coombe glen garden railway

CGGR

Construction and development of the railway

This will follow the chronological planning and building of the railway to date

An early appraisal of the site

Fortunately whilst negotiating the purchase of the house, the owner gave me permission to photograph the garden, and take a few crucial measurements. The pics below show the state of play.

 

This pic shows the large decking area on the left, which could make a useful area for a good sized terminal station. The very thick retaining walls look as though they might need some serious muscle to alter/demolish them! There is a second shed immediately behind the one seen, but 18" higher up. Both are on very substantial concrete bases - 18" thick!

Another view from the bottom of the garden, showing that the levels on the R and L sides of the garden do not match up. There were 2 dead apple trees in the RH bed, and a beech hedge running right the way down the far side (a problem with leaves on the line in autumn? - well probably not, beech doesn't shed it's leaves until spring, when the new buds start to open)

some initial ideas

I decided that I could plan more comfortably with the two sheds removed to the bottom of the garden, well out of the way of any railway. Their removal was a saga in itself, but not relevant to the railway story.

This left two very substantial (and thick) concrete bases. A little experimenting with a couple of sledgehammers soon decided that it was impracticable to break them up by hand, so they would have to be planned into any railway. Fortunately they were both reasonably level and flat.

So this left 3 fixed reasonably level areas for a potential use:

(a) the decking which measured approx 20' x 9'  and was at the lowest level

(b) the lower shed base which was approx 8' x 6' and 15"  higher than the decking and

(c) the upper shed base of a similar size, but a further 15" higher again.

The decking would be ideal in the long term for a terminal station, but could probably be used in the short term for one end of a 'dog-bone'

The middle area could probably be developed as a village with a halt, or for some industrial use - say a mine or a quarry, with a through line running between the two shed bases - which fortunately had a small gap between them - otherwise we may have had to hire in a pneumatic drill!

If the top area was extended across the full width of the garden, it should be possible to at least construct the other end of the dog-bone. Doing this though, would mean moving the existing top few steps , and relocating them in the corner - with a tunnel underneath on a curve!

Now I would have to work out how to drop the 3' from the top level to the decking whilst still keeping the gradients to no more than 1 in 50, and the curves as wide as possible.

Here is a rough idea of what I did:

You will see that in fact the new steps had to go over 2 tunnels, so the slabs had to be made removable for access. This involved the making of a very sustantial timber frame over the tunnels.

 

It proved possible to create a level area opposite the decking to construct an intermediate station, with a passing loop, and also very importantly, a 'steam-up area' at waist height - a must for us more senior enthusiasts! This stage of construction involved several months of heavy landscaping, including demolition of very thick concrete walls, moving large amounts of heavy clay soil and building many new walls. Tribute must be paid to my eldest grandson Mike, who was in his middle teens at that time, and did much of the backbreaking work.

Some pics of this early construction can be found below:

 

This is an overall view, with the new steps partly constructed, and the track just roughly laid out to check the levels. The newly built retaining wall (pinkish bricks) for the lowest level can be clearly seen. The lower curve under the steps is very tight - about 30" radius, but was made exactly level to facilitate running with especially live steam. The bottom part of the dog-bone has yet to be finished.

 

A cruel close up of one of the partly finished new walls, and the temporary track laid across what will eventually become a proper tunnel. Most of the track foundations are 'Rowland's mix' (a weak cement with added peat). A good layer of ballast will be added later.

 

In a few places, such as here where the intermediate station will be, old paving slabs have been used. The steam-up area is the 2 tracks in the immediate foreground. The timber viaduct is only meant to be temporary (but much of it is still in use today!) Use of part of the old massive retaining concrete wall has been made here. I lowered it too much! - so had to put a course of bricks in to raise it back up a bit  - the gradient up the timber viaduct was too steep (it is also on a very large radius curve - about 6'-8' radius - very generous in 16mm scale)

The early beginnings of the ironstone mine - on the old lower shed base - the edge of the old upper shed base can be clearly seen on the right, with the newly completed flower bed wall on top. The box hedge has also been recently planted, and by 2011 completed filled in this area, and is kept clipped level with the top of the wall. The dreadful plastic edging has now been replaced by wooden fencing. The girder bridge is from the previous garden railway, and is constructed from L-section hard plastic girders (courtesy of B&Q) The 'main line' in the centre is now completely overrun with 'mind-your-own-business' - but it looks splendid (and natural).

The first temporary loop laid to enable trains to return to the top level. Note the use of anything suitable - bricks, bits of wood etc.. to get the gradient by the fence correct. In fact this gradient is very slight - between about 1 in 80 and 1 in 100 - no problem for live steamers.

This pic shows some second thoughts about the return loop, and how it might link to a terminus. The felted (grey) area is where the terminus will be, with some temporary track in place.

 This pic shows the method of construction of the (temporary!) curved timber viaduct, and also the very generous curve - necessary, as the viaduct is on a rising gradient. The drain pipes have holes drilled through and a section of steel inserted, which rests on stones. By changing the position of the insert the pipe can be raised or lowered slightly.

The decking is sections of old fence panel - creosoted and also well weathered.

Pointwork is in place ready to construct a passing loop in the foreground.

This pic gives an overall view of the final version of the initial plan utilising the 'dog-bone' design, with all the track bases made, but track only temporarily laid. An extra chord has been added on the far left to give a useful triangle, which allows a small continuous run at the top of the railway - very useful for tesing purposes.

Further deveopments

Whilst completing the initial plans above - putting in proper bases for the track, ballasting, putting in platforms etc.. other ideas began to firm up - in particular that it might be possible to make a complete circuit for continuous running, with not too severe gradients. The downside was that a huge high embankment (over 2' high) would have to be constructed all the way around the edge of the decking, with a bridge or viaduct over the large pond at the bottom of the garden opposite the lower part of the decking. This pond was put in before any of the railway was started, but fortunately I had salvaged the very long girder bridge from my previous garden railway (9' long!), and this was just long enough to span the pond - though how to fix it was another matter. In the event I used round plastic pipes driven into the ground at either end of the pond. These had tight fitting T-shaped wood inserts, on which rested the ends of the bridge. A temporary curved wooden viaduct was then constructed to bring the railway round and up under the long beech hedge, in similar fashion to the one mentioned earlier.

This view shows all the above features in place. A second smaller girder bridge was later built - in the same style - to span the path under the rather attractive arch, which was custom built for the space available. The cast in situ and self coloured (cement pigment - not paint) station platforms can also be seen either side of the central path.

 Before completing the embankment, a further modification made, which was to not have an embankment for the whole length of the decking, but rather to make an attractive timber bridge on stone piers, as can be seen above. This has the further advantage of being able to see the trains passing along the line at the back. The pic also shows the early stages of constructing the 'zoo'. Much use was made of 'Astroturf' here and elsewhere. The area under the bridge is earmarked as the zoo car park. Buildings are also beginning to appear. The embankments are all concrete on a wire mesh frame, with a final coating of 'Rowland's mix' which will encourage moss etc.. to grow won it.

extension of the railway down to the lake

My youngest grandson had become very interested in the trains and I had already built a few cheap wagons and 2 battery locos for him to play with, but what was needed was a section he could more or less call his own. Checking levels, it was just possible to put a spur off the bottom part of the 'dog-bone' to pass through both sheds and continue to a small terminus along the edge of the pond. This just had a run round loop - which initially was very small, but thanks to some of my more adventerous friends, who wanted to run their live steamers down there! I had to extend the length of the run round. The only way this was possible, was to move the approach point back about 15"/18" This meant making a curved point, as the approach was on (a quite sharp) curve. 

This had a further advantage of also being able to install several sidings in the sheds for storage of stock (all valuable stock and all locos are kept locked in the house) The only drawback was that the gradient from the shed up to the rest of the system was very steep  - probably around 1 in 30, but as only small locos and short trains could be accomodated this in reality was not really a problem.

 This pic was taken at a members 'Open Day' before the loop was extended - a little 'hand-shunting' of the wagons was necessary to return the train to the main part of the railway. It also shows the small beach - complete with beach huts and rowing boat. Unfortunately we had been in a dry spell and the water level in the pond was quite low and did not reach the beach.

and so things progress.....

 A canal has been built in the gap between the lower shed base and the end of the decking, with a dummy tunnel at each end. A plastic liner was used, and concreted in, it has holes at either end to prevent it overfilling and flooding the decking. A narrow boat was built and the goods yard constructed. The goods shed is a modified 'Modeltown' engine shed!

Another small area being developed - the exit from the station yard. The red girder bridge is built from 'plasticard'

 

 Work on the ironstone mine has begun.

 

Roads, fencing a level crossing and more buildings have all been added, together with some more small box bushes for miniature trees. The fence posts are lengths of old Tenmille rail drilled in a jig.

 more plants, buildings, accesories and characters - which all help create 'atmosphere'

development of the highest part of the railway

To date little more had been done to this part of the railway - except to rename the station from 'Ross-on-sea' to 'Uphill' Situated at the very highest point, what else could it be called!

Firstly, new platforms were constructed - my usual method - except I had run out of cement pigment, and foolishly painted them with cement paint - which soon started rubbing off!

Then a very smart new station building was constructed (thank-you 'Modeltown') with just a simple shelter for the opposite side. The track did not need to be altered, as it was put in from the start with a passing loop. Finally a decrepit rusty corrugated iron engine shed was built together with a fine water tower and coaling crane (all 'M.T.' again)

 

The other development at the top, was to install a standard gauge line and a small 'GWR' style 'Pagoda' Halt on the area immediately above the narrow gauge station.

 The 'Pagoda' was constructed from corrugated 'plasticard' and the platform from surplus standard gauge sleepers. The (working) lower quadrant signal is a GRS kit. The rail and chairs are from the G3 society, and the ballast is my usual horticultural grit. The low relief buildings came from my previous garden railway.

 A view showing the relationship between the standard and narrow gauge lines. The standard gauge tunnel is a dummy only 10" deep, but is painted black inside to increase the illusion.

things never stand still

Over the last few years, we have begun to have much more trouble with foxes causing damage - they have been digging up much of the garden, damaging buildings, as well as leaving faeces around the garden. It has proved impossible to keep them out. After we blocked up all the holes, they simply started jumping over the fences. When I started the railway mange was rife, and there were very few around, but now numbers have increased dramatically.

The area suffering greatest damage was around the pond - 'Lakeside station and surrounds in particular' So the decision was reluctantly made to dismantle this bottom section. This has not affected my grandson too much as he is old enough now to run anything - except of course my 2 live steamers - and he is allowed to use all the railway now.

Another change made was to change the track layout to allow 'figure of eight' running. This is in addition to the original 'dog-bone' and later complete circle - both of which allow continuous running. To do this ment some wholesale changes to the 'Coombe Junction' area, as well as further down that section of track, and creation of a new triangle on the opposite side of the garden near bridge halt

construction of a new south chord at Bridge Halt junction in Spring 2012

The purpose of this was to make a new triangle, to add additional operating interest for visitors - or was it really to 'confuse' them even more?

The construction followed my usual techniques, which may be of interest to some - so here they are, with a few pics.

Some old redundant (Peco) points were reused and the new curve laid out roughly on some old pieces of wardrobe, so that the wood could be marked up and cut to shape and size with a jig-saw (coarse blade was used). This was then screwed into the existing wooden frame, and a couple of supporting legs added (I prefer 'treated' rough sawn timber where possible) The surface of the timber was then completely covered in roofing felt.

Next the track was properly laid, and the 'cant' adjusted where necessary - most of my curves are canted slightly - with small packing pieces of 'plasticard', then the track was pinned down. At this point a battery loco was run in all directions through the curve and the points - all was well.

Construction of the frame for the embankment followed - this is fairly clear from the pic.

No special techniques are needed. Then fine mesh chicken wire is fastened over the wooden frame - as my heavy duty staple gun had broken, I simply tied it in with garden wire - again see the pic.

 

Newspaper sheets - 2 thick - were placed over the mesh, then a thin strong (i.e. less sand)mix of cement was spread over the top. When well set, a final coat of 'Rowlands mix' was put on. If adding a second layer of cement, I always add some builders PVA to the mix to aid adhesion.

 

track plan 2012

If you look closely at the plan, you will see that there is also a small continuous run possible at the very top of the garden (very bottom of the plan!) in addition to the others previously mentioned. This is especially useful for a quick test of locos or stock - as it has some gradients and sharpish curves.

As mentioned the bottom pond section through the sheds is now removed, and currently the ironstone quarry is under redevelopment, as at Autumn 2012. This work will not be complete until later in 2013 - sadly, no further work was possible due to a recently diagnosed progressive brain disease, and the railway was dismantled in stages after one final members and friends Open day in early Summer 2013. Dismantling started the following day from the bottom upwards, leaving the final upper circuit in place until Autumn 2013