[Drake Anthony] makes building a cutting laser from a PC look easy, and it seems like it actually is. Almost everything you need can be found in a dead desktop unit. The diode is pulled from a DVD writer (16x or faster), with the power supply unit, and heat sinks from the processor and GPU being used as well. You’ll also need a focusing lens (just a few dollars), some thermal glue, an LM317, a resistor, and a pair of protective goggles matching the laser diode’s wavelength.
He fits the diode into the lens, then glues the assembly into a hole drilled through the processor heat sink. A driver is built using the LM317 variable regulator, resistor, power supply, and the GPU heat sink to keep things cool. Check out the video after the break to see the laser cutting tape, burning plastic, and lighting matches.