Alien Projector By Brian McNamara
Shine an alien, large or small, on any wall.
This simple projector shines an image of an alien
on the wall. It uses an LED as the light source and
projects an image varying in size from a few inches
to several feet. The simple circuit consists of only a
battery, resistor, switch, and LED.
YOU WILL NEED
1. Build the basic circuit.
Trim the resistor and LED leads to ¼" long, and
solder 1 end of the resistor onto the negative lead
of the LED. Cut about 6" of wire, and solder it to
the positive lead of the LED.
Put a piece of heat-shrink tubing over the black
(negative) wire of the 9V battery clip, then solder
the wire to the other leg of the resistor. Solder
the red (positive) wire from the battery clip to the
middle terminal of the switch. Place heat-shrink
tubing over this wire if you wish.
Solder the positive LED wire to one of the outside
pins of the switch.
Switch SPST panel
6" of wire
9V battery and battery
1¾" PVC pipe, 6½" long
6" balsa wood sheet,
2"×½" balsa wood
stick, 4" long
Hot glue gun
2. Build the case parts.
Print the templates of the front and back plates, cut
them out, and tape them to the balsa wood sheet.
With a sharp knife, cut out the inside of the template
first, then the outside. Use the cross on the back
template to mark the hole for the switch.
Cut two 1¾" lengths of balsa wood stick. With
the knife, drill a
6" hole in the middle of one, and
a ¼" hole in the middle of the other.
Drill a ¼" hole in the middle of the balsa back
plate where it’s marked, then glue the stick with the
¼" hole to the back plate.
3. Put it all together.
Glue the LED into the stick with the
6" hole. Fit the
switch to the back plate. Fit the LED stick into the
middle of the PVC pipe, then glue the front plate
onto the pipe. Snap the battery into the battery clip,
then fit the back plate into place.
To set up the projector, place it in a dark room 1'– 4'
from the wall. Move it closer to the wall for a smaller
image, and farther away for a bigger image. The best
thing about this project is that you can cut out any
simple image and project it onto the wall, perhaps
pumpkins for Halloween and a tree for Christmas.
Brian McNamara lives near Canberra, Australia. By day he works in a university workshop designing and repairing
equipment for a biological research facility; by night he designs, hacks, and bends kids’ toys and musical instruments.
Photography by Brian McNamara
104 Make: Volume