Rods_of_Revolution

Here's a before/after type GIF, though not perfect as the webcam has been adjusted in the mean time. It looks like a section of wall at the far end has gone and some of the containers have buckled.

Cheers,

Jack

More bad news - it would appear the line of containers has been breached:

 

http://www.itv.com/news/westcountry/update/2014-02-14/dawlish-railway-shipping-containers-breached/

It's not surprising, there's not much to stop the containers shifting under the force of the water. It'll still be better than if they weren't there at all, hopefully not too much hard work will be undone!

Regards,

Jack

Looks good mate! I especially like the side door open so you can see the stock rolling past! The brickwork also looks spot on!

Hopefully you find the enthusiasm to get the layout moving, I don't want to be waiting another 3 months for the next installment!

Cheers,

Jack

Point taken, but compare a concrete driveway to a gravel drive. Even if the concrete drive has a drainage channel (which it obviously should), which driveway drains quickest? IMHO, just because slab track is a modern solution, doesn't make it best or even better. Usual disclaimer that not being a civil engineer, I could well be talking out of my a*se, it's just an opinion!

The thing to keep in mind is not how quickly the water disappears from view, but the damage it does. Ballast will wash away and the ground below will become saturated with water, which compromises the stability of the ground. Although the water appears to drain quickly through the ballast it's still doing damage, not to mention the ballast will be washed away and the track will shift.

It might be that water will be visible on a concrete surface longer, but generally it will fall along a gradient and into a channel and it'll drain back into the sea. It's possible the drainage system will be overwhelmed, but even if that happens water will only collect to the point that it begins to flow over the wall and back into the sea and once the storm abates it'll drain away quickly leaving the track in situ and undamaged (probably the biggest advantage to slab track vs ballast and sleepers). There are concrete quaysides at tidal berths across the globe and the drainage is well managed and effective, there's no reason the seawall couldn't be the same.

Whilst working in the field of marine engineering I haven't been involved specifically with designing drainage, but I've been seen enough drawings and specs of such systems to know they are effective.

Cheers,

Jack

Yes, I just had a look. The screen grab from the webcam is probably the last decent daylight image today. It also goes some way to explain that non-draining slab track might not be the best idea for this location!

 

grab01.jpg

That's because the Victorian seawall design does nothing to stop overtopping. Modern Concave designs eliminate most overtopping.

It's worth noting that slab track is not non-draining either, all such concrete areas have drainage built in (even a simple driveway in front of a house does) and if designed properly it's very effective.

Cheers,

Jack

Hi CME,

I have only just found this thread, though I've been following, as you know, on the Western Thunder forum. I especially love the weathering on your wagons, that close up of the mineral wagon on the first page could easily be a prototype detail photograph!

I certainly think options C and D are the best, I can imagine the more pointwork in the garage the easier to maintain and more reliable it will be.

Cheers,

Jack

It should be pointed out that whilst the amount of CO2 being put into the atmosphere is accelerating, the sea level increase is not accelerating, which would seem to indicate the two are not as closely linked as a wind-farm salesman would tell you; so don't think that being "green" will make any difference to the problems at Dawlish!

When the line at Dawlish was built the yearly sea level increases were similar to today, so it was probably understood there would be an increase in problems as time went on. It seems to me that the sea wall route was chosen because it was cheaper in the short term than all the earthworks that would have been required to take the railway across the South Devon banks. Of course, the lessons were learnt and it was proposed to create an avoiding line in the early 1930s, but the war came along just as work was starting on the new route and halted the work.

Cheers,

Jack

Don't feel like you'd be treading on my toes with Pontsmill, the more the merrier!

You mentioned Drinnick Mill, I have often thought this would be an interesting location to model, in a condensed form! I like the idea of a class 37 with a couple of polybulks creeping between decrepit old clay buildings!

Not sure if you've seen this link but it shows Drinnick Mill nicely: http://www.cornwallrailwaysociety.org.uk/clay-country---parkandillack-branch.html

I would imagine having Kiln 5 (older coal fire style) at the left side front, this would be the left hand scenic break, then I'd have the Drum Drier (more modern sheet building) as the "served" building on the layout. The right hand side I imagined including the over bridge as the scenic break, but also some how including a representation of Nanpean Wharf in front of the fiddleyard. As for the coal siding I haven't quite worked that one out, although the siding looks raised, the siding is level! The adjacent tracks actually drop away on a gradient of 1 in 30 something, steep! I guess on a model there would be a gradient at the start of the coal siding which would level out for the drops? Just ideas!

Here's OS Map of the area in the late 70s:

Reproduced by permission of Ordnance Survey on behalf of HMSO. © Crown Copyright. All rights reserved.

Hopefully this is of some use!

Cheers,

Jack

So how long would it take to put the whole of the four mile seawall section on piles?

Too many variables to put an accurate time frame on it. If we are to expect more unplanned closures such as the one we're in presently in then I'm sure sufficient planned closures could be justified and implemented across a period of years to complete the work.

Cheers,

Jack

I had wondered about the merits of having the railway self-supporting using piles but how would this tie in with the structural integrity of the sea wall itself? I'm not familiar with the actual design but from the pictures it looks like the railway is supported on what is essentially the back-fill for the current sea wall. If piles were sunk for mounting the trackbed on, would these be a separate system or would the piles form part of the sea wall structure and the concrete wall be tied to the piles somehow? If they were part of the structure, would a failure in the sea wall also cause a failure in the trackbed, leading to the same situation we have now?

 

My guess would be the best solution is to have a new modern sea wall mounted in front of the current sea wall, using the current sea wall as it's rear mounting face. How practical this solution would be from an engineering and a visual perspective is something for those with more knowledge than me to answer, but it looks to be the best way.

 

Mark

It depends, the current seawall is a flawed design because it allows excessive erosion to occur at the toe of the wall, especially in stormy seas, that being the case it may be better to keep it structurally separate to trackbed. It would be possible to have tie-rods connecting the track slab and piles to the wall, but should the wall collapse it would effect the structural integrity of the trackbed.

I would personally have them structurally seperate, so should the wall fail you'd be left with a concrete slab standing upon concrete piles with the track unmoved. It would then be a case of replacing the lost the material around the piles; once the material was replaced trains could run over at a reduced speed whilst wall itself was rebuilt. It would probably be possible along the open sea section to have piles substancial enough to still allow running even if much of the backfill was lost.

The existing wall could be integrated into a new seawall assuming it is still in relatively good condition. The most important thing is changing the shape of the face from vertical to concave and providing a more substantial foundation to prevent collapse even with a certain amount of undermining.

Cheers,

Jack

You could completely replace the whole 4-5 mile open sea section of the sea wall with a modern design of sea wall for about £40 million or the whole sea wall for about £100 million. It's a far more viable option than opening or reopening other pieces of railway with a cost in the hundreds of millions. A new sea wall would reduce the on going maintenance costs to little more than a standard section of railway.

Regards,

Jack

I'd love to hear the thoughts of the Captain and any other civil engineers on here regarding an idea I've had......

 

Concrete is a pretty solid material, and when used as a sea defence is prone to the force of the waves and the scrubbing effect of the water and anything solid within the water. Spraying a resin over the outside face of the concrete, and injecting resin at intervals along the length of a sea wall, will give it some added semi-flexible protection from those things. The internal resin will allow the concrete an amount of flex to absorb the power of the waves instead of just reflecting them, and the external resin would prevent the scrubbing of the concrete that weakens it. Topping up the resin coat would be easier than maintaining concrete, and the resin coating would fill any cracks therefore continually adding to the structural integrity of the wall.

 

I've touched on something similar in the past, using a polymer to prevent water ingress through a porous wall and this worked very well, a coat of 20 microns thickness lasted over 3 years when exposed to mid-European weather on a test building.

 

Mark

The wall at Dawlish is of an old design, a modern sea wall would probably not be constructed in such a manner. I don't know the particulars of the Dawlish wall but it looks to be vertical without any piles, vertical walls allow clapotic waves (which move vertically rather than horizontally) to form and cause heavy erosion at the base of the wall. These waves allow the wall to be undermined and collapse. 

Modern sea walls are curved with protection at the base, this prevents the wall being undermined and better distributes the forces of wave impact; it also prevents overtopping (water going over and beyond). The ideal solution would be to replace the sea wall with modern design. Failing that, I think having a steel reinforced slab concrete track bed supported on piles behind the existing wall would mean even if the wall was breached the track would remain in place and repairs would be much quicker and cheaper.

I know more about quays than sea walls but I've picked up a bit working in a marine engineering design office.

Cheers,

Jack

A nice little media snippet further along the coast at Plymouth... According to Radio Plymouth 106.7, the owner of the Wet Wok Chinese Restaurant will be offering a 20% discount to anyone who doesn't take the mickey out of the name when the restaurant reopens after repairs...

 

wetwok.jpg

ewsjo and I ate there when visiting the Plymouth show with Embankment Road (Baby Laira)! Very good Chinese!

Cheers,

Jack

I think that will take at least 2 or 3 months to repair. It's not just the railway, it's the structures around it which will also need stabilizing at the very least before the repairs to the railway even begin. Not to mention there will probably be a big debate as to how they will repair the damage. Will they get the railway open ASAP in manner that means it's likely to fail again this year or next, or will they do the job properly to ensure that section, at least, will last for a couple of decades? Not to mention many companies both rail and otherwise will have to work together on this, the more people involved the longer the affair is drawn out.

If it was done properly I'd imagine a steel reinforced concrete slab for the trackbed, with steel reinforced concrete piles extending down to a good depth. With this setup, even with a complete washout of the surrounding ground, the track would remain in situ and easy to quickly backfill to get it operational again.

What a nightmare scenario!

Best Regards,

Jack

Funny you should mention the decals breaking, I had the exact same problem when doing my Clay Tiger! It looks good nevertheless and I'm sure a small clay spillage could conveniently end up on the darker overlaps!

Cheers,

Jack

I cut corrugated/ribbed plasticard this evening so I thought I'd report back on how the printer handled it. I used Evergreen 4525 which is .040" (1mm) thick and has the most narrow spacing between the ribs (0.75mm/0.30") of all the Evergreen sheets. The ribs make up about 0.2mm of the total 1mm.

The initial problem with the Evergreen sheets is that they are narrow (153mm wide), they will go between the rollers even on my little Portrait! So I had to stick some scraps of plasticard onto the cutting mat to give the rollers something to hold. The next problem is the length, because it's too narrow for the rollers, without scraps of plasticard to extend the support the rollers will fall of the end of the plasticard! I had to leave a bigger cut free margin at one end, then feed it in the other way around to cut at that end (it was easier than cutting up plasticard purely for support).

I set the cutter to 33 thick, the slowest speed, double cut and had the blade at 10.

The cutter didn't seem to have much trouble dealing with the ribbing and the cuts were smooth, even through the curves, though not quite as smooth as plain plasticard. You could hear a slight shudder as the cutter cut across the "grain" but apart from that it seemed to be little different from cutting the usual plasticard. I was worried that the ribs would lead the blade astray, but this didn't seem to happen.

As I wanted to represent corrugated iron sheeting I decided to engrave the shape of the panels. Without ejecting the cutting mat, I adjusted the blade depth to 8 and ran the cutter again to cut the lines into the plastic.

The small triangle truss was cut just to see how the cutter would handle the fine lines. The actual cutting wasn't bad, but it was tricky with the knife to extract the pieces. The outside frame is 0.75mm thick and the webs are 0.5mm thick.

Cheers,

Jack

Can I just say a massive thank you! The information in this thread is spot on and has served as a perfect quick start guide for me.

I received my Silhouette Portrait cutter a couple of days ago and I made my first cuts this evening. I am using Solid Edge as I have been using it at work over the last 18 months so I already had a few digital models made with the intention of printing templates and cutting them out by hand. It has been so simple to export DXFs from Solid Edge and then import them into Silhouette Studio. I didn't have to do anything to the drawings once imported, they were ready to cut and only required the settings inputing before I was ready to hit the "Cut" button.

Thanks for saving me a lot of time in experimenting and troubleshooting as reading this thread has been brilliantly helpful!

Cheers,

Jack

Dapol are on to a winner, because the reality is that their product looks better than the previous Farish one. They effectively have the N scale Class 56 monopoly, so 95% of people who want a grid will buy the Dapol one because it's effectively the only option. When that's the case, you can afford to be lax with regards to how prototypically correct it is, so long as it is sufficiently better than the previous offering, it will sell; the money saved on research, CAD time and Tooling ultimately translates to a better profit margin. Having recently worked for a small firm (not model railways) where I was often party to such discussions, that's all too frequently the attitude that comes across, but from a business perspective it works. At the end of the day it supports Dapol as a firm and keeps them in business to create gems like the Class 22.

With regards to the roof shape, the cab types and strange choices of prototypes for the tooling, I agree with what has been said above by Mike, Jo and others.

Cheers,

Jack

Looks very nice, the motive power looks better in the 60s as do the cars! I agree about the wheels on the Western, the holes look (and are) far too big, I barely notice them on the real thing especially if clean, so in N they should be barely discernible on the model.

Cheers,

Jack.

I think it'll look more pleasing to the eye with a consistent height, plus from a rail engineering point of view it sounds like it's prototypical.

Cheers,

Jack

I second Graham's opinion on the 150/FL66 shot, it's a nice angle!

If you retain the 3rd rail, you could still run a LM Desiro on it as don't the 350/1s have 3rd rail shoes too?

Cheers,

Jack

The weathering on the gray TDA especially is spot on!

The TTA looks much better than a standard Bachmann job; will look perfect in the back road of Baby Laira!

Cheers,

Jack

5) Scotty Dog liveried Cl 37 working service train out of Weymouth. Have photo somewhere. It was the evening loco-hauled train back to Westbury for stabling. Would have worked the Westbury - Wey - Bristol - Wey diagram earlier in the day.

Was it 37408 "Loch Rannoch" by any chance? I have seen pictures of 408 at Weymouth in the late 80s, working Cardiff - Weymouths in 89 I think?

I would say not enough tractors, but that would be pointless, because even an infinite number of tractors still wouldn't be enough tractors!

I know should know having spent several hours operating it, but where's the long grass at the front right of the layout from? It looks especially good in the low down shots!

Cheers,

Jack

Very nice! You've put the TDA 3D model I knocked up to good use! Just need a 1:148 Westerleigh to go with it now!

Cheers,

Jack