A friend has a thing-o-matic 3d printer, and we where talking about attaching a laser for engraving, can you suggest what kind of laser is the ideal for doing that.
CO2 will definitely work with wood and plastic. A relatively small system will let you easily do this.
I don't think aluminum will work very well (not sure it absorbs well at 10.6um) - but if you're willing to invest in a cutting system at hundreds or thousands of watts, that would likely work. Someone who knows more about CO2 systems will have to chime in.
DO NOT put a co2 on one of those printers, unless you want it to destroy itself. the printer is made pretty much exclusively by things that absorb the co2 wavelength. you are pretty much limited to a 445 diode so you can cut out paper and maybe thin wood. (if you want to cut aluminum, you will need at least 100W)
it hasn't really be tested. 2 watts is alot. that is 3 times the rated value. but you might be able to get away with continuous duty if you put it in a good heat sink and used a tec.