Sunday, October 21, 2012

Vickers Wellington MK XIV

Another plastic kit finished, airplane Vickers Wellington MK XIV, 1:72 scale model from Trumpeter.

 That was one of the most important bombers and produced for the entire duration of the Second World War. It participated in the first night raid on Berlin on 25 August 1940. In the first 1,000-aircraft raid on Cologne, on 30 May 1942, 599 out of 1,046 aircraft were Wellingtons. With Bomber Command, Wellingtons flew 47,409 operations, dropped 41,823 tons (37,941 tonnes) of bombs and lost 1,332 aircraft in action.

It's been a nice practice of painting techniques that I plan to use with my recently acquired Star Wars models. But it's a pity most of the hard work will never be seen, because it's in the interior of the plane. I painted radio room, controls, wood panels, dry brushed metallic parts, applied pigments to the floor, .... even the chemical toilet was documented and painted in the right color!!! I found few original photos in internet and a 4+ publication called "Vickers-Amstrongs Wellington Medium Bomber variants" with a lot of information and photos:

I used black Citadel primmer for the interiors and white Tamiya primmer for the external parts. White Insignia was Tamiya Bright White, and camo from Vallejo Model Air colors, all airbrushed. The only difficult part on this is the correct masking of windows. Tamiya tape works perfect, but I did some mistakes because I didn't stick firmly all the edges of the tape and paint sliced a bit under some parts of it.

After the basic color painting, gloss varnish was applied to have a "restore point" if something goes wrong with the weathering. Than weathering consisted in the appliance of washes to accent the panel lines and details. First in black for colored parts and blue-gray for white parts, and some brown general wash to give a dirty look to the wings. I hadn't oil colors for washes and tried water oils (Van Gogh water colors . It's and acrylic paint, in oil form, but water soluble. It gives the benefits of acrylic paint (toxicity, smell, easy to clean, ...) and the benefits of oils (long time to dry, allows to work with effects, correct, diffuse and shade off, ..), but with a surprising effect I will use for many other plastic kits for sure: It's very transparent when diluted just in water. It's easy to use it for filters and control the grade of transparency. If it is already applied, doesn't matter if it is dry, you can thinner it just adding water with a brush and get very good effects.

Around the engine and exhausts I applied black pigments, and light gray pigments to the wheels. Finally the chipping, mat varnish applied with airbrush, and gloss varnish to the windows and chippings with brush.

This model is 1:72 scale, so it's too small for realistic effects, and usually nobody puts the radio cable because there's nothing to use thin enough. But I found the right thing to use as the radio cable (you can see it in the photo above going from the rear vertical stabilizer wing to the front): a hair of my girlfriend!!!!! Thanks she didn't cut it short!!!! xDDD

Wednesday, October 17, 2012

GCA50 Loconet Interface

After some general schematic posts about Loconet and Giling modules and interface, I'll continue with the main Loconet interface: GCA50

Before entering in details, some terminology clarification: Giling page uses the word "interface" referring to both Loconet connection board and I/O boards (those connecting servos, turnouts, current detectors, wheel counters, ....). Sorry Peter, but I find this a bit confusing. I will refer first ones also as Interfaces, but I will call Drivers to the others to avoid confusions. Interface boards connect any kind of Driver board to the communication bus. It can be Loconet (GCA50), or CBus/CAN (CAN-GCA series boards). And Driver boards "drive" servos, turnouts, detectors, lights,....

As my installation began with an Intellibox Basic and Loconet bus, my main board is GCA50. I can insert as many GCA50 boards as I need in Loconet bus. They are fully compatible with any other Loconet modules (now a days I have a mix with Giling and Uhlenbrock modules).

There is just one difference with standard Loconet modules, the connector. Standar loconet uses RJ12, but Giling modules use DB9 connectors (those 9 pins connectors used mainly in RS232 devices).

Quoting Giling words, and I agree with them, the reasons for that are:

1) Units have to be connected / disconnected many times, which is not suitable for RJ12 connectors.
2) GCA would like to have suitable power over the cable, which Railsync is not able to provide.
3) The LocoNet railsync should remain be available.

And I add they are easy to connect as you don't need special grimping tool. Point 2 also helps a lot in wiring because there's no need of more power wires to the modules, everything is embedded in this connector (Loconet signal and power).

Giving a summary: GCA50 is the board connected to your Loconet bus, and you can connect up to 2 driver boards to it for current detectors, switch control, lighting, wheel counter, servo controlling.... And it's also possible not to connect driver boards and use the input/outputs to connect directly switches and leds (to make a control panel). More information on connecting leds here:

But let's see how it looks like (processor is missing):

On the top there are Loconet DB9 connectors, male and female. You connect loconet bus in one of them, and extend to the next GCA50 through the second one.

In the lower part there are two 10 pin header connectors (white). That's the connection to Driver boards, so you can connect two driver boards per GCA50. Each connector delivers 8 Inpout/Outpus (it's configurable).

The smaller header connector in the center is used to direct programming of the microprocessor.

And in the lowest part there is a screw terminal. This contains exactly the same signals corresponding to Driver connectors, but in screw terminal form. Here you can connect directly devices (leds, reed, ...) but taking into account it's low power. Normally a Driver board is used because it hasn't enough power to drive any kind of switch, servo or whatever. I don't solder this connector because I never use it and it's one of the most "expensive" components. Anyway, NEVER solder directly here, and get used to connectors, they can save your life....

That's a GCA50 connected to a servo driver board:

Now, in which ways can you buy this board??

1) I don't have money or I'm really skillful and I like electronics problems: Just download "pcboard and parts position" PDF file from Giling page, isolate your board and assembly. Download also HEX pic file and you are ready to go.
2) I'm not so skillful or I don't have a lot of money: you can buy only board, or board plus preprogrammed pic. But in my experience you will not get a cheaper bill than buying the complete kit
3) I know soldering, I like to build my devices but I don't want much problems: buy the complete kit (board, components and pic).

For more information, go to this Giling page: or surf his web site.

I finish just adding that programming is really easy (from Rocrail) and I had 0 problems in my five operative GCA50.


Friday, October 5, 2012

Connection Bus

For those having Intellibox as the heart of the installation, I'll show you how to adapt Giling modules to your Loconet BUS. I started using Uhlenbrock modules, but due to its price and lack of functionality (mostly in servo modules), I decided to change to Giling Loconet modules.

If you already have Uhlenbrock modules (or other Loconet modules), is possible to add GCA50 as any other loconet compatible module. That's how I started:

You can see GCA50 is just "half" loconet module. It's an interface between Loconet BUS and any other interface module. Instead of investing in electronics in each module giving them a Loconet connection, you plug a GCA50 and combine 2 interface modules as you need: reversing loop module, switches or lighting module, servo management, weel counting....

And the final schema I'll have in my installation is the following:

Intellibox has not enough power to drive more than 5 GCA50 (in my experience), and the solution is to add a GCA101 Ethernet interface + 3Amp power source. And your layout will be connected to the net and you'll be able to drive it from any device connected to it.

Short post, but self explaining hopefully!!! Cheers,