Model Railroader – September 2019

44 http://www.ModelRailroader.com

Fortunately, small backlights are inexpensive, costing less

than $3. The backlights shown in ❶ are about^1 ⁄ 8 " thick. I pur-

chased mine from Adafruit (www.adafruit.com).

Installing the backlights

The building I illuminated is a four-story warehouse. After

installing the clear window glazing, I cemented^1 ⁄ 8 " square sty-

rene strip along the inside of the windows ❷.

I covered the windows that wouldn’t be illuminated with

gray construction paper. I then installed the backlights and

bent the leads up at a right angle ❸.

Next, I cut a piece of^3 ⁄ 16 "-thick ABS plastic so it friction-fit

between the walls (don’t glue the plastic in case the backlights

need to be repaired or replaced). After drilling holes for the

LED leads, I set the plastic into place ❹.

Running the wires

I next soldered 2-foot lengths of stranded wire to the LEDs,

using red for the positive (longer) leads and black for the nega-

tive leads. Note that I tied the negative leads together so I’d

have one fewer wire to route ❺, opposite. I kept the positive

leads separate so I could control the upper and lower modules

independently. I covered the connections with heat-shrink tub-

ing. Then I taped the wires to the ABS to hold them in place.

Before putting the low-relief building back on the layout,

I drilled a^1 ⁄ 4 " hole through the backdrop ❻. I threaded the

1" x 3" backlight 2" x 3^1 ⁄ 2 " backlight

Leads

(^1) ⁄ 8 " square styrene strip
Gray construction paper
LED backlights
Bend leads at right angle^3 ⁄ 16 "-thick ABS plastic
Holes for
LED leads
❶ Backlight examples. These two backlight modules are
sold by Adafruit (www.adafruit.com). The devices capture
light from a white light-emitting diode and uniformly spread
it throughout the thin acrylic sheet.
❷ Styrene strip. With the window glazing in place,
Mike added pieces of^1 ⁄ 8 " square styrene strip. The styrene
strips serve as a frame, holding the LED backlights in
place horizontally.
❸ Installation. Mike covered the unlit windows with gray
construction paper. He then set the backlights in the structure
and bent the LED leads at a right angle.
❹ Holding the backlights. Friction holds a^3 ⁄ 16 "-thick piece of
ABS plastic between the walls. The LED leads pass through
small holes Mike drilled in the plastic.