[Rich] was having quite a bit of fun with his newly-acquired laser cutter, but was not impressed by the stock aiming laser that came with it. The problem with the built-in laser is that it did not actually follow the cutting laser’s path – instead, it has to be calibrated for a fixed focal length. This becomes problematic when engraving and cutting since they require different focal lengths, so it becomes a guessing game as to where the cutting laser will actually end up in respect to the aiming laser.
An additional optic module that solves this problem can be had for about $300, but after sinking $2500 into the laser setup, [Rich] was not inclined to purchase one. Instead, he bought a pair of cheap laser levels online and scavenged the line lens from one module, which was mounted on the laser cutter’s existing aiming laser. The second module was epoxied to the top of the cutting head, to create a set of cross hairs on the work surface.
As you can see in the video below, the hack works quite well, and the lasers are accurate at a variety of different focal lengths.