tiny rust spot on Unibody MBP

[GGJstudios]

Two different processes that use more or less the same physical principle to adhere a coating to a metal surface.

The two process do NOT use the same physical principle. Rather than continuing to post misinformation, you should learn what you're talking about. Since you don't appear to want to take the time to look it up, I'll do it for you:

Powder coating is a type of coating that is applied as a free-flowing, dry powder. The main difference between a conventional liquid paint and a powder coating is that the powder coating does not require a solvent to keep the binder and filler parts in a liquid suspension form. The coating is typically applied electrostatically and is then cured under heat to allow it to flow and form a "skin."

Anodizing, or anodising, is an electrolytic passivation process used to increase the thickness of the natural oxide layer on the surface of metal parts. Anodization changes the microscopic texture of the surface and can change the crystal structure of the metal near the surface. Anodic films are generally much stronger and more adherent than most types of paint and metal plating, making them less likely to crack and peel. The anodized aluminium layer is grown by passing a direct current through an electrolytic solution, with the aluminium object serving as the anode (the positive electrode). The current releases hydrogen at the cathode (the negative electrode) and oxygen at the surface of the aluminium anode, creating a build-up of aluminium oxide.

Powder coating involves adding a powder, applying it electrostatically, then curing it under heat, forming a skin on top of the aluminum. Anodizing doesn't introduce an external material, but rather simply increases the thickness of the natural oxide layer that already exists on the surface. The two processes and results are as different as night and day. Regardless of your personal, uninformed opinion, Apple DOES use anodized aluminum. The fact that you disagree doesn't change the facts.

I'm not a "fanboy" or any other kind of "boy". I don't think any company is infallible, and I don't take anyone's word as "gospel". I don't "love" Apple. I use an Apple computer. It's a computer. Duh! It's not something to get emotional about. It's a tool. It's not a perfect tool, but it's better than the many Windows PCs I've used since PCs were invented. I'm sure something better will come along in the future. The fact that I use a Mac doesn't mean I agree with everything the manufacturer says or does.

Anyone who thinks that Apple can misrepresent the materials it uses without violating truth in advertising laws, spawning thousands of lawsuits and negative publicity, is mistaken. If you exercise just a little common sense, you'd realize that Microsoft and other competitors would make a big deal out of any false advertising statements by Apple. Remember all the negative press about the NVIDIA problem? And that was NVIDIA's fault, not Apple's! Are you really naive enough to think that, with all the publicity the shiny aluminum Macs get, that critics wouldn't make a big deal out of it not being anodized, as Apple claims?

If it's a matter of your word against Apple's, I think Apple has a slight advantage in the area of credibility.

 

[drewsof07]

But that anodized layer can be chipped off. I have done so using only a poorly placed magsafe adapter (oops) and uncovered the aluminum beneath. It looked something like this on a much smaller scale.

Also, an anodized surface must be sealed using chemicals. Perhaps they can interact with the oxide coating under certain circumstances.

Edit: body oils can turn yellow/brown when left out and collect dust/dirt.

 

[allanibanez]

i just found a brown blob on my mbp. my advice - lick your finger, rub the affected area and presto, blob gone!