Warning lights is
something very common in light (no pun intended) vehicles, trailers and
accessories. Sometimes they don't even have a bulb, just reflect light
from other sources. Unfortunately, most clear parts for this sort of
thing are devoid of any detail in plastic kits, while other times they
are simply absent. I'll show briefely here how I do warning lights. No
big secret, but I bet it will add a lot to your model.
The first step in producing a convincing light is to simulate the
relief pattern found on most lenses. Their purpose is merely to
increase the light reflexivity in other directions. Generally, they are
parallel lines grided either on the outer or on the inner surface of
the lens. I reproduce this by scoring parallel lines on a piece of
clear plastic using a hobby knife. Try to keep the lines as parallel as
possible, and check your references to know the number of lines in each
direction. Discs are then punched out to produce the lenses. During the
punching procedure, try to keep the line pattern reasonably centered.
Next, the reflexive layer is simulated by painting the backside of each
lens with silver color. Let it dry, flip the lens over and paint the
front side with the suitable transparent color. I used a mix of Tamiya
Clear Red (X-27) and Smoke (X-19) in this example. If necessary, add a
Wait the clear coat to dry throughly and apply it to your model. I like
to fix them using Microscale Metal Foil Adhesive, since that makes my
lenses self-adhesive, reducing the risk of marring the model with glue.
This method is particularly effective for small lights, and can be
adapted to your needs. In retrospect, I would suggest to apply a coat
of smoke or glase clear coat before the red/orange. That will work as a
wash, increasing the contrast of the relief lines.
I hope you find this tip useful.