Making aluminum look rusted (not oxidized)

[dryvr12]

Ok, I posted this somewhere else but I can't remember where. I have heard to rust aluminum, just wrap the piece in steel wool and stick that in water. The steel will rust and stick to the aluminum. I haven't tried this out, so if anyone does, please post pics.

Edited April 8, 2010 by dryvr12

[Harry P.]

Uh, just so you know... aluminum doesn't rust.

[Guest Gramps-xrds]

Uh, just so you know... aluminum doesn't rust.

Harry that's not exactly right. When aluminum rusts it turns white and powdery.

[sjordan2]

Ok, I posted this somewhere else but I can't remember where. I have heard to rust aluminum, just wrap the piece in steel wool and stick that in water. The steel will rust and stick to the aluminum. I haven't tried this out, so if anyone does, please post pics.

The question is, are you intending to use workable aluminum material to represent steel?

[dryvr12]

The question is, are you intending to use workable aluminum material to represent steel?

Yes. I think ill change the title..

[dryvr12]

I think the correct term would be Oxidized...

This is from the Site WiseGeek.com:

A freshly-cut apple turns brown, a bicycle fender becomes rusty and a copperpenny suddenly turns green. What do all of these events have in common? They are all examples of a process called oxidation.

Oxidation is defined as the interaction between oxygen molecules and all the different substances they may contact, from metal to living tissue. Technically, however, with the discovery of electrons, oxidation came to be more precisely defined as the loss of at least one electron when two or more substances interact. Those substances may or may not include oxygen. (Incidentally, the opposite of oxidation is reduction — the addition of at least one electron when substances come into contact with each other.) Sometimes oxidation is not such a bad thing, as in the formation of super-durable anodized aluminum. Other times, oxidation can be destructive, such as the rusting of an automobile or the spoiling of fresh fruit.

We often used the words oxidation and rust interchangeably, but not all materials which interact with oxygen molecules actually disintegrate into rust. In the case of iron, the oxygen creates a slow burning process, which results in the brittle brown substance we call rust. When oxidation occurs in copper, on the other hand, the result is a greenish coating called copper oxide. The metal itself is not weakened by oxidation, but the surface develops a patina after years of exposure to air and water.

When it involves oxygen, the process of oxidation depends on the amount of oxygen present in the air and the nature of the material it touches. True oxidation happens on a molecular level — we only see the large-scale effects as the oxygen causes free radicals on the surface to break away. In the case of fresh fruit, the skin usually provides a barrier against oxidation. This is why most fruits and vegetables arrive in good condition at the grocery store. Once the skin has been broken, however, the individual cells come in direct contact with air and the oxygen molecules start burning them. The result is a form of rust we see as brownish spots or blemishes.

Oxidation can also be a problem for car owners, since the outermost layers of paint are constantly exposed to air and water. If the car's outer finish is not protected by a wax coating or polyurethane, the oxygen molecules in the air will eventually start interacting with the paint. As the oxygen burns up the free radicals contained in the paint, the finish becomes duller and duller. Restoration efforts may include removing several layers of affected paint and reapplying a new layer of protectant. This is why professional car detailers recommend at least one layer of wax or other protectant be used every time the car is washed.

The secret of preventing oxidation caused by oxygen is to provide a layer of protection between the exposed material and the air. This could mean a wax or polyurethane coating on a car, a layer of paint on metal objects or a quick spray of an anti-oxidant, like lemon juice, on exposed fruit. Destructive oxidation cannot occur if the oxygen cannot penetrate a surface to reach the free radicals it craves.

This is why stainless steel doesn't rust and ordinary steel does. The stainless steel has a thin coating of another metal which does not contain free radicals. Regular steel may be painted for protection against oxidation, but oxygen can still exploit any opening, no matter how small. This is why you may find a painted metal bicycle still damaged by rust.

While this doesn't answer how to do what you want, it should clarify the use of the term "rust".

(& don't "tl;dr" this! (that's Too Long; Didn't Read for the non-acronym, TXTing crowd))

Yes I know all about this. My science project a few years ago included trying to rust different metals and it's outcomes. I just had a typo in the title.

[Harry P.]

Harry that's not exactly right. When aluminum rusts it turns white and powdery.

He was asking about putting aluminum and steel wool under water to make the steel wool rust, and would the rust then stick to the aluminum?

That's not accurate, because the rust that forms on steel wool is iron oxide, which is reddish brown. Aluminum would never have reddish brown "rust" on it, which is why I told him that aluminum doesn't "rust" that way.

[Guest Gramps-xrds]

Now that we've established that rust on any metal is oxidation no mater what color it is. To answer the original question, will aluminum take on the redish color of iron rust. From my experiences being around both, yes I have seen aluminum get stained from iron or steel rusting on it. Especially if the aluminum has already oxidized. Now how long it's gonna take you get it to stain is something you'll just have to find out for yourself. I would say that when you get any coloration on it you'll have to let it dry and do it again and again until you get the desired affect. I hope this answers your question. On another note, to me it would be easier and quicker to use paints and pastels to get the effect you're looking for.

[diymirage]

Uh, just so you know... aluminum doesn't rust.

you know, i used to work as an overhaul mechanic building VW engines and a lot or them had aluminum oilpans and let me tell you, the really do, shall we say, corrode

it does not turn what in car terms is called "ford brown" but more of a white as mentioned but it most certainly rusts

now, as for how to achive this in a model, i have no idea

[Smart-Resins]

if indeed what you are doing is using aluminum and you want it to look like rusted steal, try using Dr. bens instant rust! Absolutly terrific stuff. professional results the first time! Too easy to use! Must try it!It can be found on train sites or on ebay, where I bought mine! Seller was great!Jody

[MikeMc]

I remember the alcoa factory mags I had on my 70's Mustang...they did rust, my father a metalurgist said that was due to ferrous contamination at the foundry...

Edited April 9, 2010 by MikeMc

[DPink]

You do know that rust is another name for oxidization, right?

[Jantrix]

Are you guys seriously arguing about this?

To the thread originator - why would you want aluminum to look rusty and what does that have to do with modeling?

[Casey]

To the thread originator - why would you want aluminum to look rusty and what does that have to do with modeling?

dryvr12

Member Since 26 Jun 2008

OFFLINE Last Active Aug 24 2011 03:58 PM

Mr. Pink dredged up an old topic which had been very well answered, and I'm not sure why, since this question has been answered.

[southpier]

i'm taking Mr Pink off my buddy list!