Supplies Needed:
The first thing to do is to get the following things together: First
on the list is the most expensive item: a 6 to 12 volt battery charger.
This item is what might make this too expensive for some paintballers.
I (and most other hot rodders) already have one, for my car. If you don-t,
then you will need to pick one up. 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.) =) The next item, though
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. To make the negative ground, you will need some aluminum
ground wire and aluminum-foil. 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.
No super-special chemicals or solutions necessary to make the colors; just plain-old fabric 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 in what 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 when adding acid and water.
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.
(Editor's Note: While Mr. Bowes recommends not using a glass container, we highly recommend use of glass within a plastic container to help keep the acid from eating through plastic, but keeping the glass less breakable in the event the container falls over.)
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. DonÀ Àt use hot water! YouÀ Àll
find out why in the next section.
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. The article
says nothing about this, and shows a picture with the lead right in there.
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 paintgunÀ Às parts. You can check out the
above, as well as pick the colors you like best. If you test out some colors,
youÀ Àll 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. (See,
told you to rinse it in cold water!) 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 anyways.) =) Should anyone happen to figure it out, I suggest you
submit it to Warpig so they can put it up for others who like it.
Also, this process is for aluminum. I don't know how, or if, it will work on other metals. (I doubt it.) 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. I figure this shouldn't be too big a problem with the guns, but just thought I should let you know about it.
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 in a gun however, 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 gun 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.
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Corinthian Media Services. WARPIG's webmasters can be reached through our feedback form. All articles and images are copyrighted and may not be redistributed without the written permission of their original creators and Corinthian Media Services. The WARPIG paintball page is a collection of information and pointers to sources from around the internet and other locations. As such, Corinthian Media Services makes no claims to the trustworthiness or reliability of said information. The information contained in, and referenced by WARPIG, should not be used as a substitute for safety information from trained professionals in the paintball industry. |