I'm having some issues engraving powdercoat over stainless reliably. I understand the vast potential differences in color, thickness, quality, etc. I'm mostly just curious if others have run into the same walls as me, and if they found a workaround.
From the attached photos its clear that I have the settings for red and white mostly dialed in. The only issue I'm still having is the slight lines in the direction of the laser travel. My big problem is the blue. I have read that blue is always a major pain, but dang, I wouldn't think it would be this tough. I can get through the coating, but at the power settings needed to remove the coating I am leaving burn marks on the stainless (ironic).
I have found that the following settings seem to work well:
- Ozark trail coated water bottles, blue, red, and matte white
-100w CO2 chinese laser
Red and white -- 19 watts power, 300mm/s travel, 0.03mm scan, 0.05" out of focus. Final wipe down with clorox wipes.
Blue -- 24 watts, 300mm/s travel, 0.03mm scan, 0.05" out of focus. Leaves the linear burn marks in the direction of laser travel.
22 watts, 300mm/s travel, 0.03mm scan, 0.05" out of focus. Leaves minor burn marks and some blue haze remains in the small details. Xylol to remove.
20 watts, 300mm/s travel, 0.03mm scan, 0.05" out of focus. Leaves a blue haze, Xylol will remove most of the haze but dulls the finish of the remaining coating.
I have tried so many different variations of speed, power, scan and focus I am going crazy. The above settings seem to work the best, but aren't even close to acceptable.
So, a few questions:
1.) How to stop the burning?
2.) How to get rid of the faint lines? (I'm guessing 1 & 2 are related)
3.) Why does everyone refer to power settings as percent instead of watts? Everyone has different wattage machines, % doesn't seem to relate. Power stated in watts is universal, isn't it?
Photos are here. http://mylocalmaker.com/photo-drop
Thanks,
Shannon