Marking aluminum with a C02 laser

[Robert L Stewart]

Hi all,

From what I read here it takes takes a fiber laser to mark metal unless one uses Cermark. What about marking
raw aluminum? Can it be done with a C02 laser and what wattage would it need to be? Another question is what wattage would be needed to cut 18 to 20 gauge steel?

I have a client that needs to have 50 pcs (these will fit in a epilog mini) done with a small logo.


Robert

[Lucy Lee]

seems CO2 can't work on the raw aluminum,



Hi all,

From what I read here it takes takes a fiber laser to mark metal unless one uses Cermark. What about marking
raw aluminum? Can it be done with a C02 laser and what wattage would it need to be? Another question is what wattage would be needed to cut 18 to 20 gauge steel?

I have a client that needs to have 50 pcs (these will fit in a epilog mini) done with a small logo. Is there any one in the San Diego interested in doing this?



Robert

[Dan Hintz]

Robert,

You cannot mark raw aluminum without Cermark (or similar marking fluids). You can get a really nice white mark on anodized aluminum (clear anodizing notwithstanding, and silver anodized has a very low contrast for obvious reasons).

You will not be cutting steel with a CO2 unless you bump up the power to 150-200W+ and add oxygen (and don't expect the cut to be high quality)... otherwise, expect a kW-level laser to do the job.

On a side note, I would remove your request for someone to do this as it will force the thread to get moved to the Classifieds section.

[Mike S White]

Robert you can Mark certain types of steel such as stainless directly using a CO2 laser. It requires 50+ watts & very High density optics to achieve this. Universal offers there HPDFO that will do the Trick but not sure if other manufactures have something similar. http://www.ulsinc.com/products/features/hpdfo/

As far as marking Raw Aluminum I have had Good luck Using Thermark LMM14. Below are 2 pieces of raw aluminum marked using Thermark. One thing that Should be Noted is that Thermark / Cermark Marking are NOT UV STABLE so they are not really suitable for outdoor use.
274458 274459

[Michael Hunter]

A few years back someone posted a photo of raw aluminium engraved with a CO2 and showing lots of different colours using the plaster-of-paris method.
Apparently different powers gave different colours.

When I tried it, I had no luck at all, but the aluminium I was playing with was extremely hard (maybe even dural), rather than the half-hard stuff one generally finds.

[Dan Hintz]

One thing that Should be Noted is that Thermark / Cermark Marking are NOT UV STABLE so they are not really suitable for outdoor use.

There should be no issues with UV stability of the Cermark itself, it's the substrate that you have to worry about. Cermark is no less durable than any enameling done... in fact, Ferro has a video where they bring a turbo up to cherry red hot with no ill effect on the mark.

Robert, be aware if you do go with the HPDFO (or similar) option for marking SS directly, be prepared to go reeeaaaalllll sloooooowwwwwww. Compared to a regular run like anoidzed aluminum, it's like watching paint dry.

[Kev Williams]

I don't know about Cermark other than the LMM6000 stuff I use on SS, but I've never had any UV issues with it. I've always assumed that since it's ceramic based, it should be as UV stable as a coffee cup!

[Mike Null]

I've had good luck with Cermark and outdoor applications. I have never had any luck with Cermark and aluminum but I can engrave directly on ss with my 45 watt and a 2" lens. It's slow but doable.

[Mike S White]

Thermark Will handle up to 1800F no problem. See here http://www.thermark.com/content/view/48/87/

And I guess I should have specified UV stable.
It will be Fine outdoors for about a Year after that it will start to fade. Don't expect it to last 10 Years outdoors in the sun like a Permanent mark would.

And Dan is Correct on the HPDFO slow but not to bad if your doing small parts.

[Dave Sheldrake]

HPDFO units can be made using a beam expander and your current set up, like all the guys say though, it doesn't actually increase power per-se, it just focusses it onto a smaller spot giving higher power density (above the threshold for marking some metals).

cheers

Dave

[Dan Hintz]

And I guess I should have specified UV stable.
It will be Fine outdoors for about a Year after that it will start to fade. Don't expect it to last 10 Years outdoors in the sun like a Permanent mark would.

I seem to recall some threads here (and elsewhere) stating numerous years in the elements without a problem. Cermark is a pigment (metal oxides) held within a glass matrix, not an organic dye, so UV stability shouldn't be a problem.

[Robert L Stewart]

Dan, Thanks for that info. I was thinking along those lines. I believe I will pass on this project.
Mike, Thanks for deleting my last request. Will make sure to use the classified section in the future.

Thanks to all.

Robert

[Chuck Stone]

I seem to recall some threads here (and elsewhere) stating numerous years in the elements without a problem. Cermark is a pigment (metal oxides) held within a glass matrix, not an organic dye, so UV stability shouldn't be a problem.

I'm not sure why, but when I did a pen with Cermark (think it was 6062 aluminum) it looked great
for about 8-10 months and then faded to gray. It wasn't even in direct sunlight, but the side facing
up faded more than the other side.

[Mike Null]

But that may well have been an application issue.

[Chuck Stone]

But that may well have been an application issue.

How so? Not sure I understand.
And .. if it went on looking correct, marked well and looked good.. how is one
to know if there was an application issue? Certainly we can't hold customer's
goods for 10 months to find out .. if we did, we'd have to call ourselves Cobblers
and tell everyone "It'll be ready on Friday"

[Mike Null]

Chuck

When I've had a problem like you described it usually reveals itself almost instantly with hard rubbing with a cloth. In that case I re-do the piece or replace it entirely. I'm only suggesting that it's possible the application wasn't good but went undetected, possibly due to lack of handling.

I've made many, many ss asset id tags for outdoor use and have never had a complaint but I check them all during the clean up process.

As I said earlier, I've never discovered the secret to doing aluminum with Cermark.

[Chuck Stone]

Hmm .. it was handled. First thing I do with a piece is take it to the sink and
hit it with a scrub pad to check. Early on, I had application issues and the mark
would come off when handling. So checking that is routine now.
No.. this was a solid mark. It's still well stuck, it's just bone gray.

[Keith Winter]

Robert you can Mark certain types of steel such as stainless directly using a CO2 laser. It requires 50+ watts & very High density optics to achieve this. Universal offers there HPDFO that will do the Trick but not sure if other manufactures have something similar. http://www.ulsinc.com/products/features/hpdfo/

As far as marking Raw Aluminum I have had Good luck Using Thermark LMM14. Below are 2 pieces of raw aluminum marked using Thermark. One thing that Should be Noted is that Thermark / Cermark Marking are NOT UV STABLE so they are not really suitable for outdoor use.
274458 274459


Looks great Mike! :)