LED Flat Flashlight


Materials:
  • 5 mm or 10 mm white diffused LED light (We got ours from Evil mad Scientist, which unfortunately they are no longer selling. Other suppliers All Electronics, Goldmine Electronics, or Amazon)
  • 3V lithium coin battery (we got ours from sciplus.com item # 40919)
  • copper tape (found in the gardening section of hardware stores as an anti snail/ slug product or alternatively in 1/4'' form on Amazon)
  • electrical vinyl tape
  • jumbo craft stick
Tools:
Scissors
Ruler (optional)



Cut copper tape long enough to go down the length of the craft stick and to wrap about 1/2'' to the other side.



Place your coin battery on to the short piece of copper tape you wrapped over the end of the stick with the positive side of the battery facing up, negative side down touching the copper tape.  Take a shorter piece of copper tape and fold each end over about .75'' each side, leaving the middle section with adhesive, and adhere it to the craft stick making sure one end of the tape is over the coin battery. The copper tape we used, glue is not conductive so you have to fold over tape to allow the electricity to flow.  In the image above, the right side of the top copper tape is the positive battery contact and the left side is the switch contact.


Be sure that the copper tape under the battery is not in contact with the top copper tape.  Add a final piece of copper tape from under the switch contact to the top of the popsicle stick. Secure the copper tape battery contact onto the battery with electrical tape.


Place LED light on the end of the craft stick, with the long positive lead of the LED on the switch side of the flashlight. Above image shows the flashlight with the switch open and the LED in place. Test the flashlight be pressing LED leads against copper tapes and complete the circuit by connecting copper tape switch onto copper tape connected to the LED. If it works, secure LED light leads onto craft stick with electrical tape. If it does not work try switching the position of the LED leads.



Here the switch is closed and the light on. Note that for this example we ended up using a yellow led we had laying around not the recommended bright white led.


The final flashlight with the battery and LED taped in place.



This is a slightly modified version using an ultra bright white LED and a cup with wax paper as a diffuser. Adding the cup and diffuser spreads out the light and makes shining it it in someone eyes less hazardous. This version also uses aluminum tape for the circuit connectors and switch.

Here's a video of the flashlight working during the day and in the dark:


Popular Posts

Tissue Paper Hot Air Balloon

Image
Perhaps you've seen hot air balloons for sale as science demonstrations/experiments that you fill up with hot air from a hair dryer and let float to the top of the room.  This product can be easily recreated on a smaller scale with tissue paper.  This project is a great way to demonstrate and learn about gases and density. You'll need: 5-6 sheets of tissue paper, a strip of paper, a glue stick, a marker, scissors, and  a hair dryer. The first step is to layer 5-6 sheets of tissue paper and fold them in half lengthwise. Use a marker to draw a half tear drop shape. Cut along the line and unfold the layers.  Each one will be a panel for the hot air balloon. Using a glue stick, or wet glue thinly applied with a paintbrush, glue one edge (marked in the picture above) and layer another panel on top. Pres down firmly to seal the edge. Once the glue has dried, unfold the two panels to inspect for any holes.  Make sure to seal up any gaps.
Read more

Cardboard Opaque Projector

Image
Update: (Please scroll down for step by step instructions of original Cardboard Opaque Projector) The updated Cardboard Opaque Projector is our attempt to increase the brightness of the light chamber inside the box and therefore the projected image.     A box that is 16 x 12 x 12 inches allowed us to position the light source below the mirror and closer to the bottom of the projector and therefore closer to the image to be projected. Adding black construction paper inside the lens barrel is to help image quality by reducing glare from reflected light inside the cardboard tube. Lining the inside of the box with aluminum foil and using a light bulb reflector shade with a 7W LED light provided substantially more light as well. Due to the size of the reflector shade we had to manuever it in place behind the mirror and then screw the light socket holder onto it through the hole in the back. This is tedious but not overly so. This shows the image to be projected and the projector on it's
Read more

Micro Automata

Image
Materials: • Wide clean plastic cup or clear solo cup. • A straw • Skewers • Bottle caps • Foam core • Tape Tools: • Scissors • Hot glue gun • A wood screw • Phillips screw driver or pencil Automata meaning self operating machine typically consisted of a clockwork statue or scene and were first created centuries ago in Europe and Asia.  They were in many ways the direct ancestor of what became electro mechanical robots.  For our purposes automata are a good way to explore machine's function of converting one form of energy and motion into another.  They are also a way to teach simple mechanical problem solving skills. Micro automata were the first in our series of attempts to simplify cardboard automata. The basic idea was to avoid building the box by putting the mechanism inside a clear plastic container.  Mechanically they are very simple. They have a input shaft with a crank coming out the side and an output shaft coming out the top with a mechanism in th
Read more