Common SSL Stock & New Track

And never underestimate it. One of the things that attracts me to LT, as an enthusiast, is the generally excellent state of the ballasting. (Yes, I know there are bad spots, but the overall standard is high, and on many stretches it is impeccable.) But I am concerned that the 'flatbottom and pile the ballast high' school could be perpetrating some myths. If those S stock (or whatever it will be called) bogies, which I assume will be low weight, are reputedly going to "bounce off the [bullhead] rails", then they will fare little better on flatbottom, and there is something inherently wrong in such an S stock design strategy in my view if that is the case being presented.

Concrete flatbottom is heavier than wooden bullhead, and even though LT axle loadings are comparatively low, I question the assumption that bullhead 'moves' more than flatbottom (although a degree of vertical 'cushioning' is highly desirable in any permanent way practice). Badly maintained flatbottom is just as much a problem as badly maintained bullhead. Concrete track, if ballasted as per network rail practice, requires more, not less, ballast compared to bullhead. Continuous welded rail is a definite advantage for any track type, but LT will I think be characterised for many years to come by comparatively tight turnout architectures - there simply isn't the space in many cases to ease the radii, and using welded-up track joints where fishplates are currently the norm near junctionwork will increase the time taken when track replacements and repairs are needed, and will result in tracks being out of service for longer periods of time. Replacing a whole ballast bed is a very time-consuming process. (How fares the new Piccadilly west of Barons Court, btw?)

I am trying not to be a luddite here, and I am conscious of the pressing needs of modern economics in track renewals, but track requires good ballasting and regular maintenance. Passengers are unlikely to warm to the concept of lines being closed for extended periods of time. 'A little and often' was the old ballasting way, and there is much to be said for continuing the practice.

It's high time that LT took its infrastructure back under its own wing, and started doing things that are right for London, rather than playing along with the devious schemes of Metronet's accountants.

Interesting post, Colin.

Rant over!

Russ

when they come to re-new the track more so at the east end of the district past whitechapel the types of points there (chairlock) will not fit a flat bottom rail so either they will have to keep the bullhead around the points or have a huge investment to replace the points with a 4' flat bottom design of points ( like glouchester road area )

[cynic]

Hope it's better than the one on it's Swedish cousin... ;D

see here to see what I mean.

(And yes, that is a fairly standard Air-con unit).

As for the difference between in NR and LU track, I certainly used to notice if I had fallen asleep on a Richmond train when coming home in the mornings. ;D

Granted I think you probably had one of those p-way chaps who knew more or less what he was talking about. Was he "old school" or had he simply slipped through the net.

I'm used to p-way chaps like the one last night who asked why the points had moved during engineering hours just as he was about to move his trolley over them. Well, I said, for one I didn't know you were there, and two, nor did the TO working on the frame in the IMR you walked past to get to where you are now.

He wasn't old school - but I think he learnt his trade from someone that is or was. He certainly seemed to know his stuff, and is very aware of all the bad spots on the District line, and possibly others.

As for the slab track, Q8, I could be wrong here - but I thought that was just a term to describe sections of track already put together, and just waiting to be 'dumped' into position (?).

That sounds like a most sensible idea, i have noticed looking at the track that has been laid for Chiltern Railway from Hamstead to Harrow on The Hill that there are some metal sleepers. These look really thin, now forgive my ignorance but i thought that sleepers were of a certain depth so that you could pack the ballast around them tightly. These metal sleepers seem so thin that they alomost sit on top of the ballast.

Hmm Ho should i say "now whats all that about?"

slab track is around the westminster area since the re-done the station

There is a huge pile of them near my station. They appear to be a little more than just bits of metal. They are shaped to form a "cupped" underside and have much stronger looking fixings on the rail side.

Maybe the shaping is the key, and maybe the design means it can "hold on onto" the ballast rather than the ballast holding on to it.

AFAIK the S stock will have welded bogies - recreating the original cracking problem - unless the track is improved.