Brick arch viaduct Blackgang

AllWight · Apr 07 2011 18:37

As some of you will be aware I am in the thows of extending Blackgang. There are three modules being built by Keith Smith, Roger Salisbury and Tony Holland. The fourth will be built by me and will be curved section with the intention to take the layout through 90 degrees and in the modular fashion so as to be flexible for exhibition organisers. It will consist of four boards with either a 4 or 5 arch viaduct and simple scenery rolling down to a stream or the Chine (another name for a narrow gorge). The boards will be much slimmer in depth front to back and the track will be down to 8' radii.The height of the viaduct will be around 18", any deeper would make it difficult to transport with regard for space.

AllWight · Oct 11 2011 18:16

I have finally done it and bought the timber for the curve section of blackgang. the 8' radius curve will be on a viaduct with approx 14" drop from track bed to base board. The viaduct will include 6 - 8 arches depending on the development. There will be a small road and a river/stream from the chine to give extra added interest.

As the boards develop i will update

Mark

MEL 41 · Oct 11 2011 21:57

Really looking forward to that Mark.

AllWight · Oct 11 2011 22:10

Thanks, I had to dust off the woodwork tools and buy a new jigsaw as the £150.00 one that I was assured would last has fallen apart internally. So I decided to buy a cheap one and if it only does this job, then so be it. Knowing my luck the cheaper one will out last the expensive counterpart. Such is life.

I am still undecided on the number of arches it will be at least 6, maybe 7 or 8 depends how much of a sadist I want to be. I have the track and I am starting on the signals.

Mark

AllWight · Oct 27 2011 17:27

Hi Chaps

The first curved board of Blackgang Viaduct has been made in a basic wooden frame. It will eventually consist of six arches with a scale 20' drop or 11" in actual terms. It will be modelled on an 8' radius and take the layout through 90 degrees. I have a little request to any people out there. I need some white expanded polystryene for the land form so if you have any big block of it that you wish to get rid of please let me know.
As soon as I can get some pictures I will forward them onto the forum and for the magazine.

Mark

MEL 41 · Oct 27 2011 20:51

Have you got a local electrical retailer or DIY store - Currys, Comet, B&Q etc. - Mark? I've found that they're often glad to get rid of polystyrene if you ask nicely?

AllWight · Oct 28 2011 19:02

Right

Board 2 is made and ready to have the track bed placed on. The first board has been worked on as well today. The first three arch liners have been made from thin modelling ply. The outer skins of the walls of the viaducts have been carefully cut out and glued on with a slightly thicker modelling ply. Now waiting for the glue to go off.
As soon as the camera has charged up i will take a few piccies and circulate them. Ihave placed a GWR B Set coach on the deck of the viaduct and it looks pretty convincing.

Mark

AllWight · Nov 11 2011 19:43

Hi time for a quick update.

Boards 3 and 4 are now made and I am now starting on the arches on board 3. I have been gradually acquiring some polystyrene for the landform but i am not quite at that stage as yet. I have also designed the legs and made the legs for the middle pair of boards.

Will keep you posted as things progress

Mark

AllWight · Nov 16 2011 15:01

Yet another update!!

Right all four boards are now up together with the legs and at the correct height to match up to the existing layout. The modelling plywood that I initially used on the viaduct started to warp and go like waves of the sea, so it has been stripped back. I will instead use some 6mm ply which will be far better and a lot stronger. It will still be six arches at a length of about 4'. There is of course an approach into and out of the viaduct as well.

I still have a need for the white expanded polystyrene for the scenery land form so if any one out there locally in the Hampshire/Surrey/Berkshire/W Sussex areas has some they want to get rid of then please let me know. Preferably the sheets of polystyrene and not the moulded stuff as used for packaging the new TV.

Cheers Mark

AllWight · Nov 21 2011 16:12

Hi Chaps

I have now re-done the first section of the viaduct (board 2) with a sheet of 4mm ply and it holds its shape, unlike the modelling ply. For the underside of the arches I have used 30thou plastic card and glued it in place. As the inner arch and the outer arch are slightly differing sizes due to the curvature of the viaduct itself it seemed logical to use a flexible and pliable material for the arches. The gap between pillars on the inner side of the viaduct is 6" where as it is 6 1/4" on the outer side.

Board 1, 2 and 4 are ready to have the track offered to it but this will have to wait till I get board 3 upto the same specification as board 2. I also intend to put a super elevation to the track as well to improve the running across this section of the layout. I will try to have the track down in time for the Winter GTG on December 4th at 8th Alton Scout Hut.

Mark

AllWight · Nov 27 2011 21:32

Right the basic shape of the 6 arch viaduct is complete. The track is now slowly going down and it will be super elevated as well. The brick card will go on as soon as I buy some.
There is going to be a small stream under arch 3 and a roadway under arch 4 being the middle pair of arches. The others are part of the scenery and the landform that rolls down to the lower levels.
It will be on display at the winter GTG at Alton on Sunday 4th December for any one who wishes to see it for themselves.

Mark

AllWight · Nov 28 2011 21:26

I have started to put in the polystyrene and run out still need lots more. Anyone who is coming to the winter GTG that has any polystyrene block that you do not require please bring it along it will be much appreciated.

Cheers Mark

AllWight · Nov 29 2011 22:31

Right whilst I am waiting for a friend to deliver some polystyrene I have now completed the track laying across all four of the curved boards and it looks pretty good if I do say so myself. Just have a few tweaks here and there but otherwise it all looks good. We shall be using it on Sunday for the Winter GTG. The formation will be 20' (5 of the 6 scenic boards of Blackgang), the curved section, 12' of Chale, the last scenic board of Blackgang (4') and the 8' of fiddle yard. It will fit and it will be snug but I like a challenge.

See you there chaps

Mark

AllWight · Jan 20 2012 16:12

Time for an update

The polystyrene is glued and carved to shape and the facia boards are gloss black. I will be applying the plaster of paris bandage shortly to give the scenery strength before the brown emulsion and final top surface of the grass/flock material. I may well be doing a scenery demonstration at the Alton Show on 4th and 5th of February at Eggars School. Come along and see Blackgang in its biggest form yet.

Cheers Mark

AllWight · Jan 24 2012 18:07

Me Again

Right I have covered the polystyrene (and me) in plaster of Paris Bandage and brown emulsioned 3 of the 4 boards. I will be off to the model shop tomorrow to get the last bit of bandage to complete board 4.
The viaduct is also in brown emulsion as a short solution to get rid of the plywood look. I might have it finished in time depends what else happens along the way.

Mark

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