Friday, 17 February 2017

Trains move on Camford Junction

A major milestone has been achieved , with trains running on part of the layout for the first time. I have been putting together a collection of cheap, ready made electronic modules with an Arduino to produce a quintuple analogue DC controller that is operated via commands sent through the Merg CBus. It can be operated using Merg hand-held controllers (CANCABs), or via a PC running JMRI and smart phone throttles. It is still a bit experimental at the moment, but is developing into a usable system.



The one baseboard of Camford Junction is fully wired up for the 4 main lines, and this was used for tonight's test. Unfortunately, only N gauge locomotives were available, and their wheels and flanges do not pass through the finescale pointwork, limiting how far two of the tracks could be tested. I also only have two CANCABs and did not have time to set up the PC and WiFi network, so we could only run two trains at a time. However, the test was reasonably successful, as can be seen in the video:

Video on Flickr

So, now I need to get on with the wiring of the second baseboard, while the others lay some track for the TMD on the first board, in an effort to have trains running to and fro in time for a display at the Basingstoke model railway exhibition in March.

Thursday, 2 February 2017

"You're just wasting your time"

Obvious quote from "Oh, Mr Porter" describes this morning's activity. Using some plastic card and some printouts from Scalescenes, I started on the interior of the Station Master's house:


And what can you see once it is in place?

Tuesday, 31 January 2017

A Little Destruction

With only two weeks until the Newbury exhibition, taking a chisel to the layout might seem a bit foolhardy. However, I had a few jobs I wanted to complete before showing the layout again, so I have booked a few days holiday to get them done.

The first job is to extend the station concourse. Having acquired more photos and information, it was apparent that I had underestimated its size, as the W.H.Smiths bookshop and newsagents was sited between the station building and the signal box. I have moved the buffer stops almost two inches closer to Newport. I positioned some plastic card and foamboard as foundations for the buildings and concourse surface. The headshunt is still long enough for a Class 33 to run round. The prototype was only just long enough for an O2 to run round, but that would be a bit restrictive for my layout. The ground surface can now be remade.

A little more destruction along the rear of the platform was caused by the removal of the over-height etched fencing which will be replaced by 3D printed Southern Railway cast concrete palings that I have created.

Wednesday, 18 January 2017

Some more buildings for Freshwater

Not much has been happening on Freshwater for a few months as all my modelling time seems to have been spent making up Merg electronic modules for other peoples' layouts. But this is about to change as I have an invite to the exhibition in Newbury on February 11th. I had set myself a deadline to get the station building and surrounding area sorted, and some more trees planted before this. So, over the Christmas period, I spent some time on the laptop fiddling with Blender to get the signal box and W. H. Smiths bookshop ready for 3D printing. I had also received an old photo showing the side view of the corrugated iron goods shed. My previous 3D printed model of this had been made using just a distant, end view, and I had imagined double doors would have been fitted on the sides. This new photo showed just a single door, and a brick built plinth. I therefore editted my Blender file, and got a new 3D print. The images below show the 3D prints, as received from Shapeways, having just cleaned them with acetone-free nail polish remover, and given them a light spray with Tamiya fine grey primer. I hope my painting skills will be up to the task of finishing these off. I have to find some suitable window frame etches to modify to fit, as nothing off-the-shelf was appropriate.

Corrugated Iron Shed, version 2.0
 and the newly acquired photo of the original
 W. H. Smiths
 and the original
 Signal Box (kit of parts)
 and the real thing (also showing W. H. Smiths bookstall and station building beyond)


The station concourse is larger than I imagines, so I will have to move the buffer stops and rebuild the concourse/platform a little to fit the bookstall where it belongs. I have also 3D printed some SR standard concrete paling fencing to finish off this area, as the etched brass fencing I fitted originally is much too tall.

My first attempt at the iron shed included the pointy finials, similar to those on the signal box, but they broke off in transit. I, therefore, re-created them as a separate set of 6 (with a sprue) printed in FXD which will be added to the shed and signal box later.

Tuesday, 30 August 2016

A busy evening with Camford Junction

A busy club evening, with Robin building more points for the TMD area, Graeme fitting point servos on the second board, and Pete and I painting track on the first board in preparation for ballasting.

So, for a change, some views of the tops of the baseboards.

The two scenic boards:



The first two crossovers:
and some of Pete's stock that will be running on the layout, one day:


Wednesday, 24 August 2016

More wiring on Camford Junction

After a few club-nights the main line wiring on one board is finally complete. The amount of wiring would have been a lot less if we had gone for DCC, but I am the only member of the group with DCC fitted stock, and it is not of the right era for the layout, so I lost that battle.

The relays, controlled by Merg CBus modules, switch the various track sections between the 4 main line controllers. There are only 3 points on the main line on this board, controlled by the black Merg CBus CANSERVO8 module.

The wiring along the edge of the layout consists the 4 controller feeds, 12V and 5V power supplies and the CBus pair. The wiring down the other side of the raised section is the feed from the relays to the track sections. The expanse of virgin white board, where the documentation is laying, will be home to the MPD, and will be covered with servos and more Merg CBus modules eventually.

 Meanwhile, the second board has had most of its hardware fitted and will be ready for wiring up to commence while track laying for the MPD area can start on the first board. This board also has just 3 points on the main lines. The tie-bars have been fitted and the servos will be fitted next week, hopefully. Note, the elevated secondary main line diverges from the main, main line on this board, running along what will be filled, brick arches.

Wednesday, 25 May 2016

What goes on below Camford Junction

Now that the elevated main line tracks have been laid, I wanted to make a start with the hardware and wiring below the baseboards before track laying in the lower  depot area started. Firstly, individual dropper wires were soldered to each separate length of rail, and pushed down through holes drilled in the baseboard. The dropper wires are single strands from a multi-strand cable. Each one is like a piece of fuse wire, but being just a couple of inches long has been found completely reliable on a number of 2mm scale layouts we have built.

Below the baseboards, the dropper wires are joined to solder tags screwed to the woodwork. These will later be linked by proper, multi-strand hookup wire.


The photo also shows a cheap relay module found on eBay. These relays will be used to connect the four analogue controllers to the various track sections, dependent on the selected routes.

The points will be operated by cheap RC servos. These are mounted in aluminium 'Dingo' servo mounts, which allow the servo to travel fully while only moving the actuating wire a few millimeters. This is important for slow and quietly smooth movement of the point blades. The mounts also include micro-switches that can be used to switch the frog polarity and give position feedback to a control panel.

The under baseboard tie-bars I designed for this layout are 3D printed, and are now available from the 2mm Scale Association shop.


The layout will use the Merg CBus layout control bus (LCB) which is designed to reduce the amount of long runs of multiple wires, requiring only 4 wires between a control panel and the layout. Various actions, such as pressing a button, or a train being detected in a section, will cause numbered 'event' messages to be broadcast across the bus. Other modules will be taught to act on specific events, switching relays, moving servos, lighting LEDs, or whatever. There will still be a lot of wiring, but most will be short runs, contained within a single baseboard. The bus concept is also more flexible than conventional wiring, as modules can be taught to act on new events, or perform different actions for existing events, as the layout evolves. This photo shows a CANACC8 module (which produces 8 steady-state outputs) that will control the two relay modules. I still have to attach a CANSERVO8 module, that can operate up to 8 servos, but this will also operate some of the depot points, so I need to determine the best location for it to minimise the wire lengths required to the servos. Servos can jitter if they pick up electrical noise in their wires, especially with analogue locomotive control. Surprisingly, DCC locomotive control is not such a problem.


To assist with setting up and positioning the point tie-bars and servo mounts, this little servo tester I found on eBay has proved very useful. It can move the servo to its centre position at the push of a button, or you can use the knob to manually move the servo, or it can work automatically in 'windscreen wiper' mode.

So, next week, I can start adding some wires.