This isn't only "How" ..... , it's also "Why" I extended the sand quarry siding.
The siding has been in operation quite successfully for about four years now (see Progress Report 77) but it has always been a little short. It would happily accommodate eight hopper wagon plus brake van or nine hopper wagons without the brake van, but there wasn't enough room for them plus the loco. The difficulty was that there was very little room for expansion.
As you can see from this plan, the quarry was tucked away in the corner of the lawn close to Bickerton.
So, I had three alternatives:- Abandon this site and place it elsewhere on the system
- Extend the siding by creating a tunnel into the rock face
- Turn the siding through 90 degrees to run alongside the track as it descended from Beeston Castle to Peckforton
The most promising seemed to be the third option which, I decided, could also offer me the opportunity to create a link between it and the mainline before Peckforton
This would involve losing a small portion of the lawn, but the advantages it offered seemed worthwhile. Not only would it lengthen the siding, it would:
- provide a hypothetical link from the mainline to Peckforton Castle just outside Peckforton
- provide an additional reverse loop to increase operational potential when visitors used the line
The first task was to mark out the intended route of the new retaining wall. For this, I used concrete 'breeze' blocks. This was partly for convenience but also because I wasn't sure it I would have enough larger sandstone blocks in store for the purpose.
A trench for the footings was then dug along the line of the planned retaining wall, approximately six inches deep.
An approximate three inch layer of crushed stone and rubble was laid into the bottom of the trench. This was mostly created from stones which were dug up in the garden and also from chunks of concrete rescued from abandoned projects on other parts of the line.
The next stage was to fill the rest of the trench with concrete - a 3:1 mix of sand and gravel to cement - for more information on mixing concrete see How I created cast concrete platforms
Before creating the retaining walls, I needed to work out how tall they needed to be. This, in turn, would have to be dictated by the height at which the trackbed needed to be along the length of the extension. To determine this, wooden stakes were cut from a length of 1"x1" batten.
Starting at the far end of the extension, where the track would be joining the main line just outside Peckforton, I drove one of the stakes into the line of the intended trackbed until it was level with the mainline - using a long spirit level to check.
This process was repeated from one stake to the next along the line of the trackbed .......
........ until the existing siding was reached.
It turned out that the trackbed of the siding was only about an inch lower than the mainline trackbed - which meant that there would be hardly any gradient needed over the length of the extension.
Using the stakes as a guide, I then selected chunks of sandstone from my 'one day they will come in useful' pile and bedded them down into the partially set concrete.
After another couple of days, to allow the mortar to harden off, the now raised bed was filled with soil from another part of the garden (from where I was laying paving slabs) and then concrete breeze blocks were laid down along the line of the trackbed.
A further couple of days later, tracklaying began, starting with the junctions between the existing track at each end. At the sand quarry end, the concrete ballasting needed to be chipped away with hammer and chisel to allow the buffer stop to be removed and also to allow the track at end of the old siding to begin the transition curve on to the new trackbed.
The new track could then be joined to the old siding and extended along the new alignment.
My tried and tested method of fixing the track in place was to drill a hole in the breeze block to take a plastic rawlplug and then screw through the sleeper.
A new LGB R3 point was put into the existing track on the approach to Peckforton station
.... and the track at that end of the extension laid.
The rest of the track was then laid - you can see the position of the fixing screws in this shot along the right hand track in the loop. I never screw points down - they are allowed to float as I have found that screwing them down can distort their geometry.
The trackwork was then tested with some of my most demanding rolling stock.
The track will remain unballasted for a couple of months to enable me to try it out in a few running sessions. This will allow me to tweak the track should any problems arise. However, so far, so good.
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