I promised more details on how the buildings have been illuminated. I have used LED strip light from Amazon; this particular set comes with a transformer plug to convert to 12v DC, with an in-line on/off dimmer switch.https://www.amazon.co.uk/gp/product/B07 ... UTF8&psc=1
The building I’m going to light next is the Maintenance Shed - without ducks, redheads or any other excitement except a steam engine!
The light strip can be cut in multiples of 5cm (2”).
The strip must be cut in the places marked with a scissor symbol, ie across the copper contacts.
All the components are sequentially numbered along the strip. R for resistor, D for (light-emitting) diode. Note that the copper terminals are marked +12v and -. From my secondary school physics, which was a long time ago, a diode allows current to pass in one direction, but not the other. A light-emitting diode emits light when the current is passing through; I’m not sure how, but probably by magic. The relevance of this is that the correct polarity must be maintained throught the entire lighting system, from the initial dimmer and through each building being lit. By this, I mean that positive (+) must be joined to positive, and negative (-) must be joined to negative.
Here we see that two lengths of light strip have been cut and stuck to the inside of the roof. There is a peel-off tape on the back of the strip to allow the lights to be fixed to a smooth, clean surface. Note the way the strips have been laid, so that D15 on one strip and D16 on the other strip are at the same end of the roof.
The copper terminals at each end of both strips are tinned with solder. I applied a small smear of flux to the copper terminal and then added a small blob of solder with a hot iron. Make sure the solder does not form a bridge between the two copper terminals; both must be kept electrically isolated.
Next I cut two wires to link the strips between D15 and D16. The short, bare ends of the wires were tinned with flux and a small blob of solder.
The tinned end of the wire is held against the tinned copper strip and the briefest touch with the soldering iron will melt the solder and join the two. Note that I an using the standard convention of red wire for positive and black wire for negative. This is not essential, but using two colours consistently throughout should avoid problems of mixing the polarity.
I’m using plugs and sockets to link the system together. The wire from the dimmer ends in a socket. The wiring to the packing shed has a plug on the input side and a socket on the output side and the garage has a similar plug on input and socket on output. The maintenace shed will need a plug on input, so it can attach to the output from the garage. It will have a socket on output which the next building in the chain can plug into. The wires from the lighing strips run down the walls of the buildings and through a hole in the building floor and then directly through a hole in the baseboard. The plugs and sockets join up under the baseboard. Using this method, the buildings can be removed from the baseboard when required.
I’m using stereo plugs and sockets, which mean there are three terminals in each plug and socket. I only need two of the three. Again, it is vital that polarity is maintained across the plug and socket pair. Further, I would definitely recommend wiring each plug and each socket in an identical way, so that the order of connection between buildings can be changed without messing up the polarity.
Here the black and red wires have been attached to the plug and the socket which have been pushed together. The clamping tags have been squeezed round the wires to hold them firmly in place. A word of warning here - make sure the leads are long enough to join the buildings under the baseboard. (Guess why I’m stressing this point!). Before continuing to the next step, screw the covers back on the plug and socket.
Tin the ends of the input lead (the one with the plug), as before, and attach the positive and negative wires to the LED strip at the end with the lowest numbered LED - D7 in this case. You did screw the cover on the plug before this, didn’t you? The wires are held in place using a hot glue gun. CAUTION - hot glue guns can burn worse than soldering irons!
Tin the ends of the output lead and attach to the other end of the strip chain (D24 in this case). Use hot glue to hold the wires and direct them to the point in the roof above the intended hole in the baseboard. Remember that the roof is probably upside down at the moment, so double check (and mark the roof) to make sure you are fixing wires in the right place. (Guess how I know this, too!)
At this point, the system should be tested to check all is well. Ideally, test this new build in isolation before adding it into a chain with other buildings. CAUTION - as plugs get pushed into, or removed from sockets, the polarity can get briefly crossed. Only make and break connections with the power off.
Return the building to the layout, thread the plug and socket through the holes and connect up. Switch on and admire!