Wednesday, 21 February 2018

More Progress on Camford Junction

Following a short tuition session last week, the guys are now in full swing creating 500mm lengths of plain soldered track for the fiddle yards. Soldered track is more robust, and much cheaper, than EasiTrak although it does not look as good. It will be fine for the fiddle yard. The fiddle yard will gobble up over 70m of straight track, plus lots of curved track around the ends and 16 points. We may be some time.

Meanwhile, now the wiring on boards 1 and 2 is complete, I have powered them up and attached the laptop to the CBus with a plug-in CANUSB module. I used the Merg Flim Configuration Utility to update the firmware on all the CBus modules to the latest revision, and then started assigning separate event numbers for each point and each relay. Crossovers on the main line use a single event to operate both points. Main line track sections use pairs of the single pole relays to switch both rails between controllers, while the MPD area, which will only be associated with a single controller, uses a common return and just a single relay for each section. I documented the events, and the associated CBus module outputs in a spreadsheet as I progressed. Then I set up all the events in the turnout table in JMRI. Initially, JMRI only had two tables, 'Turnouts' for outputs and 'Sensors' for inputs. Over the years, extra tables have been added for 'Lights' and 'Signals', but there is not one for 'Relays' yet, so they will have to live in the 'Turnouts' table for now. Now I have all these captured in JMRI, I can proceed with setting up the layout schematic, with the turnouts, blocks and routes, and then work on route selection and setting the relays using 'buttons' on the layout screen.

Saturday, 17 February 2018

Stroudley LBSCR 4 wheeler carriages

OK, I know they did not survive into the 1950's but a 4 car set was used on the Freshwater line, so that is good enough for me. The brass etch for the bodies is available from Etched Pixels. They suggest putting them on chopped up peco wagon chassis, but I thought they would look nicer on etched chassis. The GWR 4 wheeler chassis from David Eveleigh is almost perfect for length. I could not figure out how to fit the footsteps provided, and the Stroudley set only had a single footstep, except below the guard's doors, so I have decided to try to etch some new solebars, with queen post and trussing and some bolt head details, and new footsteps with brackets to add on. I am also adding some buffer beams, although I might 3D print them complete with the short buffers needed. I was working on drawing a set of etched window frames for the signal box and magazine stand, and have only used a very small area of the smallest standard panel that can be etched. Progress on the etch drawing has been pretty slow as I try to learn how to do what I want in DraftSight.

Meanwhile, here is construction progress so far. The carriages were drilled for hand rails and door handles before folding up.

Sunday, 31 December 2017

Posing for the camera

At the Euskirchen exhibition, I asked Peter to use his camera to try to replicate some of the source photos I have of the real Freshwater. After some manipulation, here are the results:

It shows some irregularities, and focal length differences, but the main one is the position of the buffer stop in the horse box photo. It is positioned correctly according to the OS map, but does not match the photographic evidence.

Tuesday, 14 November 2017

Still working on Camford Junction

The Camford Junction group was hard at work on Camford Junction again last night. Progress is slow, but it is progress, nevertheless.

There was much discussion and head-scratching trying to work out the best shapes for baseboards for the curved ends of the fiddle yard that will allow for the 4 tracks, with a minimum radius of 36 inches, and with the tracks crossing baseboard joints as close to right angles as possible. We also want to provide a few inches of straight track at the joins to the straight baseboards at the front and rear of the layout, and increase the spacing of the tracks to allow for overhang of long coaches and wagons.

Meanwhile, droppers were being added, and connected together on baseboards 3 and 4:

And I pressed on with joining up droppers with relays and frog switches for the TMD area on baseboard 2:

Wednesday, 30 August 2017

What a load of old bull-rushes

With another deadline about to whoosh past (exhibiting at Andover this weekend) it is about time I added a bit more scenery to the layout. I picked up a couple of boxes of Noch laser etched bullrushes to add to the plumber's hemp rushes I had already planted along the river Yar and the brook that runs along the rear of the station. I found some more on eBay, and in the end, I have almost 150 bullrushes to plant. They do not go far, as you need to group them to look effective, and even then, they are hardly visible. This photo shows about a third of them.

Sunday, 14 May 2017

And then there were two - 2

Having had a successful weekend running 'Freshwater' on 'Freshwater' at Abingdon, I have now turned my attentions to a second Dapol A1X Terrier locomotive, carefully copying the process that worked with number 8 'Freshwater'.

The chassis is etched nickel-silver, available from the 2mm Scale Association along with suitable wheels and gears and 'muffs'. A Nigel Lawton motor provides the power, and a CT electronics DCC decoder fits in the cab. Some extra lead weighting has been added inside the tanks.

Having got the chassis working well enough on analogue DC, I fitted the DCC decoder, and now it runs very nicely on the rolling road. It is not so good picking up from the tracks yet, but I have still got to fit the rail-top pickup scrapers and the DCC stayalive capacitors that Freshwater has.

This locomotive will become number 13 Carisbrooke, and will be lines southern olive green with BRITISH RAILWAYS in sunshine lettering, if I can find a supplier for the lettering and nameplates.

And then there were two - 1

For exhibiting 'Camford Junction' at our show in Basingstoke back in March, I had cobbled together various modules purchased on eBay, controlled by an Arduino, all screwed to a piece of wood and joined up with a bird's nest of wires. This provided the five analogue DC controllers to drive the trains on the layout. By pretending to be a Merg DCC Control Station (CANCMD) it allowed Merg hand-held throttles (CANCAB) to be used to control the trains. It also meant that JMRI, running on a laptop, could also provide on-screen throttles, and by hooking up a WiFi access point, Android and iPhone throttle apps could also be used to drive the analogue DC trains.

Having performed faultlessly all weekend, I had to tidy it all up, and put it into a proper case for protection. This has taken longer than the original build.

I have also been thinking about the problem of failures and rectification of faults during an exhibition. With a club layout, there will always be some concerns amongst the membership about the reliability of new technology. For Camford Junction, I have tried to make fault rectification as simple as possible, by standardising and separating things. The layout is powered by several identical laptop-style 12VDC power adapters. We will have a spare one that can be used to replace any one of these in the event of a failure. So far, I have used only two types of Merg CBus modules, the CANSERVO8 module to control up to 8 point servos, and the CANACC8 module (modified for 12V DC power) to operate a standard 8-relay module widely available from eBay, to switch track sections between controllers. We will carry a spare for each module, which can be quickly swapped if required. It will be necessary to plug in the laptop to load the configuration data into the new module for its new location.

The new control box is a different matter. If one of the other layout modules fails, it will disable a few points or a few track sections, but if the control box fails, the whole layout will grind to a halt. Repairs under exhibition conditions would also take some time. The simple answer was to build an identical spare. Fortunately, the total cost of all the modules in the case is reasonably low, but it did require a lot of drilling holes, crimping, and soldering. The end result, twins:

The next step will be to add a Raspberry Pi (a very small Linux computer) into the control box that will run JMRI and provide WiFi access, instead of having to plug in a laptop.