Changing anodized Aluminum to different color...

I have some blue laser hosts from Mohrenberg, found here:

Mohrenberg Blue Side Clicky Hosts

And I was wondering if anyone knows of anyway to change the color of the hosts? I was thinking this color Green.
I have a few criteria that I would like to stick to when considering how to go about this:

1) I do not want to spray paint the hosts, cause the paint will chip off. (or if
anyonc knows of a paint, even brush-on paint that won't chip, let me know.

and

2) I do not have the means to anodize aluminum, (or reanodize if that is possible).

I have heard of powder coating some type of metal, but I think that is a form of anodizing...

So, on those thoughts, does anyone know of a way to do this, or is it not possible?

Thanks in advance for everyones ideas!!! :yh:

Well to get a new anodized color you could ask around, would just have to strip the old anodizing. Powder coating is somewhat simpler, it's 'baked' on, Ehgemus does it, you could probably get him to do it for a fair price.

In order to change the colour you have to (as Prototype said above^)
strip the oxide layer containing the dye with an acid which reacts with
organic dyes, and not the aluminum. The most common method would
be caustic soda.

You have to be careful on the stripping for the following reasons,

-1 the fumes!! Take it outside. Cant stress this enough nasty fumes are created.
-2 protective goggles and gloves at minimum. Caustic soda will burn skin and
put holes in clothing.
-3 If the hosts are molded and not machined, the aluminum may not react well.
This is actually more important if re-anodizing after the strip. You get patches
where the oxide layer will not form, and the dye will not set. OR it sets lighter etc.


To anodize, you need at least:
- 10-20A @ 12v
- sulphuric acid bath
- aluminum plate (which sits in the acid hooked to the neg- terminal)
- aluminum wire to suspend the work in the acid bath
- well ventilated area as well
- and of course, goggles and gloves.

To get the new colour to set will take some practice. You can only strip
a host 2-3 times at most, then you will begin to erode the threads for the tail
cap etc. So any mistakes should be on scrap pieces.

Once you get the hang of it, its great. You can spend the money on a kit, but
can be done with hardware store items and for a lot less...

For the dye, get 'RITT' clothing dye or similar. Theres a variety of colours
available, just haven't found anything much other than earth tones.. No fancy
bright stuff.


And DONT try to strip or anodize any parts with different metals. Break
everything down and work with the aluminum only. Not much will survive
the stripping or anodizing process other than aluminum, lead, and stainless.
Have fun

:beer:


*edit*

Dont forget! when stripping, I soak the pices (after rinsing) in warm water
mixed with baking soda. If you dont neutrilize the acids completely, your work
will go from shiney the night before, and blotched and burned looking in the morning.

I would also suggest looking up some DIY guides on the topic. Pick up as many tricks
as possible.

Prototype said:

Well to get a new anodized color you could ask around, would just have to strip the old anodizing. Powder coating is somewhat simpler, it's 'baked' on, Ehgemus does it, you could probably get him to do it for a fair price.

Click to expand...

Powder coating could reduce the thermal performance though - unlike anodization, its a pretty thick layer of plastic material, which is a thermal insulator.

Oh, that totally slipped my mind, but I would think that a thin layer shouldn't adversely effect performance too badly.

Here is how you do it with Silver.... I would imagine its quite a similar setup for aluminum.

That was a Great reply Wannaburn!
I have always been curious about the process and thats a nice quick reply with some very good points. And i'm all about the safety when working with stuff like this....I almost blinded myself with industrial paint stripper....ANY project just isn't worth loosing your sight over!
+1 rep

bobhaha said:

Here is how you do it with Silver.... I would imagine its quite a similar setup for aluminum.

Click to expand...

Not even close... These are 2 completely different processes.

With aluminum you have to start with a pure surface, i.e the striping.
You then need to anodize, copper leads in the sulfuric acid will disappear,
and ruin the acid with junk.

An oxide layer forms on the surface of the aluminum in 20-45mins of bubbly time.
You then rinse your freshly anodized part in distilled.

You then 'dip' the part for a soak in the desired dye. Colour is dependent on time 1min ~ 15mins

When finished, the part is boiled in water for 20-30mins to seal the oxide layer
with the dye trapped in the pores.

These are completely unrelated processes, and if good results are desired
it takes much practice. Ive been doing my own for 4 months now, the first
5 attempts were mixed results. But it does not take long to get it right.

532 with Envy said:

That was a Great reply Wannaburn!
I have always been curious about the process and thats a nice quick reply with some very good points. And i'm all about the safety when working with stuff like this....I almost blinded myself with industrial paint stripper....ANY project just isn't worth loosing your sight over!
+1 rep

Click to expand...

Thanks... I have put a good amount of time into anodizing recently.
Its always good to be able to post some personal tips.

I of course save some goodies for myself :shhh:



This is the page I started reading first, still had it in bookmarks.

Though his method did not work 100% for me, its a good read.

DIY Anodizing guide - www.Motorcyclebuilders.net - You build it.. We show it to the world!

Powder Coating isn't much different that regular paint, except it's in a powder form and gets baked on. It's actually a rather thin coat of powder and when heated it flows together to cover part. As far as being a thermal insulator, it's hard to group all powder into one category because there is many types of powder for all different applications. Some powders are made to be thermal insulators, but your regular powders are equal to normal paint. It's easy to prep and to do and there is a ton of colors to choose from. I personally bead blast all of my aluminum parts to strip or prep before powder coating or refinishing. This is just my opinion from my experience with preparing my items for powder coating.

I suppose there are choices in thickness as well - i've seen very thin decorative powder coats, but also milimeters thick ones on automobile parts and such. As for the insulating effect: paint will do the same thing, but its generally applied in rather thin layers. Some paints can even help radiative cooling a bit, as they have very low albedo's in the mid- and far IR. Radiator paint would be a prime example, but its certainly not limited to that.

Hey Everyone, thanks for all of the great responses so far!!!

Everything has been very informative.

I am thinking I might try powder coating, (anodizing sounds a little bit too complicated for me at this time) but will I be able to powder coat over a anodized surface? I am thinking i can, but just asking to make sure.

Does anyone that has replied so far do powder coating and could explain the basics? I am going to do a quick google, but just wondering what people found that works and what doesn't.

And thanks wannaburn for being so detailed, your my type of person!!! +1 to detail.

I do powder coating and it's pretty simple to do. Your biggest expense will be starting up. You will need the powder coating kit, an oven, air compressor, and a way to either blast your parts or strip them. You won't be able to powder coat over anodizing, I bead blast it off, it's easier than chemicals. Let me know if you have any question and I'll do my best to help.

The automotive paint at wal-mart is great too. It's a spray though, but it doesn't chip. it has more a rubbery texture when dried

if you look in my photo album there a picture of a focus adapter i painted with it. I'm very impressed with it. it runs about $6 a can

viperx1101 said:

Hey Everyone, thanks for all of the great responses so far!!!

Everything has been very informative.

I am thinking I might try powder coating, (anodizing sounds a little bit too complicated for me at this time) but will I be able to powder coat over a anodized surface? I am thinking i can, but just asking to make sure.

Does anyone that has replied so far do powder coating and could explain the basics? I am going to do a quick google, but just wondering what people found that works and what doesn't.

And thanks wannaburn for being so detailed, your my type of person!!! +1 to detail.

Click to expand...

No problem, its a tricky process, the more detail the better...

Powder coat is an awesome finish on anything. The thick type have a nice plush look that
wreaks of quality. Im partial to anodize as I work mostly in aluminum, and like the final look,
even clear anodize looks nice and its easy.

Have a look at my link to the 'corrected labby' thread in my sig. That is the result
of a simple strip and 30mins in the anodize tank with no dye. It brings the shine
of the aluminum down, and gives a nice matt finish, hardened and scratch resistant.

I think you can powder coat over anodize as the surface of anodize is still conductive
and wont chip. The powder is applied via static charge, so the paint taking to the parts
shouldnt be a problem. The only thing I can think of that may cause some issue, is any
dark colour like blue or the common black anodize may affect the shade of the PC.
This would be less of an issue with a thicker application of PC.

There should be a shop locally that you can contact and ask if they charge extra to PC
anodized aluminum. If they dont explain the process, chances are a higher price would indicate
that they strip the oxide layer first.

You should be able to get that one answered with some googling or a call to a local shop...

Mohrenberg said:

The automotive paint at wal-mart is great too. It's a spray though, but it doesn't chip. it has more a rubbery texture when dried

if you look in my photo album there a picture of a focus adapter i painted with it. I'm very impressed with it. it runs about $6 a can

Click to expand...

I was mentioning to another member via PM, that a good paint I have tried
is epoxy based appliance paint. The colours as far as I know are limited
usually to white and black, but once cured make for a hell of a finish.

It has a nice shine and is tough as nails.

Stripping the anodized layer isnt required to get powder coat though - especially if the shop considers it a mainly aesthetic job. But even when it comes down to thermal performance, coatng over an anodized surface is not that bad. The anodized layer is typically very thin, and a decent thermal conductor too.

Keep in mind that any aluminium surface has an oxide layer. It may be no more than a few atoms thick, but in a natural atmosphere it will always be present. Its also the reason that aluminium is close to impossible to solder with normal agents.

I just read a snippit from wiki on the topic. Looks like anodized aluminum
has its advantages when painting over it.

From what I gather, because its more porous, the paint adheres better.
Though im guessing you would paint before sealing the aluminum.
Painting it fresh out of the anodize tank seems like an interesting idea,
but keeping in mind that a freshly unsealed anodized part is more delicate
until its boiled and sealed...

quote from wiki>

"Anodizing increases corrosion resistance and wear resistance, and provides better adhesion for paint primers and glues than bare metal. Anodic films can also be used for a number of cosmetic effects, either with thick porous coatings that can absorb dyes or with thin transparent coatings that add interference effects to reflected light. Anodizing is also used to prevent galling of threaded components and to make dielectric films for electrolytic capacitors. Anodic films are most commonly applied to protect aluminium alloys, although processes also exist for titanium, zinc, magnesium, niobium, and tantalum. This process is not a useful treatment for iron or carbon steel because these metals exfoliate when oxidized; i.e. the iron oxide (also known as rust) flakes off, constantly exposing the underlying metal to corrosion.

Anodization changes the microscopic texture of the surface and changes the crystal structure of the metal near the surface. Thick coatings are normally porous, so a sealing process is often needed to achieve corrosion resistance. Anodized aluminium surfaces, for example, are harder than aluminium but have low to moderate wear resistance that can be improved with increasing thickness or by applying suitable sealing substances. Anodic films are generally much stronger and more adherent than most types of paint and metal plating, but also more brittle. This makes them less likely to crack and peel from aging and wear, but more susceptible to cracking from thermal stress."

Link>

Anodizing - Wikipedia, the free encyclopedia