Anodized issue's

[Scott Weinstein]

Hello all!

So I am working on marking some Anodized plates, a repeat job that usually goes fine, and am having an issue I have yet to encounter.

The mark seems to look good when completed, but when I go to clean the part, some of the image/marking actually rubs off the part.

Could this be an issue with the actual coating? Or is it pointing more to my machine? Seeing as it does not take a lot of power to mark on an anodized part I find it pretty odd that the white is just wiping away... photo(55).jpg

[Mark Sipes]

Have you tried to hit it again to see if the remaining material is removed.

[Mike Null]

Scott
I can't say I've ever seen anodized behave like that. It looks more like a screened surface--could that be?

[Scott Weinstein]

I have tried to make a second pass, and it looks a bit better, but I have not touched the mark as aggressively as I have in the image provided. I am not trying to reveal the bare metal as I am only trying to remove the color dye.

Screened? Not sure I follow Mike?

[Mark Sipes]

Not sure what make, model, size or power your machine is.

Maybe it is because I only have a 25 watt system, but I just hit a sample of black anodized at 100% power and a speed of 3 (of 100) and another at 100p 100s and they look identical...... so I guess I don't have to worry about cooking the aluminum to the point I remove any plating/oxide


How Aluminum is anodized and colored....... http://www.docsmachine.com/tech/anod.html

[Tim Bateson]

...Maybe it is because I only have a 25 watt system, but I just hit a sample of black anodized at 100% power and a speed of 3 (of 100) and another at 100p 100s and they look identical...... so I guess I don't have to worry about cooking the aluminum to the point I remove any plating/oxide...

WOW! That is Wayyyyyyyy too much power. Even with hard anodization I only use 75 power, but at 100% speed. There isn't that much difference between my 35 watt & your 25 watt machine.

[Dan Hintz]

Those strips look like bare metal.. I'm willing to bet you have stripped away the anodized layer altogether in those areas...

[Scott Weinstein]

Could this be a "Type 1" anodizing issue?

[Dan Hintz]

Could this be a "Type 1" anodizing issue?

Is it a Type 1 anodize?

[Gary Hair]

WOW! That is Wayyyyyyyy too much power. Even with hard anodization I only use 75 power, but at 100% speed. There isn't that much difference between my 35 watt & your 25 watt machine.

I agree. I have a 30 watt machine and run most anodized at 100% speed and around 80% power.

[Mark Sipes]

Thanks Tim and Gary ... What wattage and speed is Scott running on his machine when he engraves the problem material???

If you reread my post I was running a test of two extremes. I never said what settings I run anodized aluminum with. I was attempting to strip the coating off but with a 25w was unable. Maybe a 30-35w rips the coating off 100p 100s but I doubt it.

[Scott Weinstein]

Apparently this is a Type III anodizing.

60w machine.

Typically I run these at 120ips and 90pow. And usually do not have any issue.

What is weird is that if I use a towel and wipe the mark it seems like it is dulling the mark or taking off some of the anodizing (but not revealing the metal)

I have slowed down the machine to 60ips and 40pow and the mark looks good off the machine, but when I go to wipe the mark to clean the part it takes the contrast down.

[Mike Null]

What happens if you clean it before engraving? I've experienced some poor quality anodizing in the past.

[Michael Hunter]

but when I go to wipe the mark to clean the part it takes the contrast down.

Puzzled about the "cleaning" thing.
I love doing anodised, because there is absolutely NO cleanup to do afterwards.

If you get a white dust on the part, it is because you are damaging the anodised surface - try dropping the power until you get a bright white mark with no dust or residue at all.


My normal setting for black decorative anodising on my 60W machine is 75% speed, 22% power.
(This is "Epilog" speed scales, so 75% is pretty fast).