I wanted to add working tail lights to the last car on my Amtrak California Zephyr train like the ones in this prototype photo.
So I decided to make my own working tail lights on one of my Amtrak sleeper cars.
The stock lenses are solid red plastic so I replaced them with my own made from .040 fiber optic. I mushroomed one end by holding it close to my soldering iron. This helps the fiber optic capture more light. After cutting to the right length, the cut end was sanded smooth.
The openings left by removing the stock red plastic lenses needed to be slightly enlarged to fit the new fiber optic lenses. Then the fiber optic lenses were installed from the inside.
Using some small LED's from one of my boards, First I tried to paint them red but when gluing them in place the red paint dissolved so I made filters from disks punched from a sheet of .010 red translucent polystyrene sheet.
A simple circuit of bridge rectifier, 5 volt voltage regulator, and super capacitor are attached to the bottom of the upper deck with E6000 adhesive.
Some of the interior walls had to be notched or removed from the floor section for the circuit to fit.
So that the circuit components would not show through the lower windows, those windows were painted a gunmetal color from the inside giving them the look of being darkly tinted.
Once the windows and upper deck were re-installed the circuit was tested for a couple hours to make sure the components would get hot. They don't even get warm because the current used is very small.
And this is the result was looking for.
Because DCC power is always on the track, the LED are always lighted. And with the super capacitor in the circuit acting like a "keep alive" circuit they don't flicker with interruptions of contact and will even stay on for several seconds when the car is removed from the track.