has a direct road link to Plymouth, which wasn't congested at the time, so it was considered that the bus would be an adequate public transport provision. Due to the lack of road bridges over the estuaries, a bus service to Gunnislake (or indeed Bere Alston and Bere Ferrers) would have been very difficult. I rather doubt anybody would drive from Tavistock to Gunnislake to catch a train, since it is almost setting out in the wrong direction and the train journey from Gunnislake back to Bere Alston is slow. Even with the traffic jams it is probably better to head straight for Plymouth. However a train service to Tavistock might divert some people from the area between the two stations to park there rather than at Gunnislake, especially if the Tavistock service was significantly faster or more frequent.

IIRC from looking at this about ten years ago, there was one house blocking the formation on the very southern tip of Tavistock and the bridge over the Gunnislake road had been taken out. I think one small underbridge was also missing between there and Bere Alston. Hence the proposal at the time was to put the station on the southern fringe of the town, which would have given space for a car park but been an inconvenient walk (uphill one way) from the town centre. In my view much of the Park and Ride traffic would be in competition with Gunnislake which has another P&R further down the same road. Apart from this one house the trackbed was clear up to the viaduct, where a single-platform station would be possible and nearer to the town centre. No car park of course and the walk to the station would now be steep uphill. I did suggest a lift up the side of one of the viaduct piers but I suspect the heritage people wouldn't wear it or it would cost too much... I emphasise this was ten years ago, I'm not aware of what has been proposed since then or whether anything has changed on the ground.

Another option is to make the trains and infrastructure both capable of a higher speed but only use the maximum speed when recovering from any delays. Having this sort of margin is also useful on hilly sections where the train might otherwise have to brake (and waste energy) on the downgrades to stay within the limit. I agree with Allegheny that in general a higher design speed won't add that much to costs. The exception is where the larger curve radii makes it more difficult to thread the line between villages or other places that must be avoided. In the extreme this could mean more tunneling to go underneath such sensitivities (and incidentally aerodyanamic losses are much higher in tunnel). Difficult to know where this might have come into play going by the end result, but no doubt this information is available somewhere in the design documents.

In previous discussions we have established that the number of air passengers between West Midlands and Paris (the most likely beyond-London market) is too low to justify more than about one train per day, and is of course distributed over various times of day so that one train would not be convenient for all of them anyway. The only workable model for through services is that used by every other international train service, where the train also serves domestic markets in the countries it passes through. Unfortunately security rules make this virtually impossible where the Channel Tunnel is involved, so we are probably stuck with a change of train somewhere in London area including the security checks. As Ron says there is a strong argument for not going all-out for speed on HS2 - whatever speed it operates (within reason!) it will be the fastest way between London and Birmingham. If and when it extends to Scotland speed may become critical for competitiveness, depending what the aviation and general travel markets are doing in 20 years time. So it is wise to do what they seem to be doing and design for a very high speed where practicable.

A clickable plan has now appeared on the BBC website.

The intention is to build two fleets for HS2. One would be euro-standard trains that can be relatively easily purchased but would be limited to running on HS2 infrastructure. There would also be a fleet of dual-purpose trains that could run not only on HS2 but on the conventional UK 25kV network. Eurostar could do this role with some modifications but by the time of HS1 running would be over 30 years old so not worth converting. On day 1 the euro-trains would work London to Birmingham and the dual-purpose fleet would work to other WCML destinations. On completion of the Manchester and Leeds extensions more euro-trains would come into use and the dual purpose fleet would be re-deployed from London-Manchester to services such as London-Newcastle.

True, but this wouldn't allow for the issue of luggage screening which we appear to be lumbered with for trains using the Tunnel whether we like it or not. Any passenger boarding a train heading for the tunnel would have to undergo some form of screening in case they left an item on the train or passed it to a passenger making an international journey. I suspect the need for photo ID is part of the same process, "security" being deemed to include knowing and verifying the names of all passengers just as it now is on domestic flights. Including the security checks in a change of train at Euston-St Pancras or Old Oak is probably the closest we will get to a seamless international journey from further north or west. As others have posted, low cost airlines also make a mockery of the finances of any longer-distance train service international or otherwise, for business travellers above a 3hr rail journey time and for many leisure travellers too (although probably at a longer time threshold). It may be argued that the tax on jet fuel and other aviation activities should be very much higher to reflect environmental damage, but the likes of Ryanair are now very much entrenched in our society and I doubt any politician would wish to be seen denying the general public their right to a cheap holiday.

There's a couple sitting in Longsight depot...

If you have a house move in prospect, even in several years time, then it's probably not a good idea to fill your loft with a layout that almost certainly won't fit into the new house without heavy modification. Unless you have a lot more free time or you're a much faster worker than me then a large layout will be nowhere near finished by the time you move. So I'd agree with Kris to make something that is not too ambitious and can easily be moved to a new place. For example if you make the layout less than about 4.5m by 2m (smaller if viewed from the outside) then it will go in a single garage, or half a double garage, and depending on your circumstances you may well be able to get the use of that space in the new house. The other option might be to build something like the suggested layout, but make the scenic part in a modular form so it can be included in a larger layout later. I'm probably biased but I think your eventual ambition to model much of the Wolverhampton area would fit better in N, unless your new house has a spare barn attached!

European specifications require high speed lines to be built to accommodate trains 400m long so as to be available to any train that might want to use them.

On the drawing linked by Andy the HS1-HS2 link appears to join the two main tracks just outside Euston/St Pancras but continues as a third tunnel (presumably single line) all the way to Old Oak. Not sure why this should be, having a junction in the tunnel would seem to be both cheaper and more flexible. I must have a look at these in more detail. Level crossing don't feature on any of the European HS routes as far as I'm aware, one of the main reasons for the excellent safety record of these routes, and I don't think anyone would seriously consider putting them on HS2.

That's a natural consequence of the process. The engineers will have chosen the best alignment in engineering terms, taking account of the environmental constraints that were considered important at the time. Now it has been decided that there are more environmental issues to worry about, extra engineering is required to get round (or under) them.

I think you should shorten the bay a bit and move the facing crossover to beyond the points where the bay joins the through lines. This will allow a train to enter the bay in order to reverse there. Otherwise it would have to drop its passengers in the top platform then shunt. There are precedents for this (Lincoln until recently) but for a modern layout the direct running option is far more likely. Sorry I seem to have been banging on a lot about bay platform crossovers on this thread! I'm also not sure the trailing crossover is needed and I still don't like the crossovers in the middle of the platforms. If the sidings going to the right are goods then it is far more likely they would face the other way so a goods train going anticlockwise could shunt in. The TMD could be on a "kickback" arrangement instead.

Might be easier just to have an autocoach running into a bay like the Brixham shuttle from Churston? Then the shuttle could wait in there if there were through trains to the Town station, and could run to and from the branch independent of moves on the main line. Of course if you want the operational interest then go for the shunting option!

Burying the bottom of the code 55 in the sleeper base means that the visible fixings on top of the sleepers only need to be cosmetic, unlike code 80 where they have to actually hold the rail in place. Hence the "fixings" in code 55 can be much smaller, which makes them look more realistic but also means a deeper flange can be used than if they had used a genuine code 55 rail. All in all a clever bit of design, the only major drawback I can think of is that the point blades revert to code 80 and are therefore a bit conspicuous. Minor niggles are that shiny bits of the "hidden" rail show up in gaps in the webbing, and are difficult to paint, and that you can't run orange cable pipes underneath the rail.

In principle there would have been scope to use the line as a much shorter route between Cambridge and Peterborough, thus improving the passenger service and making it easier for Felixstowe-Nuneaton freight to get onto the existing route via Ely. However I think the route west of St Ives has been lost and it would be very difficult to re-connect to the ECML near Huntingdon.