Black Hard Coat anodized aluminum

I have a gun part a friend wants me to test on and see if I can etch it or remove the black covering the aluminum. Its black hard coat anodized aluminum has anyone done this and if so what is the best settings?

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Dis you search for “anodized settings” or “engraving aluminum settings”?

I’m not sure anyone specifically called out “hard coat anodizing”, but I’m not sure if that refers to a specific type of anodization.

There are lots of anodized aluminum engraving success stories on the forum, a little searching will find what you’re looking for.

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You can’t remove the anodizing to my knowledge. The laser ablates the dye that is added after the anodize is completed, but leaves the anodized coating in place. I think you will need a higher power laser than 45 W to remove the anodize layer.
If you just want to mark the part, you can use the laser to selectively ablate the dye to reveal the silver aluminum.

the anodizing on gun parts is typically much thicker than what you would find on anodized aluminum blanks ( like dog tags or business cards). Expect to use multiple passes.

We had a coating at Beechcraft for aluminum parts used in the airplanes. It was applied by the chrome division, since it was a similar process as chrome plating.
It made those aluminum parts incredibly hard, while still maintaining the light weight needed for aircraft.
If this is the same process, you would have to grind it off to get to the aluminum underneath. A file on it was like trying to file a coke bottle.

Worth sticking it under a laser I suppose, to see how it reacts, but if it is the same process, I am willing to bet it will not damage it.

Keep us informed. I, for one, would be interested if it can be marked.

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I bet this is just a thick hard anodize. I have seen hard anodize parts that feel the same way with a file, you have to really push hard to get the teeth to bite. If it is anodize, the dye should ablate.

It might also be an electroless nickel though they usually don’t like putting that on aluminum because the softer substrate can cause the plating to crack under stress.

This is what I wanted to do sorry I didnt properly state it I just want to show silver.

Look for the settings others have used for the aluminum plates as your start point.

It’s called “Engrave” in the user interface no matter what material you’re working with, so don’t worry about it! :slight_smile:

You can’t remove the anodizing to my knowledge. The laser ablates the dye that is added after the anodize is completed, but leaves the anodized coating in place.

Anodization is increasing the thickness of an oxide layer. If you add dye, it gets colored too. So I think when you blast it with a laser you are removing the oxide layer.

In this closeup of some engraved anodized Aluminum, you can see that material is actually being removed, it’s not just recoloring the anodization. If you run your fingernail across the letters, you can feel the ridge.

I guess it depends on the settings:

Huh. Doesn’t seem to be what happened with my parts. I will have to put some engraved Aluminum under a scope and check it more carefully!


Turned out rather well.


One of my friends needed to do something similar - what settings did you end up using?

Full, 200, … I set it to 3 passes because I was not sure if it was going to go through. It would have probably been fine at 1 pass 2 to make sure it was 100 percent clear.

This turned out great. Im actually looking to do the same exact thing on the same part.
full power, 200 LPI with 3 passes were your settings?

I’ll be engraving an American Flag so I need the detail of the stars to be crisp

The 200 is likely the Speed. Use the highest LPI on coated aluminum and you can leave it at one pass. (Gives better results to use High LPI on coated metals.)