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Any good Anodizers - Worldwide?

Herbert

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Nov 26, 2018
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#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
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#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
 

NTK

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#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.
 

Herbert

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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

Addicted to Fun and Learning
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Location
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#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.
 

DDF

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#7
Custom anodized aluminum features in allot of custom motorcycle builds. It might be worth exploring their supply chains
 

Herbert

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#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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Herbert

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#9
The journey continues, Stalder in Switzerland does not do bead blasting. They -like many anodizers-
advise that the mechanical and chemical treatment are done in house to prevent problems during the process.
As I wrote, Frontplatten Schmidt is a ripoff, I paid the double price for their poorly manufactured crap.

In the photo attached you can see the same alloy after anodising.
Left is Schmidt, right is Zwickau. The black stains are not dirt,they are errors from anodising.


Schmidt-Bad01.jpeg


As you can see, Zwickau did it well for half the price but my casings are too large for them.

Next samples, anodizsed naturally and anodized black.
Again, the left sample is Frontplatten Schmidt, the right sample is Zwickau.

The light samples are the same alloy, the black samples were even cut from the same plate.
Notice that Schmidt spoiled the blacks and rounded the edges during brushing. And in the dull plate on the far left, they did even not care to remove the circular markings from the milling. So this is the kind of company you can meet at a Highend Fair...

Schmidt Bad02.jpeg


So any proposal for better anodizers is still welcome.
 

Herbert

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#11
Thanks a lot but Alucol dors not do prototypes, does not brush or sandblast inhouse, does not do bright dipping (i.e. glossy surfaces). Just like the majority of providers, they anodize in large quantities without much handwork and quality control- atleast 10% are calculated to be thrown away. As mine are unique parts, I really need a company where one person takes the time needed for quality control and rework if needed. My experiences until now was that my samples were just packed and shipped with obvious errors...
Last time, a company as big as Alcol (Rohde in Germany) even declined to discuss obvious
errors as it was not clear whether it was them or if I bought bad material, Obviously
time is money so at one point they shut the door.

So I guess the solution for my problem should be a one man band or a very small company where you can directly communicate with the workers…

So I will still look but I am also contemplating of doing the brushing and anodizing myself
at one day.
But there are time and space constraints right now. You need a ventilated workplace
and the bath themperatures need to be controlled as well. Acids need to be disposed. Much more than to just find a dustless placei.e. for spray painting...
But one future plan of mine is to repair/refurbish anodized front plates of vintage audio gear. But again in contrast to simply painting a part, brushing and anodizing is more time consuming and silk printing comes into play as well...
 
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Herbert

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#13
Shorty, thanks a lot, but I guess you are following a misconception:
Your smartphone, your laptop, your car interior, your Hifi-gear: They all have shiny surfaces.
But this does not happen by default when anodizing. In fact the aluminium-oxide layer
is dull. This is why bright dipping (the same as elektrolytisch polijsten in dutch) is needed before
anodizing to make the layer less dull and give a silk shine.
But this needs acids that are not easy to handle, like nitric acid.
And the majority of aluminium anodized is not for decorative surfaces.
Dull or shiny, the protective function of the layer is the same.
and architecture or mechanical components are the major industries.
This is why just googling does not help at all and ATM or Alucol offer what 90% of all anodizers offer:
Dull anodizing with sulfuric acid and mass production.
The companies I am looking for must explicetly offer sandblasting / brushing / polishing/ bright dipping as well as prototyping!
 
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#14
Well, Alucol‘s website mentions they do polishing, as well as brushing. So you are looking especially for bright dipping? And all the outfits you contacted cannot even refer you to some company that’s capable to do what you want?
What is the process? Chroming followed by a layer of colour?
 

Herbert

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#15
Again, mechanical polishing is not the same as chemical polishing. I.e. If you want to do mirrors made of
aluminium, chemical polishing plus a very thin anodizin layer (5µm to 7µm) are a must.
Architectural Anodizing needs 25to 45 µm.
Second, yes, some outfits mentioned others.
And on the paper/phone/websits they seemed to be capable. As I wrote, I did send samples to about 8 companies, all came back with errors:
Unremovable grey stains, bad (hand) brushing, (uneven lines), irregular bead blasting (contaminated blasting material),
dull layer (etching during degreasing too long ), surface not properly sealed (absorbs grease or chalks)

I cannot stress this enough. It never took me more than 5 to seconds to find the flaws under normal lightning conditions
Mostly they were visible at first glance when unpacking. Check the second photo in post #9:
The plate on the left shows diagonal lines. These are marks from milling. No one cared to sand them out
before bead blasting. Visible at first glance. This company even works for HiFi-manufacturers
How many hours does one need to find even a tiny scrach or dent on his brand new smartphone or Yamaha-amplifier?
Anodizing has become highly mechanized:
When you brush 5000 tiles for a facade, this can be done automatically in a configurated assembly line.
If you anodize 5000 samples, the whole chemicals and steps anodizing process can be ajusted to the needs of the alloy.
I.e. EN AW 6060 becomes less dull during etching than EN AW 5754.
But with just one piece or maybe three, things are left to human error and carelessness.
When you are good in German (but google translate is almost flawless from German to Dutch
and vive versa) check www.electronic-thingks.de.
The "wizardry" of anodizing is well explained...

Bottom line:
The problem is not that prototypes / single pieces cannot be done well.
The problem is that the infrastructure of all outfits I encounteredis laid out to mass production with automated processes.
No room for the single worker and his "handbath", the term for the manually done anodisation
who is allowed to take hours if needed for the process.

Being a grinder / polisher once was certificted a training occupation, in the beginning of the second half of
the last century, this is not needed any more...
I already started to check the small towns in eastern germany that have a tradition in handmade watches
as I expect to at least find capable grinders there...
So my demands are: Brushing and Satinizing with homogenous structure using parallel hailrline,
Carefull pickling while degreasing and bright dipping during anodizing. Titanium colors not must, as some alloys
do tan themselves. (The Accuphase "Champagne" origibates brom there Titatium grey wuild be nice but is not a must...
And of course no scratch allowed during handling / packing...
 
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