Engraving anodized aluminum

[Jetpilot67]

I'm new to engraving, but I want to attach a laser to my 3D printer to engrave anodized aluminum, black and other colors. What power and wavelength laser do you recommend?

[VDX]

... here some rough numbers -- black and dark colours can be engraved with 405nm-diodes with powers of 500mW and more, or with the 445nm-diodes with powers of above 1 Watt ... best with focal distances below 30mm and focus diameters below 0,1mm.

Viktor

[saara]

If it is 462nm instead of 450 it is maybe 36/8 W diode which will make it the brightest 462nm and since 462nm looks a bit brighter than 450 it means just 7% less apparent brightness than the NUBM44, so very interesting if this is the case.

[AnjinMeili]

I stuffed a bit of aluminum biz card stock up under my 445nm@5.5w module, and was surprised by the results. First one here is just a bitmap image that I ran at 300dpi, 100%, and 500mm/m. I focused my lens first using a spacer, and tightened it up using a USB microscope to gander at the dot.



This made me pretty curious, so I put together a material card and found I have some other issues with my PWM controller I believe. But that is another post really.. Test card uses 20 step @ 5% grayscale bars, each 50 or 100 mm/m apart.



In the second case, I changed from 0~100% for my grayscale range, to 25~100%. I also ran them both at .1mm or so, and that left some residue. There is also a fairly defined stair step pattern as the laser head got moving faster. So I would say go for it

Cheers
Anjin