Garden Railway Forum

Brilliant Phillip, It’s going to be a winner for sure.

By the way, what pump are you going to be using…

FWLR wrote: ↑Tue Oct 16, 2018 10:37 am By the way, what pump are you going to be using…

Rod,
Sorry only just realised you asked a question.
It's a Blagdon 'Force Hybrid 5000'

Thanks Philip…It’s got some great reviews….

Some small progress. A few days go I managed to check and adjust the stream bed levels so today I took advantage of the nice weather to lay a temporary polythene liner and run the pump just to see it all working. As you'll see I need to adjust the top end to give myself a little more headroom, but other than that it all seems satisfactory. The plan is to remove the polythene and use it as an approximate template for the real liner, it should be a lot easier to cut it flat on the lawn rather than draped around the plants.

BTW, the bells at the beginning are not the opening of The Hunchback of Notre Dame, just that SWMBO has some wind chimes hanging there which kept catching my head!

Nice one Philip, that works well. I like the sound effects too, both the gurgling water and the bells.
Grant.

Excellent job there Phillip. It’s sounds just right too.

Would you need to put some kind of a grill in the system so has to keep bits of rubbish flowing out of the Manifold.

Looking good, Philip. That manifold works a treat!

Rik

Nicely done Philip.
You're tempting me to rethink the blue slate simulated River Greta!

I can already hear the trickle of water with the exhaust beat of a loco already, lovely.

Thanks chaps.
I bit the bullet and ordered a larger dustbin/sump last night. The 50 litre one is full to the brim when the pump is off and it all runs back, and the pump tends to gurgle when its running because there is only just enough of a reservoir. It was Ok when I first did it, but then of course I decided to extend it by about 4ft....!

Rod, the pump normally sits in a filter housing which I've removed atmn, but will be refitted when it's all finished. That leaf actually got sucked in when the water line syphoned back and then got ejected again when I switched back on.

Phil, It's easy for me to say, but from the pictures of your line, it doesn't look as though it would be too much of a job to convert.

Great work Phil. You set me thinking again about the possibilities for my Charnwood Forest line. It may be the thing that kicks me into any sort of action! Between you and Rik I really do fancy the idea. I'd never considered the problem of the volume of water in the system and the need to have the capacity to hold it all in one place when the system isn't running.

THat's one of the greatest things about this forum, the things that you may not have considered will almost certainly have been pondered by someone else - and it's all freely shared.

Now, let me see where I could weave a stream into the garden...................

All the best,

Andrew

Soar Valley Light wrote: ↑Sun Nov 04, 2018 6:19 pm I'd never considered the problem of the volume of water in the system and the need to have the capacity to hold it all in one place when the system isn't running.

It did catch me somewhat by surprise when it really shouldn't have done! The thought had crossed my mind some while ago, but 50 litres seemed like an awful lot of water just thinking about it, and I took it no further.
Calculating the capacity of the static supply pipe is relatively simple, but calculating the volume held in the flowing stream is at best an educated guess. Then it needs to add the volume necessary to still cover the pump to at least it's minimum depth when the rest of the system is full. Then plus some extra capacity for leakage etc. Finally, I have the problem of this thick heavy clay and the difficulty of fitting a big hole between existing tree and shrubbery roots, all of which encouraged me to keep the bin no bigger than it had to be. As I said, the early test seemed to be Ok, but adding an extra 4ft of stream made an apparently huge difference.

Hi Phillip, it did look funny when the leaf popped out of the manifold. Didn’t think you would run without a filter.
The extra run you have put in does make the stream a lot more scenic though Phillip.
If I had the room, there would be one on our line also. Anne loves to see running water, especially over rocks like a waterfall.

Soar Valley Light wrote: ↑Sun Nov 04, 2018 6:19 pm
That's one of the greatest things about this forum, the things that you may not have considered will almost certainly have been pondered by someone else - and it's all freely shared.

Now, let me see where I could weave a stream into the garden...................

All the best,

Andrew

Couldn’t agree more with Andrew’s comment. And the last sentence also………

philipy wrote: ↑Sun Nov 04, 2018 8:08 pm
Calculating the capacity of the static supply pipe is relatively simple, but calculating the volume held in the flowing stream is at best an educated guess.

A 'rough and ready' formula from my days in the Fire Service, when trying to work our how much water a lake or pond held was surface area in metres squared, multiplied by 2/3 average depth in metres, multiplied by 1000 for total litres available (and yes, the fire service was completely metric even in the late '70's!)

Of course, you'd have to scale it down a bit!

Well, I ve been a busy bunny for the last couple of weeks. Having got the basics of the stream sorted I decided it was time to get serious about the railway bridge over it. My initial thoughts were to make a mould and pour it in solid concrete, in situ. As I've posted before, I have previously made a bridge support using a plywood mould with the mortar courses applied to the inside with hot melt glue, but that was a simple slightly tapered box. This bridge is much more complicated, being on a skew for starters, plus needing the arch of course, plus I really wanted to cast the parapets as an integral part, plus I would need to cast it with the stream liner already in place. I started by making a kind of 3D template out of some foamboard, on the basis that its easy to cut and I could replace bits if the geometry came out wrong. It wasn't as bad as I feared so started to apply the mortar courses as well, thinking that perhaps I could reinforce it and actually use it as the mould itself rather than using ply.

At this point Greg was posting his Bridges of The Sandstone & Termite, thread, with a link to his web page on using Hebel blocks. I had seen this before but forgotten about it but the picture of his huge viaduct got me thinking. Why couldn't I carve a bridge from Thermalite blocks ( the UK version of Hebel)? It also jogged my memory that Rik used similar methods for Beeston Castle. So last weekend I made a trip to Wickes and bought a couple of blocks for a whole £1-60 each! They aren't actually Thermalite, Wickes sell them as "Aerated blocks" but they seem to be much the same. Although in theory 200mm thick Thermalite/Celcon blocks are available, as far as I can see you have to order a pallet load, individual blocks are only easily available in the 100mm thick version so I needed two and would have to 'glue' them together. They have rather rough faces which are bit difficult to smooth but I got rid of most of the roughness by laying the two blocks together and simply rotating one on the other like a pair of millstones. The one on the left is smoothed and the RH one is as they come.

I made a template for the shape of the arch which was copied onto one face. Then the two blocks were clamped rough sides togther and angled parallel lines drawn across the bottom to match the angle cut through the track base. The template was then used again to mark the opposite arch. Finally the two blocks were separated and the template used again to draw arches on the inner faces. I then used an old panel saw to cut the vertical faces of the arches and a masonry bit in an electric drill to chain drill the curves. The curves were then approximately smoothed to the required shape, although final shaping would have to wait until the two halves were fixed together.
Next I used the saw again to cut out the track bed from the top of each block, leaving a side piece sticking up to become the parapet wall in due course.


To fix the two pieces together I used Stixall, as recommended by Phil ( Lonsdaler) and it seems to have worked well. To hide the join on the inside of the arch, I made up a slurry of waterproof PVA with some of the sawn block dust, and used it as a grout. It dries slightly darker but is approximately the right colour - a grey line can just be made out in the picture below.
Next I cut the spare out of the blocks at each end by sawing down parallet to the arch sides and then sawing horizontally to meet them. This allows the bridge to drop into the hole in the trackbed with ( hopefully) enough play to allow for the stream liner and underlay.
I then cut the parapets down to the right height and had a minor disaster, one of the overhanging parapet ends broke off. It turned out that there was an internal airhole right at the junction with the main block which made it very weak. I tried using Stixall to glue it back together, and although it did stick, it left the joint rubbery and flexible, so I made another slurry, this time using SBR and block dust, and grouted the gaps all round. Again there is a darker shade but I think it will be ok once everything is finished.
At this point I started scribing the blockwork onto the faces.


The off-cuts from the top of the parapet walls were using to form coping stones which were glued on by liberally damping both faces and then painting with SBR. Once rigid I again grouted the gaps with SBR and dust.
The join in the broken parapet can be seen as a pale grey diagonal line towards the LH end of the rear parapet
In this picture I had started colouring one face before I remembered to take a photo!


This is the bridge with a first thin coat of Everbuild mortar colour (Buff plus a touch of Brown). It actually looks better, less blotchy, in reality than the photo, but I'm wary of putting on too much colour since I'm trying to get close to a pale Cotswold colour. I can always go over it with more, but I can't take it off!


Finally I took it outside and placed it loosely into position to get a feel for the eventual look - clearly it does need more colour, but I'm very wary of it going too yellow, like the top shows, and adding a little more brown tends to make it go a reddish shade.

That's looking raight grand already!

Peter in Va

It would never have occurred to me to carve a bridge from aerated block but that looks very effective. I know it'll weather even more naturally, but it's already looking the part. Brilliant.

That really, looks the part, love the skew design too... If you build the colour up gradually I reckon you'll get it spot on. It might be a candidate for the "only in natural light" rule I apply when I'm weathering rolling stock etc, I find it very hard to judge colour accurately in artificial light...

Cheers,

Andrew.

Very nice.