Laser Engraving still not perfect

I have been trying to engrave yeti mugs but can’t quite perfect it. My goal is to just remove the powder coat layer to expose a shiny stainless steel layer.

Here are all of my test attempts (0.1mm fill was used for all):

# Work Speed (mm/min) Laser Power Distance from Obj Note
15 500 30% / 20% 10mm Changed to 20% power partway through.
16 400 20% 10mm Changed workspeed to 320, 240, then 160. Got progressively darker. Must have been burning the stainless steel.
17 500-600-700 20% 10mm Used Cermark spray. Hit 500, 600, 700mm/min.
18 1500-750 16% 10mm Started @ 1500. Changed to 750mm halfway thru. 1500 was too fast, still some red
19 375 16% 10mm Still very gray
20 500 16% 8mm Changed to 250mm speed 1/2 way thru. Changed laser power to 25% at very end.

I am getting close but not quite there. I have been using a focal distance of 10mm since that is what is recommended by Snapmaker but maybe the laser is not in focus? I can’t tell if I should change laser power, workspeed, or focal distance.

Any help would be greatly appreciated.

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Hi Bijan, I’ve actually had some luck with stainless steel knives.
First attempt at Stainless Steel Knives Then again, I wasn’t trying to remove a powder coat. Not a clue on that one (yet… I do have a mugs I’ll eventually practice with)

Here are some others I’ve since done. The trick seems to be in the laser spray paint.


I used the marking spray for #17 but it did not make a difference.

Just did a quick search for a 10 watt diode laser removing powder coat. I didn’t find a single hit on the web. In the new world of AI, that says a lot. Lots of fiber, some CO2 and Endurance has a passing mention but the only thing I found with 10 watt diode is adding powder coat rather than removing it. While I’m not even sure if what you are trying will work, I’m thinking focus would be where I experiment first.

The burning always leaves a residue. The trick is finding the balance where it removes the residue but doesn’t permanently mark or darken the metal. Different colors will often need different settings since they absorb the laser power differently

Have you tried using a mr. clean magic eraser and/or acetone to remove the residue (do a test in an inconspicuous area to make sure you aren’t removing the coating also). Super fine (0000) steel wool can also help, but might affect the yeti’s finish.

You shouldn’t be using marking spray (or dry moly) unless you’re trying to darken the metal.

-S

I wipe the laser residue with LA Awesome cleaner and a magic eraser. Everything you see is what is left after I do this.

I used Dot filled at .14 infill and 55% laser power.
You really need to buff it out with magic eraser and maybe some barkeepers friend

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  1. What was your dwell time?
  2. You used the rotary with it?
  3. Did you use the calibration card (the thicker one)?
  4. Did you leave the laser at the standard height (~10mm) after you touch the laser to bottle?

What speed?
You’re only sharing half of the applicable settings.

-S

Dot filled and infill settings affect image quailty. Dwell time, speed and for the most part, laser strength all depend on the type and thickness of the material covering the cup. You will have to experiment with what works best for you. I started with the defaults and adjusted the laser power until I got the results I wanted. If I had hit 100% and still did not have what I was looking for, I would have adjusted the speed next as speed and dwell time affect the over all time it takes to print, I would adjust those last.

My point was, no matter what, you are going to have to buff out the cup to remove the residue.

I used the rotary module, set laser height with the THIN .1 calibration card after having gone through all the other calibration steps outlined in the user guide. Everything else was left at default.

Keep it simple and only adjust what you need. Adjust one setting at a time until you get the desired results

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