The finish could have been even better, but this by far supersedes what I could have made myself.
The showcase is in birch plywood. 155 mm in top and bottom and 12 mm for the shelves. The back is masonite, with white paint on the visible side.
But there is no light in the showcase. And there should be lights so that I can enjouy my rolling stock.
I have bought two roles of 5 m long LED strip in Jem&Fix. It is about 140 kroner per roll. And the 10 meters leaves quite a bit for lights in the shadow yards.
An experiment shows that if the LED strips are to shine their light on the trains, they need to be placed at the edge of the shelf above and in an angle of 30 or 45 degrees.
The LED strip is 8 mm wide. Where does one find a triangular wood strip in that dimension? Not in Bauhaus or Silvan.
Modelskibet.dk has en plastic profile in the right dimensions. But I don’t want plastic in my showcase. It needs to be wood. And it is quite pricey too – about 30-35 kroner per meter.
Instead I have found balsa strips here: http://www.iccom.dk/shop/product_info.php?cPath=372_377&products_id=12740&osCsid=s16ms3g65d6unq50cct3rosff1
I bought 7 strips, 1 meter each. The showcase is 120 cm, i.e. 117 cm inside. And the LED strips can be cut for each 10 cm.
I could therefor use 1 strip per shelf and thereby 1 meter of LED strip. Or I could fill the entire shelf with balsa and use 110 cm LED strip. Experiments show that the 1 m LED strip leaves the ends of the shelves in darkness. So the solution is 110 cm.
I have not been using screws. Everything is glued together.The picture is taken from above with the showcase standing upside down on the floor with the LED strips loose on the underside of the shelves. However, I have turned the picture upside down too, so now it looks as if the picture is taken from below:Looking closely at the picture, one can see two different kinds of LED strips. The one below is from a package I bought a year or two ago. It is stiff and har to work with. The one above is a new kind that I just bought. The new one is with a layer of some soft plastic-like stuff, which makes it softer to bend. I think I will be using the new kind all over, so I will have to buy another packet.
And then the problem with wiring: I need something thicker than a single lacquered copper wire. But how do I avoid making the wiring very visible?
I am going to drill a hole in the back of the showcase at one end underneath each shelf. And then I will solder all the wires together behind the showcase. But since the back is just a flat piece of Masonite that should be flat against the wall, there is no room for wiring. So I have bought some wood strips of 5 x 33 x 1200 mm, which I will be placing in a square around the edge on the backside, so that I will get an air gap of 5 mm to do the wiring in:Regarding power supply, there is a 12V / 1A power supply with each packet of 5 m LED strip. It also says 9W on the packet. I suppose that means that 5 M LED strip + the loss in the power supply adds up to 9W being pulled from the mains.
I would like to ensure that one power supply can manage the entire showcase. And since I am using 6,6 m LED strip corresponding to 1,32 packet. If there is no loss in the power supply, that would mean that 6,6 m would need 1,32 * 9 W = 11,88 W, which is very close to the 12 W the power supply is labelled with.
An other way to estimate the power consumption is this: For every 10 cm of LED strip, there are 3 warm-white LEDs in series and with one 310 ohm resistor. According to http://www.petervis.com/electronics/led/led-resistor-calculator.html the voltage drop across a warm-white LED is between3,2 and 3,8 V. Using worst case, it means that every 10 cm strip uses (12 – 3*3,1) V / 310 ohm = 7,74 mA. I.e. all 6,6 m LED strip uses 66 * 7,74 mA = 511 mA or about half of aht the power supply should be capable of.
All things considered, I will take the chance and use the one power supply.