The laser diode in a handheld laser device decides the strength of the laser beam that is generated. You can build your own “cutting” laser with a couple of tools, a few common household items, and a laser diode purchased from a laser supply store. The most important part is to use a Blu-ray laser diode to generate the laser beam. The intensity of the Blu-ray laser diode will make your laser powerful enough to burn holes in paper and even cut through cardboard at close range.
Put the newspaper down on a table. Remove the battery cap and the batteries from the flashlight. Remove the reflector from the flashlight. Remove the reflector ring. Remove the reflector lens from inside of the reflector and toss it out. Unscrew the incandescent bulb from the flashlight and toss it out.
Unscrew the laser housing. Use the tweezers to pull the laser assembly out of the laser housing. Use the tweezers to replace the laser diode in the laser assembly with the Blu-ray laser diode. Toss the laser diode out.
Solder a conductive pin to the positive contact on the Blu-ray laser diode. Solder the other conductive pin to the negative contact on the Blu-ray laser diode. Let the solder cool.
Place the laser assembly back into the laser housing. Screw the laser housing back together. Put the laser housing into the flashlight, conductive pins first.
Drill a hole into the front of the reflector that is big enough for the laser housing to go through. Put the reflector ring back on the flashlight. Screw the reflector back onto the flashlight. Apply silicon paste around the inside of the reflector to hold the laser housing to the inside of the reflector. Let the silicon paste set.
Hold up the piece of cardboard. Aim the flashlight at the cardboard from a few inches away. Press the button on the flashlight to turn on the laser. Watch as the laser beam cuts a hole through the cardboard.
An alternative to purchasing the laser diode at a laser supply store is to remove the Blu-ray laser diode out of a low-cost standalone Blu-ray player or from a player that is broken.
A laser beam using a Blu-ray laser diode is dangerous to the human eye. Do not aim the flashlight that has a Blu-ray laser diode in it at a person. Using the laser you have built outside of your home could be a civil violation of the law.