Guide Annodizing for dummies 101

Anodize your pc at home
Boyd Roller
January 2004
*Warning* The chemicals used in this process are dangerous and can injure or kill you if you are an idiot or are not being careful!
Bit-Tech IS NOT RESPONSIBLE TO YOU OR YOUR EQUIPMENT IF YOU MESS IT UP!
Often anodizing is considered and/or presented as a difficult and expensive procedure. As it turns out, it really isn't that hard or that pricey.
Supplies Needed: : First on the list is the most expensive item: a 6 to 12 volt battery charger. They run from $45.00 to $110.00 depending on model, functions, etc. While it may seem like a lot, it does have other uses. (You could charge a battery, for example.) =)
Next, although not that expensive, will take some effort to find; battery electrolyte, a.k.a. sulfuric acid. This should be available at a battery wholesaler for about $2.00/gal.
You will also need aluminum wire and aluminum foil to make the negative ground. The wire can be found at an electronics store for about $35/spool, and you should have the foil in the kitchen. If you happen to be out of foil, you can pick up some more at the store when you go to buy the last item for this project.

To actualy color the item, you will use some ordinary clothing dye. (Something like Rit dye, for about $5.00.) Rit offers something like 30-40 different colors, so you have quite a number of choices for what color you want your parts to be.
An optional item is nitric acid: about $25.00/2.5 L. (This is used to clean parts prior to anodizing, but there are some cheaper alternatives. See end notes.) This is available at chemical supply stores. Should you not be able to find any, you can try to get on the good side of the high school science teacher. He may help you out since you only need a few ounces.

Safety Precautions: There are a few precautions I want to go over to help keep you from blowing up the house or trashing the garage. First of all, do not mix or store your anodizing solution in a glass container. Something could happen to make it break, and most households are not equipped to deal with that kind of spill. You also don't want to knock over the container, so a stable, rubber bucket makes a good choice. You will also need to be certain that the part you want to color will fit in the container without sticking out of the solution, and without touching the negative ground in the bottom of the container. Any acid that you don't use, keep it in what ever container it came in, or an old plastic bottle, like a bleach bottle. You can also store your used solution this way for doing more parts later. (Make sure that there is absolutely no bleach left in the bottle. Acid and bleach make chlorine gas. Very bad. Don't breath. Poisonous.)
Safety also applies to the nitric acid, but in a different way. It is imperative that you label and keep track of this stuff, as it is a stronger acid than sulfuric, and more dangerous. The breakage/spill problem is not as likely since you won't have that much around. (Unless you bought more than a few ounces from the chem store.)

The last note about the acids, is to mix properly. Always pour acid into water, never the other way, and do so slowly, being sure to mix in well. There is a reaction taking place and it releases a lot of energy. During the anodizing process, you will be running electricity through a weak acid solution. This creates hydrogen (just like charging a battery) which is very flammable. This stuff burns at the speed of thought when ignited, so do be careful. (Read as Remember the Hindenburg?) Make certain that there is some way to ventilate the project area, and DO NOT let any sources of ignition near the project area. Other precautions you should take include: safety glasses, rubber gloves, and maybe some sort of drop sheet under the area.

Preparations : One of the most essential things you need to do in order to get even color over the whole part is to be sure that the part is absolutely clean. You want it free of all contaminates, from dirt to the oils in your skin. This is where the nitric acid and some rubber gloves will help. A solution of 1-2 ounces of nitric acid in a gallon of distilled water will allow you to clean the surface in preparation for the anodizing. Aluminum oxidizes very quickly when exposed to air, so the easiest way to keep it clean is to clean it just before you are ready to start working on the piece. (You should rinse the part with distilled water before you put it in the next acid solution.) Other options are carburetor or brakes cleaners, or other similar degreasers. Soap and water will work also, or cleaners like Simple Green. These are cheaper, a nitric acid wash is the best. (You decide, it's your money.)
Make your negative ground with the aluminum wire and foil. Shape the end of the wire into a paddle shape and cover the round part with the foil. What you want to do is create a flat, round shape to sit on the bottom of the bucket, with a lead that comes up out of the bucket. You will clip the battery charger's negative lead to the wire that comes out of the bucket.

When you are ready to start, you will want to mix up your immersion solution. In your rubber bucket, combine the sulfuric acid and water to come up with a solution that is about 30% water. (1 part water to 2 parts acid.)

Place the paddle in the bucket and attach the negative lead. Then attach the positive lead to the part, making it an anode, and immerse it in the solution. (Remember that the two leads the paddle (cathode), and the part (anode) should not touch.) This is the best time to turn on the charger: once the part begins to fizz, leave it in there for about 10-15 minutes. After about this time the part should no longer conduct electricity. (You can also use an ohmmeter to check conductivity, but this is not needed.) Turn off and disconnect everything, and rinse the part in cold water. Don't use hot water! Hot water seals the surface and will not allow the coloring to set in.
A couple of notes: I have read some other procedures that say it is important that the copper lead from the charger does not enter the acid solution. It may take some trial and error to find out if this is a problem. It wouldn't be a bad idea to get some scrap aluminum and play with it before you start anodizing your pc's parts.
You can check out the above, as well as pick the colors you like best. If you test out some colors, you'll also learn just how long or short you need to work with the color solution.

Color: So now it doesn't conduct electricity, and is ready for color. It's been rinsed and waits eagerly to change to a new look. Don't wait too long to do the color, due to that oxidizing thing again. You want to mix up a strong solution of dye and water, in a container that can be heated. The solution needs to be at low heat, such as on the stove, so bread and cake pans work well. Again, you need something that will fit the whole part, but it's okay if it touches the bottom this time.

I would recommend turning parts every few minutes just to make sure that you get all-over color. Inform your mom or wife that the pan can (and will be) washed out. It is important that the heat be low enough. If the solution gets too hot, you will seal the surface, and it will no longer take any color. Leave it in the dye until the part is slightly darker than you want it.

The next step is to seal the surface of the metal in clean, boiling water. This will leech a bit of color from it, thus the slightly darker color in the previous step.

End Notes: It is important to realize that the process described above will yield only one color on your part. At this time, I haven't found out how to do any of the splash type of anodizing. (That's okay though, it looks really ugly anyway.) =) Should anyone happen to figure it out, I suggest you submit it to the end of this thread and I will edit it accordingly for others who like it.
Also, this process is for aluminum. Anodizing only works well on rock metal like bar or sheet stock, as opposed to castings. If it was forged or machined, it should have the density to take color through this process.
Something to consider when looking for a charger, is how many amperes it puts out. Without getting into any mumbo-jumbo, anodizing relies on 10 to 40 amperes per square foot. For small brackets and such, this is no problem. The larger parts may need the higher levels of amperes. The other note about part size, has to do with how long you leave it in the solution. Above it said 10-15 minutes, but that is for a smaller part. The larger parts may not only need higher amperes, but more time as well. I would recommend an ohmmeter, but again, I have one already.

So there you have it. Quick, fairly easy, and not too expensive. If you don't have the charger, then your first anodizing session could cost as much as sending your parts out to be done. But, then you can do it again for much less. Or do your buddies stuff. Or talk them into chipping in on a setup for all of you to use. We all know ways to help make things cheaper.
And the stupid statement required to cover myself... If you try this and something gets messed up, or someone gets hurt, you are on your own. Deal with it, you can't blame it on anyone else.
Mod on all!!!!

 

Wow... Nice tut man! I know I'd never do it, but you did an elaborate job of covering all the bases. Two thumbs up!

(P.S. If you could get some pictures of this process, that'd be really cool.)

 

really great tutorial dude
extremly usefull

what type of paint an be used? only the one for clothes?

 

Great guide, very detailed.

Could this be used to anodize a heater core to be used as a radiator in a PC?

 

ZapWizard, I am no expert on this topic, but cant see why you could not anodize a heater core.

Its made from metal. Although I do not think you'd want to fully submerge the core into the bath.

 

Anodizing only works on aluminum and Titanium. It really is not as simple as it sounds. I bought a semi pro anodizing line and still could not get good results even when following the directions to the letter. If you want a total custom job your best bet is sending it to a pro anodizing shop. There are a few here in the states. Anotech and PK Seletives are the best at custom stuff. They can even do designs and fade all kinds of cool stuff. I would sugesst that you try them out. And just to let you know RIT dye does work for anodizing but fades very quickly in any type of light.

 

Great guide!

Zapwizard: There is a gay biker (I'm serious) that comes my chrome shop for anodizing like that. He has a cute little transmission cooler radiator that he had annodized in pink. I'm not sure as to the thermal properties post-annodizing, but it certainly looked good. It was an aluminum radiator.

 

vonkaar - Where in Dallas and which chrome shop? I'm interested in a place around here.

 

Do you have any pics of any home anodized stuff? Interested in the finish.

 

Show N Go. Forest and Plano Rd, Garland. Considered by many to be one of the top chrome shops in the state. I know several low-rider clubs that will *only* deal with this shop. So far, I'm the only guy that brings PC stuff in to get chromed, and they love making fun of me for it .

 

Speaking from experience:

If you ever want to clean an anodized part for any reason, DO NOT use engine degreaser, carb cleaner, or any harsh solvents. It will take the anodizing off of even professionally anodized parts.

 

Anything that is very alkaline will take anodizing off. If you want to strip a part the best thing is powdered drain cleaner or lye. mix a strong solution in water tie a bit of string to the part and let it hang for a minute or 2 in the bath and you have raw aluminum. If the anolidic layer thick you might have to rince and repeat a couple times. After you are done rinse the part very very well. Then polish or what ever you are going to do to the part.

 

What would the Al look like if you are to do the electrolysis and then boil it right away, like normal aluminum, except it won't oxidise?

 

There would be a slight yellowish tint to it... after boiling...
as for the dying, the suggestion for the type of clothing dye is only what I have used, there are other dyes that will work too, mostly it is just from experementing with sample pieces to get the look and colors you want, also you can try testing the piece in sunlight to see what effects will take place... you might even be able to find some sort of uv reactive dyes that will work too.....

 

im going to have to try this...
wheres the pics!!!

 

can this been done with any other power sources

like i read it says 6 to 12 volt

so what about a computer power supply

and not sure how much volts a car battery gives but could that work

why the battery charger?

and is there anywahere that has pictures of this process since im a visual learner

 

Car batteries are 12v

I too want to see some pics...

 

The reason you use a car battery charger is because of the amperage they produce, If you use something with lower amperage, it may burn out the power supply or take forever to annodise. I will be posting a picture as soon as I get ahold of some more sulfuric acid... which isn't easy here in Korea...
The reason I said 6-12 volt charger is because that a lot of chargers will charge motorcycle and car batteries, and a lot of the cycle batteries are 6 volts. There are some pics of annodized and dyed items on my friends bar's web site... www.geocities.com/chickenheadlab just look at the lab section and you will see a red and blue dyed housing... the blue one was only a light dye job.
It will give you an idea of some of the outcomes....

 

So when the part is anodised (NB correct spelling ) does it not conduct electricity at all? Only I had a cool idea for a project a while back but it relies on being able to pass enough current through anodised Alu to light a LED

 

Nice tutorial!

I miss two things though:

- The technical explenation of things, like, why do you have to put it in a bath with a charger, what happens to the aluminium then? what's the differince compared to regular dying?

- And pics!