Originally Posted by
robertk925
Do you have an ammeter (amp meter) on the machine? On my 50W blue and white Chinese eBay laser, 65% power equals about 20mA, which is the maximum (maybe even a little above) for the tube. Higher powers will eventually damage the tube and paradoxically often create less cutting power.
The very tip of the laser head should unscrew off, which will reveal the lens.
I would highly recommend searching for "SarbarMultimedia" on YouTube. Russ owns the same laser and has done a lot of experiments (and made a lot of helpful test fixtures) to better understand and fine-tune the machine.