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Any good Anodizers - Worldwide?

Joined
Nov 26, 2018
Messages
79
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56
#1
Hi to all,
For years I am looking for good anodizers.
I have learned a lot about aluminium alloys during the process,
and in Germany where I live I have tried about a dozen of anodizers,
scattered over the whole country. But almost none of them were able to finish
the surface of my samples like we are accustomed to from our everyday goods like
HiFi, Laptops, objective lenses, smartphones etc.
Most of the samples I tried were dull or had stains,
although the alloy was certificated for decorative anodizing.
Not the silky surface we know for sure, no matter if bead blasted or brushed.
Brushing once was an apprenticeship, this is not done any more, so no one is able to
brush a straight hairline - besides robots that brush parts during mass production.

BTW, this blog of John Seaber from JDS, who makes the OL DAC and EL DAC has my problems a well:

https://blog.jdslabs.com/2013/05/how-to-finish-aluminum/

To give you an idea on how low the standards are:
One anodizer stated the lid of my Macbook, -presented to him as reference for the final look- was made of plastic.
He could not believe the fine silky and scratchless surface was anodized aluminium.
Another anodizer fronm another company was presented a brushed deep black Nakamichi frontpanel.
He insisted the deep black was laquer (like carpaint) what is wrong.
Reason was the deepest black the company could produce with anodizing
was still a dull, dark grey. Dyeing during anodizing is adifferent process than painting.
The metal get porous at one point and sucks the colour like cloth does.

Another Company that has High End Audio manufacturers as customers spoiled the brushing and
colourization as well.
So besides the fact that is very hard to find anodizers who are capable to produce glossy surfaces,
- through bright dipping - it is almost impossible to find one who has the willingness and spirit to take care for detail or thorough quality control.
All anodizers I tried just throw your single part into their bath without adjusting parameters.
I am also sure that none of them gave the parts a glance once they were finished. It is really a mess.
Long Story short:
I put a lot of work into my last design and willing to travel the world for a good result.
This is an international forum, so:

Any tips?

All the best,
Herbert
 
Joined
Apr 11, 2019
Messages
5
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1
#2
To have Mac finished it needs to be glass bead blasted. Of course, using the right alloy also helps for the finishing.

I can check the company that my company uses in Switzerland (since it is close), I've had 5 samples tested for colour and they had excellent finishing
 
Joined
Aug 11, 2019
Messages
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Location
US East
#4
Apple invests heavily on R&D on surface/cosmetic finishing of their products (which includes anodization). A quick US patent search on "anodizing" shows 3 Apple patents. If you look into the reference sections of these patents, you will find many more additional Apple patents.
https://patents.justia.com/patents-by-us-classification/205/324

Look and feel is Apple's bread and butter, and they don't take any chances. Their technology is absolutely state-of-the-art and they protect it with patents. It is definitely too much to expect a random shop to match what Apple can do.
 
Joined
Nov 26, 2018
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#5
Hello mvil,
thanks a lot. Stalder was not on my list. They also do bright dipping. (Chemisch Glänzen) But it looks like they do not bead blasting,
at least not in house, which might be problematic,

@NTK
I never understood these Apple patents. What they are writing is not new at all and it is also not state of the art.
It is just mass processing with extremely tight parameters . With their patents it always feels like they are hopping
into gaps others left to claim a patent for . Also remember companies like Nakamichi, Onkyo or Accuphase who had suppliers
that were able to anodize the deepest and glossiest blacks.

If you want decorative surfaces, shiny / silk / brushed steel like surfaces you are limited to three alloys,
5754 (AlMg3) / 5083 (AlMg5) and 6060 (AlMgSi0.5) .
6060 yields the best results and is still relatively shiny, but is only available for extrusion.
Thick plates of 6060 can also alter in stucture. Not visible to the eye but colour can change after anodising.
You cannot mill 6060 as well as 5083 anyway, it "smears"
So for CNC-milling (besides the many alloys which are not suitable for decorative anodizing)
only AlMg3 (5754) and AlMg5 (5083) are suited but are much duller after anodizing than 6060 and need bright dipping.

The problems I had so far was not that the process is state of the art but that anodisers were not willing
to take the extra time for processing.
One example:
For the mandatory cleaning of grease and stripping of the natural oxide layer you should 5083 dip into Acid
just for seconds or better avoid it. This acid pre-treatment makes 5083 too dull. 6060 is more tolerable with that.

90% of the anodisers I tried obviously treated my 5083 samples with acid like 6060 to make sure
grease / dirt is whashed off without effort. As a result what I got back was dull sh*t with the look and feel
of light grey sandpaper.
Just one got it right but his wheel blasting machines for bead blasting are too small for my parts and he does not blast by hand.
Another one got them shiny but was bad at blasting. The media for blasting was contaminated with bigger chips
so I got little craters.
A supplier for aluminium once tested anodisers using front men and got bad results, though the manufacturers
offer white papers on correct anodising treatment...
 

LTig

Senior Member
Joined
Feb 27, 2019
Messages
467
Likes
537
Location
Europe
#6
For years I am looking for good anodizers.
I have learned a lot about aluminium alloys during the process,
and in Germany where I live I have tried about a dozen of anodizers,
scattered over the whole country. But almost none of them were able to finish
the surface of my samples like we are accustomed to from our everyday goods like
HiFi, Laptops, objective lenses, smartphones etc. [..]
Long Story short:
I put a lot of work into my last design and willing to travel the world for a good result.
This is an international forum, so:

Any tips?
On Highend 2019 in Munich I visited a booth where a company had lots of front plates on display which looked very good to my unprofessional eyes. I think it was frontplatten-schmid (just checked the catalog). Maybe they can help you.

You may also contact Rainer Burzynski. He designs/produces equipment for camera tripods and is very critical with his suppliers. Maybe he knows a company which is good enough.
 
Joined
Nov 26, 2018
Messages
79
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56
#8
Hi LTig,
Frontplatten Schmidt is the reason why I started this thread, it was a disaster.
I did send the same aluminium samples to "Frontplatten Schmidt" and a second company "Eloxal Zwickau".
The samples from Zwickau were relatively good. They had the desired "Apple Look".
But "Frontplatten Schmid'"s samples were extremely dull.
Despite being sandblasted (This should even out scratches) circle marks from the plain milling cutter
were still visible. These marks are common and can be found on any sheet and plate designated for anodizing.
Some brushing with very fine Sandpaper removes them completely.
But the samples of both companies did show them.
Why?
Because you have to turn the plate in your hand and observe it from different angles of light to make
sure the marks are are gone.
Too much of an effort for all companies I triedso far.

I made some stabilizers for Sony´s Moving Pickup mechanism from the nineties and had the same Problem.
The only way to get good results was to polish the stabilzers almost mirror-like before
sending them in for sandblasting ! Almost got a tendinitis after one wekend of polishing 20 stabilizers
because some moron does not take 5 seconds to check his work...

Back to "Frontplatten Schmidt":
The samples were not only dull. Black looked grey, and one undyed alloy sample had black spots.

"Schmid" charged almost twice the price than "Zwickau" for this crap,
claiming they knew the bad result and payment has to be done nonetheless.
But the owner forgot that I phoned him after the parts were finished and before they were sent to me.
During the phone call he touted the good results. but obviously never checked them.
So "Frontplatten Schmidt" would make a good Team with TotalDac.

"Eloxal Zwickau" could have ended my search, but problems already began with the fact
that they do not read mails. Because after working on my (smaller) samples
they realized that the final parts would not fit into their machines -
but they had the information about the dimensions already for six weeks!
I gave the dimensions in my very first mail and also mentioned them on phone.

Fitting or not, the samples of "Eloxal Zwickau" loked good (Deep blacks) but
had minor anodizing flaws like, greyish "clouds" and mikro holes in one alloy.
The clouds result probably from the anodizing a bath lasteing too long,
the holes might come from chips of copper washed out by the acid.
These flaws are known to experienced anodizers and are controllable.
So I made Hi Res photos (did this with all companies before) and e-mailed them to "Zwickau",
but the owner did not want to discuss them.
He insisted I to send the parts back to him to examine.
Well - shouldn´t he have done this in the first place?

So same story, no one obviously checked the result and noted it.
Please define "sampling", honey! Flunked!
Zwickau declined anyway, stating that anodising prototypes was "too risky" to them.
Very german - we are world leaders in industry, so don't drag me out of my sofa!

But thanks for the tips, I will contact Rainer Burzsinsky.
BTW, Anodizing for motorcycles follows technical standards.
The standards are not as high as with devorative anodizing.
I.e. a scratch not being seen from half a meter distance is "allowed" and inside the norm ...
All the best and many thanks, Herbert
 
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