Looking at buying one. How deep will it engrave on aluminum and 17-4 stainless?
0mm, a diode laser of 20w won’t engrave at all, it’ll permanently mark the surface
A 60w diode can just about engrave/cut 0.2mm deep
To engrave and cut metals effectively you need a shorter wave length - ie: a Fiber laser
With the 20W module you will get the color engraving effect (tempering color) on stainless steel. It won’t engrave on aluminum unless it’s anodized aluminum. But either way, not really with a depth effect.
If you want to engrave plain aluminum the 2W IR module can do that, but also not with a depth effect.