Best pratice to engrave mirror acrylic?

[Stroonzo (Jeff)]

You need to calibrate your laser PSU before any of the percentage of power settings make any sense.

Could this be a sign of a bad laser tube?

I am beginning to think you need to tune your laser PSU (as if the PSU is set too low). To do this, you need to know the highest mA draw specification for the laser tube longevity. A guess for an 80w tube may be somewhere in the upper 26 - 28 mA range (but you need to check to be sure). With this number in mind and with a mA meter on the machine (if you don’t already have an ammeter installled on the machine, they’re a pretty easy retro fit down stream of the laser tube) you can properly tune…