Sunday 12 October 2014

Look out, its the copse

Freshwater will have more trees than any previous layout I have built, so I wanted to get some planted in time for the Farnham show (and 2mm Scale Association AGM). Previously I have used plastic tree armatures from Heki and Woodland Scenics. These start off as 2D trees, the branches of which need to be bent to produce a not very realistic 3D tree before attaching bits of foliage.

This time, I wanted to try new techniques. I had purchased a tree-making kit from Ceynix many years ago, and I have collected some old mains leads to source copper wire for soldering together. I would build one tree using each technique and decide which I liked best.

The soldered copper method involves stripping mains cable (multi-core) and then twisting, bending and forming branches. The result is then soldered together, requiring a big iron, clips or pegs, or asbestos fingers. I got as far a the second branch before I gave up.

The Ceynix method uses short lengths of florist's wire (a fine stiff wire with green plastic coating) bundled together and bound with florist's green sticky tape. Branches are formed with two or three wires bound together. Branches are then gradually bundled together until a complete tree is formed. The tree then needs to be coated with air drying clay. This is a long slow process. I used a wooden tea stirrer and a pot of water to aid the procedure. When dry, the tree is painted, a quick spray of grey primer and then thin washes of grey-brown shades. The fine twigs and branches are represented by what is called folinet. This is a fine black jumble of synthetic fibres which has to be teased out before gluing in place. I have been told that this is no longer manufactured, so an alternative solution will have to be found soon. To finish off, a spray of aerosol mounting glue is followed by sprinkling with fine foliage.

I found this method much better, and liked the results, and managed to complete 12 trees in time for the show.

No matter what method is used to make trees, a good book of tree pictures is essential to produce realistic trees. Would anyone build and paint a loco, coach, or even a wagon, just from memory? Getting the general shape, density of branches and colour tones right really brings a tree to life.

The first photo shows a sycamore tree, with the taped bundles of florist's wire formed into branches. The last few millimeters of each branch is a single strand of the florist's wire without tape. The oak tree in the background is the real thing,

 The next photo shows the coating of air drying clay on a couple of smaller trees.

And finally, the small copse of 12 trees planted on the layout. The sycamore is in the centre, with a coppiced silver birch to the left, and several small hazel bushes behind. Below the canopy of the main trees, some small alder saplings (single pieces of florist's wire with foliage added)  are poking up through the ground cover.

 So, 12 trees do not go very far on a rural layout. I will be building trees for many weeks to come.

Friday 22 August 2014

Signal Success for Freshwater

Following general scenic work completed in time for the Basingstoke exhibition, a start has been made on some detailing and buildings. One important detail item is the starting signal. Fortunately there is only the one proper signal on the layout, as it has taken 6 months to build it. The two ground signals required will be another story.

I wanted to build a typical SR rail-built upper quadrant signal, operational of course. I purchased some etched brass signal boards, counterweights, brackets and ladders from MSE. The post would be scratch built, using bullhead rail from the 2mm Scale Association. I laid two longish lengths of rail together, and joined them with a blob of solder at each end. I could then drill through the pair for the joining bolts at the correct intervals, confident that they would line up later when the rails were parted. I found a piece of card of suitable thickness, and cut comb-like teeth into it. With some wire passed through the rail holes at each end, I could then sandwich the two rails either side of the card and solder the joining wires in each hole, with the card keeping the rails the correct distance apart. The comb slots in the card meant the resulting signal post could be slid off the card once complete.

I had some small surface mount gold-white LEDs, and decided to use one as the signal lamp. It is rectangular rather than cylindrical, but is about the right size. I formed a triangular bracket from some unused nickel-silver etch and soldered it to the signal post, and one end of the LED to the top of the bracket. This formed bothan  electrical and a mechanical joint. Some very fine enamelled copper wire was soldered to the topmost terminal of the LED and runs down the post to the lampman's platform. The platform is actually a piece of thin double sided PCB. The lower face is soldered to the post with some more nickel-silver brackets. The top face is insulated from the post, and so the other end of the enamelled copper wire is soldered to it, as is the top end of the ladder. Electrical current for the LED therefore flows up the ladder, through the enamelled copper wire to the LED, and then down the signal post.

I used an old 4mm copper clad sleeper as a base for the signal, with the post passing through a hole drilled in the sleeper, and the lower end of the ladder through two smal holes. Both were soldered to the copper, again for both mechanical and electrical connection, the gap at the centre of the sleeper keeping them electrically separated.

A piece of nickel-silver was added to the top of the post for its cap, and some small backets from the MSE etch soldered to each side of a rail for the signal arm pivot wire to pass through. An MSE counterweight and bracket were made up and attached just below where the signal arm fits.

A pivot wire was soldered to a signal arm from the etch, and the arm and post were painted, sprayed with white primer, and then brush painted black and colour details. Some red and blue-green paint was mixed in some Krystal Klear PVA which was then added to form the spectacle plates in the holes in the signal arm.

The final bit of above ground work was to add the operating wires. This is a very fiddly job, requiring good right-angle bends in the wire and a lot of luck.

Below ground, I created a lever arm from some more PCB, pivoting on a wire pin through the two rails. The lower end of the operating wire passes through a small hole in the PCB. A couple more pins were soldered into holes drilled in the PCB to act as mechanical end stops, so the signal operating wire cannot be pulled or pushed further than required and thus causing damage.

The signal was then carefully glued into a hole in the baseboard, with the base covered with ballast and ground cover. I will probably regret not making it removeable when cleaning the track, but I have not found an unobtrusive detachable mounting method yet.

The final piece of the puzzle was the operating servo. One of the new design, 3D printed, Merg servo mounts was used, with the operating wire bent into a curious form to reach the lever arm below the signal. In the end, the operating movement was not as great as expected, and I could have got away with a smaller lever, but it works.

It is now configured into the Merg CBus system so that a single CBus event will raise the signal arm. This can be generated from a Merg CANCAB controller, or a simple push button on the control box I made to give simpler operation of the uncoupling magnets.

Any of the route setting events will lower the signal arm, so it should not be possible to forget returning the signal to danger before the next movement takes place.

Sunday 22 June 2014

Some buildings for Freshwater

At the Basingstoke show, the only building on the layout was a Ratio SR concrete PW hut. There are only four other major buildings required to complete the layout, but all will need to be scratch built. I started trying to create drawings for the station building, using a 3D drawing package, but the more I did, the more I thought about 3D printing the building instead of using plasticard and printed paper as I had orginally intended. The complex decorative brickwork would be really difficult to reproduce using the traditional building methods, but should be pretty simple for 3D printing. However, the station building is complex and quite large, and would be an expensive experiment if 3D printing was not up to it. I therefore turned my attention to a smaller building - a corrugated iron shed that stood in the goods yard, and is visible in the background of several photos I have collected.

Corrugated iron has always been a challenge for 2mm/ft scale. The best looking solution, aluminium foil corrugated between a pair of suitable rollers, is extremely delicate and easily flattened or distorted. Creating it in 3D is also not straightforward, but I thought I would give it a try. I found details on the Internet about the 'standard' size (or possibly the most standard of the sizes), and an image of a typical profile. The sheet width is pretty standard, but was available in various lengths up to 12 feet. I used the profile image to create a 3D object of a standard sized panel, corrugated on one side, and flat on the other, about 0.7mm thick, so that it would exceed the minimum wall thickness for 3D printing. I then built the shed model by cloning and resizing these panels as required. I varied the panel positions to accentuate the overlaps and joins of the original building, and added doors and eaves to suit. I knew that the window frames would be too small to print, but I found some Ratio etched brass window frames which were close enough in size and style, and I made window apertures in the model of the right size to fit these frames. For my first attempt, I had made an error in sizing the hut from the photos and created what would have been an enormous building. However, I was very pleased by the representation of the corrugated iron panels, so I had another go, and produced a much more modest sized building. Here it is painted up and just sitting on my test diorama.

Whilst waiting for Shapeways to print my model, I stumbled across a model uploded by someone else, presumeably a wargamer, of a wartime pillbox. Now, there was a pillbox in the goods yard of Freshwater, and, in fact, it is the only railway building still standing in its original position, albeit now in the middle of a garden centre carpark. Strictly speaking, the pillbox should be located just off the front of the layout, but I thought I would buy a reprint of the model anyway. It turned out to be a really nice looking model, and painted up, the brickwork looks really good. This gives me confidence to press on with the station building.

Monday 10 March 2014

Freshwater at the Basingstoke Show 2014

I love the sound of deadlines flying by. Having a deadline certainly provides a bit of impetus to get things done, even if not enough things actually get done in time.

When I accepted the invitation before Christmas, I had just about got all the electrical and mechanical gubbins beneath the layout working as required (see umpteen previous posts) and so, 4 years after the initial deadline for the 2mm Scale Association Golden Jubilee Expo in Oxford, I thought the time was right to start some scenic work. After all, with just one baseboard to cover, and four buildings to make, there was plenty of time. Then I started to make the starter signal. After a promising start, weeks turned to months, and with the above ground parts completed and working, I had to put it aside and start on the terraforming instead of trying to connect up a minute linear servo underneath.

So, after carving the layers of foamboard using a ceramic kitchen knife to produce a smooth land surface, and then covering with simple paper maché sprayed with brown and grey aerosol paints, I started laying the reed beds alongside the river, and along the tributary. This was plumbers hemp planted in glue and later trimmed with scissors and brushed roughly with green paint. The river water was Deluxe Solid Water resin which has produced the desired effect.

The rough ground cover was formed using a new product, which is basically a cooker hood filter that has been spray painted. I think it is quite effective as an initial layer. Shorter grass was static fibres, but the application was not as successful as on my test piece, with very little of it standing up properly.

Lots of fencing was added, mostly etched nickel-silver, but with plastic strip added to the uprights to give them more body. Lots more needs to be added, but I think I wiped out the stocks of County Rolling Stock's N'Tastic online shop.

Roads and platform surfaces are fine wet-and-dry emery paper, and the 3D printed trestle platform (see earlier blog) completes the platform. Various scatter materials, and a little plaster, completed the ground cover. Again, this is just the initial layer which will be toned down and added to later.

So that is how far it progressed before the exhibition. The layout behaved itself admirably over the two days, the main problems being with the DG couplings on some of the wagons which will have to be worked on before the next outing. Apart from that, it was a pleasure to shunt for an hour or two at a time. The 'to do' list now reads: Buildings, Trees, Signals, more fences, appropriate rolling stock.

Spectators. So it did have some interest from the visitors.

Some inappropriate rolling stock (except for the road van)

Station building is missing (amongst other things)

River Yar

The complete exhibit, with cantilevered fiddle yard floating to the right.