If there's one inescapable fact about T Gauge, it's that everything is small. A recent discussion at Talking T Gauge shifted from a new member introduction to a brainstorming session on lighting—in particular, streetlights. Since I need some for my layout, I thought it would be the perfect opportunity to have a crack at making a functional one at 1:450.
Lately I've been busily creating a number of lighted effects in Z scale, including a crossing flasher, a signal, and a light over a door. These have served as very useful exercises in working with the smallest of the small: 0402 SMD LEDs, which measure a mere .040 x .020 inches (1 x 0.5 mm). The smallest commercially available LEDs, they're well and truly for use only by modeling masochists with extraordinary eye-hand coordination and plentiful patience.
After assuring Talking T Gauge members that it was feasible, I decided it was time to put my money where my mouth was, and actually build one. My thought was to allow the LED itself serve as the light head, with nothing else added in the way of a housing. In T, the LED would measure about 9 by 18 scale inches, a believable size for a streetlight head. The wires powering it would form the arm and brace parts.
I started by soldering a length of .008-in. brass wire to one of the LED terminals. After cutting the wire to length and bending it to shape, I soldered the other end to a length of .018-inch brass wire. Then I fabricated a base by drilling endwise into a piece of .040-inch square styrene strip stock; I sliced it to length and bonded it in place (about 20 scale feet from the top) on the brass pole with CA.
Next, I soldered a piece of #43 solenoid wire (only slightly thicker than human hair) to the other LED terminal, and secured the free end to the top of the light pole with CA. Then I positioned the solenoid wire against the back of the pole and bonded it in place. The wire is so small that it only shows up in macro-photos.
After a quick test to be sure the LED worked—and it sure did, with far too much brilliance to be realistic—I sprayed it with two light coats of pale grey primer, LED and all. The grey primer turned out to be about the right color, and the LED is so brilliant that I didn't even bother to scrape away any paint; indeed, the brightness is now toned down to an acceptable level.
Although 1:1 streetlights come in a dizzying array of shapes, styles, heights and configurations (not to mention that many new LED-based lights are popping up now), I wanted the model to be as generic as possible. This, I believe, helps to make it more realistic. I also deliberately used a plain white LED, as opposed to a "warm" white, because I think the pale blue tint nicely captures the look of a mercury vapor lamp.
The project took about an hour and a half, but I think I can bring it down to around 20 minutes, now that I know what to do. My next illumination project will be a working crossing flasher. Having just made one in Z, I'm ready for this challenge in a major way.