help with aluminum

[Bryan Pierce]

I am fairly new to laser engraving. I have been reading this forum for almost a year now, and have found the answers to all of my questions, but need help with this one.
I have a customer that is looking for aluminum id plates with a black background and red and white text. What are my options? He needs 500 to 1000 and is only interested in aluminum.

[Dan Hintz]

The triple color is a bit of a problem. If money were no object, I would use black anodized plates, engrave the red letters, re-anoidze for red, then mask for white, engrave the white letters, and use an automotive paint. but that's an extremely long process and won't be cost-effective for anyone but Bill Gates.

Is the client willing to drop down to just two colors?

Another option is to use dye-sub...

[Dee Gallo]

Brian,

I had some luck using automotive primer (red, black, white) under regular auto paint. The laser will not go through the primer, just expose it. So if you paint the primers in the right places, you could do the job in one pass.

Might worth an experiment for you.

cheers, dee

[Mike Null]

You could use dye sublimation but that is neither a cheap nor efficient way to go. Given the equipment you are listing you have no choice but to outsource the job.

If, by chance, the red portion happens to be the same on every piece then you can have the anodized labels cut and screen printed then you can laser them in house. You can also get anodized foil labels printed then you can engrave.

[Dee Gallo]

Here is a pretty ugly photo of my first test, but it will give you an idea of how you can paint several areas underneath and then over coat with something else.

Here, you see no primer on the bottom left, white primer on the bottom center, red primer on the bottom right and black primer on the top 1/4. Topcoat, black on top, blue on bottom. Obviously, the black-black was not a good combo - should have painted the bottom half black and the top blue, but.. The percentages you see are power (100% at the bottom).

~ dee

[Bryan Pierce]

Thanks for the quick reply. Thats what i was afraid of. I do have a heat press, and i am thinking about a dye sub printer, but wouldn't be cost effective for this job.

[Bryan Pierce]

I like that Dee i will keep that in mind for future projects. Dan - He said he would be alright with 2 colors. It is his company logo and i hate to change it, but looks like i don't have much choice unless i outsource it.

[Rangarajan Saravana kumar]

Dye sub makes quick, less problem

Regards

Saravana kumar

[Rodne Gold]

Black anodised will laser white , and you can actually colour the white text that needs to be red with dyes/paint as the laser leaches the dye and the sealing coating and thus the engraving can be re coloured.

[Mike Null]

Rodney

Got any samples to show?

[Rodne Gold]

No samples to show mike , I last did one this way many years ago. If I get a chance , will do one and take a pic. I used a dye on it.
I used to anodise all my small car parts in a bucket using some diltute battery acid and a battery charger , dipped in warm to hot various coloured food dyes or other dyes after anodising to give it the colour and then boiled the piece to seal it.

[Mike Null]

My concern was that the remaining anodized surface would also be colored and not be a pure black. Does that happen?

[Tony Lenkic]

Bryan - Is your client specific on thickness of aluminum? JDS has 0.025" P/N ALUM395 (black lasers white)
You can laser and shear them to final size than have logo screen or pad printed (assuming logo is to be red).

[Bryan Pierce]

I did a sample for the customer with black anodized aluminum (.025). I was wondering if i could engrave the piece then mask all but what needs to be red and paint. Not sure how that would look.
Tony - the logo is the red part so that is an option.

[Richard Rumancik]

Black anodised will laser white , and you can actually colour the white text that needs to be red with dyes/paint as the laser leaches the dye and the sealing coating and thus the engraving can be re coloured.

What Rodne is describing sounds like the process Peter Laakmann (the founder of Synrad) tried to develop. He claimed that after lasering anodized aluminum, the surface would again become receptive to organic dyes. His method was to use organic dyes (i.e. felt-tipped marking pens) to recolor the exposed alumimum. I have not really seen it promoted a whole lot; I have a copy of an article from "The Fabricator" dated 1992 which he wrote explaining his process. It is an easier read than his patent. It might be worth trying a quick test.

Basically, take black anodized aluminum, laser all the graphics, (red and white), then isolate the red logo area and see if you can make it accept a red dye. The water-based dye should just bead up on the black anodize and can be wiped off. You can use multiple dye colors, but you can't have two colors touching with this process as they will likely bleed together.

Laakmann claimed that you can re-seal the pores by immersing in 90 C water after coloring.

Note that the "white" you get will not be a brilliant white but a matte off-white to silver gray.

It looks like a neat process but I can't comment on the efficacy, as I have not tried it myself.

If anyone wants a copy of the article I could scan it and send a pdf.

[Tim Bateson]

If you don't have a Dye-Sub, but do have a press... just use either your laser/inkjet printers. They each use different papers, but I have had some good luck experimenting on anodized tags. I have a couple on my key chain going on 4 months now as a test.

[Rodne Gold]

Basically , we do what Richard describes to colour it, The black doesn't stain , but I suppose that depends on how the anodising plant has sealed the anodising , there was another way of sealing other than boiling , I think it was using amonium perchlorate or something like that , here's a nice sort of article (albeit it seems to be commercial) on the process I used to anodise
http://www.focuser.com/anodize.html

[Dan Hintz]

Ugh, don't know how I missed it... Rodney's right, the black will laser white, so there's your third color. So back to my original sequence, but instead of masking for white, just laser. You can do a final boil seal on the white, if you wish.

One caveat... your black anodizing must be top notch if you want it to turn white. A mediocre or poor job will laser gray or putty colored.

[Dee Gallo]

Well, you guys made me do an experiment. I took a Chewbarka tag that I'd never need and ran a test word and image as normal. Then, I took a red, blue and green permanent marker (Sharpy) and colored in letters. Then, I used a highlighter (pink Scripto) (the E is plain) and colored in the image. This picture shows what it looked like.

I then cleaned it in boiling water and scrubbed it with a toothbrush. The pink (less dense pigment) came off a little, but the other colors stayed the same. Any marker that got onto the black came off, such as the haze you see around the blue.

Thanks for the inspiration!

cheers, dee

[Mike Null]

Dee

Doggonit! You shouldn't have done that---there are some things I don't need to know.;)

Did you test with dna?

[Dan Hintz]

Mike,

Other than the slight fading with the red Dee saw, it's a pretty permanent solution. Once you lock it in with the boil, it's (almost) as good as any standard anodizing... definitely not noticeable on small items. I must be slipping in my old age, as I didn't suggest it myself (again).

[Dee Gallo]

Okay, Mike, I went at it with some DNA and it did get slightly lighter/brighter but stayed colored. But the pink is completely gone now.

Are you happy now?

:) dee

edit: I didn't boil it long, just a half a minute..maybe a longer boil would change things.

further edit: I decided to try adding more color to the design which lost its color. I used the permanent markers, red in the center and blue on the outer edges, then blended them to the middle purple. Boiled it again for a full minute and a half this time and scrubbed with alcohol again... the color remained the same.

[Craig Matheny]

Richard could you scan the article and post as a pdf then it will be here forever and a day and you won't get a lot of emails.
Thanks

[Richard Rumancik]

I would post the pdf, but it is 666 Kb so it is too large to upload as an attachment. Or is there some place I can park it at Sawmill Creek? If not I'll email it to anyone who supplies an email address as I can't send it via PM either.

[Richard Rumancik]

Dee, if you were unable to remove the Sharpie with DNA then you must have done a good job of sealing the anodize. Sharpie ink is an alcohol-based ink, so if alcohol did not remove it then it is sealed in. The highlighter ink is more than likely a water-based ink. That is not to say you can't use water-based dyes on anodize - I believe many commercial dyes are water-based -but results may vary depending on the chemistry of the dye/ink. The alcohol based inks are less likely to be affected by the hot water.

[Dee Gallo]

Rich, thanks for the instructions on doing that - I will definitely being using this in the future. I love making anodized stuff, so clean and easy. This color thing adds dimension. I used a small amount of water with the piece in it, placed in a microwave and it boiled quickly. I thought the water-based marker would come off in the water bath and it did somewhat. Permanent markers come in zillions of coors, so there are loads of applications for this procedure. The ones with fine tips make it very easy to apply. I don't know if I'd want to do hundreds of them, but it really wouldn't be horrible... I'm good with tedious.

My next thing will be to locate my no-color marker which is used for blending.

cheers, dee

[Dan Hintz]

Richard,

I evidently missed your post (last one on the first page)... I'd be interested in perusing that article, too. I never realized someone patented the idea, but I've seen it on the net a few times.

[Mike Null]

Dee

Thanks for your efforts. I don't know that I'll use it but still it's good info.

[Gary and Jessica Houghton]

Dee,
You have inspired me. I so need to try this! I have too many customers asking about colors I cannot produce. This seems easy enough for even me to try.
Jessica

[bryan henderson]

I have tags that are already stamped and have two 1/8" diameter rivets holes in them. I use them for production job and when laser engraved the area becomes white. Are you still looking for some???

[Mike Null]

Bryan

Don't know if you intended to run an ad here but that is not permitted. All ads must be placed in the Classified forum and by contributors.

[Tim Bateson]

Here are my test pieces -also Chewbarka Anodized tags. A $99 Laser Printer, Cactus transfer paper (not recommended), & a simple Heat Press.
After about 4 months, the larger eagle tag hasn't held up as well - I experimented with a lacquer finish - don't bother.

[Richard Rumancik]

Just an aside - Horizons ISG has a few products that incorporate the idea of applying color to unsealed anodized aluminum. This does not involve the use of a laser engraver, however.

For example this page

http://www.horizonsisg.com/durajet.html

shows their Durajet product. It is basically unsealed anodize to which color is applied using inkjet. Then the color is sealed in with a boiling water/chemical solution.

As far as the Laakmann concept of using the laser to open the pores on previously sealed anodized aluminum - I have found very little on the Internet about the process or why it even works. Apparently there are some chemicals that can be applied to re-open pores after sealing, but Laakmann's concept was predicated on the application of the laser to re-open the pores. I haven't really found any independent research on this.

[Dan Hintz]

As far as the Laakmann concept of using the laser to open the pores on previously sealed anodized aluminum - I have found very little on the Internet about the process or why it even works. Apparently there are some chemicals that can be applied to re-open pores after sealing, but Laakmann's concept was predicated on the application of the laser to re-open the pores. I haven't really found any independent research on this.
Richard,

You're basically boiling the water from the aluminum oxide layer (hydrated)... this opens up pores, in a manner of speaking, which can then accept dyes. No reason a chemical wash couldn't also be used...

[bryan henderson]

I completely understand the rules within SMC, I am just throwing it out there to help or aid fellow Creeker, that is all really.

Bryan