After etching several dozen powder coated tumblers for various brands, I’m using the same settings for all brands and colors. My settings and cleanup process are revised slightly, but general guideline is the same, less power in this etching application is better than more power. Too much laser power tends to leave “laser tracks” on the stainless steel that do not clean off. This may be why some claim that 15W dual and 30W quad diode lasers can etch (using high power) onto bare stainless steel, no pre-coating necessary.
Updated etch settings for shinny stainless steel reveal:
Primary layer: Fill at 1000mm/min @ 25% power, overscan % as needed to achieve speed prior to etch, DPI interval is 67% (0.09mm) of my beam/dot width, CrossHatch Fill pattern (which accounts for an effective 2 passes), 0 deg scan angle, 1 pass, sharpest focus of beam.
SubLayer: Line, 1500mm/min @ 20%, 1 pass. This is a shape outline to burn off any jagged shape edge left from the raster scanning. Use a little outer Kerf Offset on this if you want to.
You can scale these speeds and power if your machine is capable to run faster, I’ve gotten mine faster but I found the power scaling in my machine’s case is not linear to speed for this type of etching. Rather, I found that 6000mm/min @ 75% power CrossHatch scanning was sufficient. I also setup LBs Scanning Offset Adjustment table for speeds over 1000mm/min.
The cleanup process change uses Dawn liquid soap and water with a Magic Eraser pad brief scrub, seems to be as good or better than LA’s Totally Awesome stuff and Bar Keepers Friend.
Key point remains… Less (power) is more in this case for shinny stainless steel reveal.