Cermark on Light Colored Anodized Aluminum ?

[JB Lynn]

Hello :

We're having a dilemma raster engraving silver and gold 'anodized' aluminum. We've coated it with Cermark LM-6000 and continue to get a whitish raster impression? Isn't this product supposed to produce a black image on anodized aluminum? BTW, I am using a 35+/- Watt machine that does a beautiful job with Cermark when it's used on Stainless Steel at 100% Power/9-10% Speed. Also, our question ONLY relates to gold/silver aluminum, naturally we get a white and very desirable raster with red, blue, black etc. anodized aluminum.

Thanks in advance for your help or advice,

Regards, JB Lynn

[Mike Mackenzie]

JB,

Cerdec is not useful on Coated metals only on un Coated. Clear anodized or any anodized metal has a coating. The white you see is what anodized metals will look like when lasered.

Now saying all of that Ferro the makers of cerdec have made some cerdec that works on clear anodized metals. I don't know if it is a product for sale or if its still in the testing stage.

[Rodne Gold]

You can try this: Dont use cerdec , apply a paper based vinyl application tape , laser thru this into the anodised ally , then before removing the mask , colour in the engraving with a permanent marker.
Anodising is actually porous , I used to anodise my car parts in a plastic bucket , some dilute battery acid and a battery charger and then dip it in warm food dyes to make it any colour I wanted - boiled to seal it after. (some are still vibrant and fade free 8 years on - some have faded , depends on dyes)
What the laser does is remove any sealing of the anodised layer and leaches the dyes used to make it coloured. The layer is now porous and the ink from the marker soaks in. The mask is to stop the unlasered anodising staining (often not sealed well)
You can do various colours with various paints/inks etc.

[JB Lynn]

Hi Rodne

Thanks for the tips...you always have such great insights into so many laser subjects

OK, we have a 35 Watt Laser (it was measured as 37.5). I tried the masking approach but no matter how powerful/slow I go, I end up with a sticky area where the paper tape was burnt off.

As an alternate, I decided to do a slower/more powerful raster burn on 'unmasked' silver anodized aluminum to create a porous raster image; after doing this, I filled in the raster image with a 'Sharpie' permanent marker and Let it 'soak' in for about 10 minutes and then used alcohol to clean-up the marker on the sealed areas. The impression seemed a shade too faint. What can be done to make it darker and VERY permanent? You mentioned 'boiling' would this help? Should it be done before or after cleaning up the excess? Is 35 Watt sufficient to create an absorbent and porous image on silver or gold anodized? Also, is there a particular ink that is better for soaking into the aluminum?

This will open MANY opportunities for us if we can produce color on silver/gold anodized

Thanks again for ANY help you can give? JB Lynn

[Pete Simmons]

I just tried this on Brass with a 35 watt Epilog. speed 40 power 70.

Used Laser Bits paper masking tape, filled with a magic marker and removed the mask. Looks pretty good. I am still going to look into the Cerdec. I wrote them to see why brass has a * next to it. I cannot find what they are referencing with the *. I have heard that the brass transmits the heat away to quickily and makes it difficult to work.

[Rodne Gold]

Im not sure why you are ending up with the stcky bits , it might be the adhesives on the premask you are using , doesnt happen with ours , but I couldnt tell you which type we use , we get it from our vinyl supplier.
A lot of how the ally accepts inks and paints depends on the anodising.
If you arent getting a good result with a sharppie , try a spray paint.
This does work for us , but as you say , the mark never becomes a deep black at all iunless we use a paint. Boiling is a way of sealing after , but bear in mind , when I did this to my car bits , I was dyeing totally unsealed anodising.

My biggest problem with this method is the fact that the unengraved anodising does sometimes stain.

[Rodne Gold]

Just as an aside , we hardly do this anymore cos we have a direct printer that can print up to a 1440 dpi full colour image on anodised ally (its not a sublimation printer - its a small flatbed and can print 490 x 360mm size) and the print *is* a deep black and can be full photographic. Its a huge amount quicker than a laser (full a4 in 2-3 mins) , can print on curved surfaces and can accpet anything up to 4" thick.
It basically can print on just about anything , tho some stuff must be coated with ink receptive coatings.
The durability on anodised ally is amazing and so is the pop etc.
The machine is called a Busjet pro 603. I have wrritten about it here
http://www.dyesub.org/forum/?msg=2517.1

[Peter Vasic]

Try this,


Im not sure if it will work for you, but.

get a scrap piece of the anodised aluminium you are using.. square it up in your machine, engrave it as you normally would, brush some cerdec in the same spot.( dont move your piece of ally ) wait til it dries, hit the send button again and see what happens....

Let me know if it works..

regards

Peter

[Darren coffell]

we work on a lot of clear anodized aluminum. we do exactly that. we lazer first at a low power around 25% power 100 speed. then we clean the area with a good solvent degreaser and alcohol, spray the cerdec, let dry then laser with 100% power 25 speed. most of the time the coloring is very good so long as the anodizing was done correctly.