The instructions on the Signals Branch blog for my 3D printed signals discuss using 0.8mm SMD LEDs to light the signal aspects so here are a few photos showing how I did a bracket signal.
Firstly it is best to buy the SMD LEDs pre-wired, they can be bought without wires but they are so small that soldering very fine wire is difficult.
The lamps on the signals have a slot in front and back. The rear slot is to allow the wires to come out and the front is a slot as the minimum wall thicknesses make it difficult to have a lens or hole.
The 0.8mm SMD LED will be a slight push fit into the hole in the top of the lamp and the square LED sticking out of the front of the tiny circuit board will fit into the front slot.
The 0.8mm SMD LEDs are to be gently pushed vertically into the body of the lamp. I found that I had to use my finger nail to push it in but a toothpick would also work. Don't use a metal object to push the LED home as damage may be done to the fine wire on the top end. The other wire is at the bottom of the LED. Ensure that the wires align with the slot at the rear of the signal as it is pushed into place.
The wires from the small outrigger dolly post of the bracket signal were threaded under the landing and then through the angled bracket supports under the rear of the landing and then down the main post.
The wires from the lamp on the main post were run down the back of the post around the end of the landing and then down the back of the post.
Glue the wires to the signal with Super Glue progressively stopping at each change of direction.
A small circuit board can be made from a printed circuit board (PCB) sleeper or with a piece of PCB cut to size (4mm x 15mm). The copper on the PCB is cut down the middle of its length with a fine stone in a hand motor tool (Dremel, etc.) and then one side of the copper is cut at the half way point. A 1K Ohm resistor is soldered across the half way gap, this is the +ve side of the circuit. The other copper strip is the -ve side of the circuit.
A small 2 pin plug and socket is made by cutting up an integrated circuit socket. solder the long pins of one half to each side of the circuit board as shown on the diagram and photo below. Solder the wire from the LED to the two connections at the other end of the circuit board. The longer wire of the LED goes to the +ve terminal and the shorter wire of course goes to the -ve terminal. I have used a 1K Ohm 1/2 Watt resistor so that the light shows through the spectacle plate of the arm during daylight but any value from 1K Ohm to 10K Ohms could be used, your choice. 10K Ohm will probably not show during 'daylight' (room lights on).
Glue the circuit board to the signal where shown in the photo below and tuck the excess wires of the LEDs out of the way up in between the two halves of the mechanism.
The wires on the male plug are soldered across the two holes rather than into the holes, this is needed from clearance from the main operating crank of the signal (see photo).
|Signal Circuit Board Diagram|
|Signal showing small homemade circuit board|
|Lit LEDs during 'daylight'|
|LEDs lit during 'night' - No signal arms.|
|Glowing bracket posts|
|Lit signal arms during 'night'|
I found that the LED was not yellow enough to give a green glow through the Tamiya X23 Clear Blue so I give the blue lens a coat of Tamiya X25 Clear Green.
Now it looks like I will have to light the Brakes Landmark, what have I started....
Installing lights though is a long term project for Bylong as I would like to operate eventually at 'night'.