Build Quality Issues, Scuffgate

Section by Vivek Gowri

Despite all of the effort put into the iPhone 5, Apple has had its fair share of growing pains with the 5 design. The main thing here is definitely Scuffgate, which we'll get to in a moment, but it's not just that. My personal unit had an issue with the front glass not being properly mounted into the frame, something I tried to correct by just applying pressure until it clipped in, but it ended up unclipping again after some time. I'm not sure how widespread it is, but worth noting nonetheless. Add in the litany of other issues with the 5, including a fair number of nitpick-level complaints that SNL chose to poke fun at last weekend, and it's clear that this isn't a perfectly smooth launch.

Which brings us to Scuffgate, a two-fold issue that relates to the scratchability (scuffability?) of the new iPhone. Now, iPod users have been used to devices that are near-impossible to keep in decent condition for quite some time now. Any iPod with a chrome back (the first four iPod touches, all classic iPods, 1st and 3rd gen nano) is liable to scratch just by looking at it wrong, and there was actually a class-action lawsuit filed about this some time ago. But an iPhone that scratches easily is a pretty new phenomenon, which is why this is becoming a big deal.

These surface defects are commonly occurring on both black and white iPhone 5s, with the key difference being that the silver metal doesn't show imperfections nearly as much. The raw aluminum colour is a silver that's similar enough that unless you go hunting for it, in most cases you won't notice the texture difference. The black/slate 5s tend to show it pretty clearly though - the bright silver of the raw metal contrasts quite a bit with the dark finish, so even small imperfections tend to be high visibility. If you like to keep your phones naked (without a case or protective skin), I recommend going with the white 5. As sexy as the dark metal casing is, it starts looking a bit more low rent with a couple of scratches in it.

The other problem? People are having iPhone 5s delivered with noticeable scratches and dents, straight out of the box. Mine came with a couple of very minor ones that I only noticed after hunting for them, no big deal, but I've seen some aggrieved owners posting unboxing pictures showing relatively major surface flaws in the metal. In my opinion, this is the more concerning part of the "Scuffgate" equation. It's just not acceptable for significant surface defects to exist on brand new phones out of the box. With that said, I can understand how the 5 bodies are getting scratched in the factories. Let me explain, starting with the electrochemical anodization process for aluminum.

It works like this: the raw aluminum is submerged in an electrolyte through which a direct current is applied, growing an oxide at the anode electrode (the aluminum) and hydrogen at the cathode. Essentially, this is just a controlled electrochemical corrosion reaction. It results in the production of AL2O3, which we know as aluminum oxide (or α-alumina), along with a bunch of hydrons (H+) at the anode, plus dihydrogen gas (H2) at the cathode. The anode reaction looks something like this: 2 Al (s) + 3 H2O (l) = Al2O3 (s) + 6H+ + 6e-. As this process continues, a porous alumina film is created at the surface. This gives the slightly rough texture we're used to seeing on anodized aluminum products, but also allows for coloured dye to be poured in. The dye is then sealed into the material by putting the aluminum in boiling water. Professor Bill Hammack from the University of Illinois Urbana-Champaign biomolecular engineering department gives a pretty solid rundown of the basics in the video below, if you want a more visual explanation of the process.

Basically, the key to all this is the porous aluminum oxide layer. Based on the voltage, anodization time, and the specific electrolyte solution used, the depth of aluminum oxide created and size of the pores can vary. It's actually also possible to create a non-porous barrier-type alumina if an insoluble electrolyte is used in the anode, but that's a different story for a different time. Also, since this came up during the podcast and in the comments later, it's worth mentioning that aluminum reacts with air naturally to create a very thin oxide layer to protect the bare metal in a spontaneous mechanism known as passivation. By very thin, I'm talking on the ångström level - 50 of them, give or take. That's five nanometers, which is almost negligible, but more importantly, it's nonreactive to air beyond that so there is essentially no corrosion. This makes perfect sense if you think about how bare aluminum or any other raw metal reacts to air in purely physical terms, but it's always good to relate real-world observations to the chemical reactions taking place. Now, back to the various factors that dictate the properties of the anodization process - we don't have access to any of that information, beyond knowing that the specific aluminum being used is a 6000-series alloy. My digging suggests that it is likely some form of 6061, which is composed of 95.85%–98.56% aluminum, along with some combination of silicon, iron, copper, magnesium, manganese, chromium, zinc, and titanium, amongst other elements. It's hard to know exactly what Apple doing, but we're in a pretty good position to make educated guesses as to their methods and intentions.

A diagram showing the four steps of pore formation during the aluminum anodization process. The blue indicates the electrolyte solution, the light gray is the aluminum oxide, and the dark gray is the base aluminum. E indicates the flow of electrons. (Source: University of Halle-Wittenberg)

Apple has been anodizing handheld devices since the iPod mini debuted almost a decade ago, but obviously the process has been updated in the intervening years. The last notable change was a switch to an anodization process that resulted in denser pores around two years ago - it first showed up in the 2011 MacBook Pros and the iPad 2, eventually spreading to the rest of the lineup. The iPhone 5 takes that to a whole new level, with even finer and denser pores than I've seen used on any Apple product in the past (pore density is inversely proportional to pore size.) It's also a thinner metal than we've seen Apple use before. The material thickness for the iPhone 5 is just significantly thinner than they use on iPads or MacBooks, or even the old iPods that used anodized shells (iPod mini, 2nd, 4th, 6th generation nano, the last few iPod shuffles).

Which brings us to the next key detail with the anodization process: typically, the thickness of the anodization adds about half that thickness to the total aluminum thickness. So if you had an aluminum plate that was 1mm thick and added a 0.2 mm oxide, post-anodization, you would end up with a total material thickness of 1.1mm. With Apple trying to maintain as slim a profile as possible, it's in their best interests to have a relatively thin anodization. Given the graining of the anodization and based on what I've seen from scratching up my own iPhone 5, I think Apple's anodization process results in a super-thin alumina, something on the order of less than a hundred microns, at most; I'm estimating around 50-75um. (I'd also just like to note that in the process of this review, I took a jeweler's screwdriver to the back of my previously pristine iPhone 5. I love you guys, don't ever forget it.)

The oxide is even thinner on the bands, particularly the chamfers, which are just painted metal. So while the entire thing is easy to nick, it seems easiest to scratch off lots of paint on the bands, as well as the various metal edges. The soft-anodized surface is just a magnet. And the thing is, I'm not even sure they have the material thickness to oxidize more of the surface to get a more durable finish. The entire phone is so thin, and especially on the bands, I can't see a way for them to corrode any more of the aluminum than they already have without it raising questions about structural integrity. So, without very special care inside the factories, it's pretty easy to see how defects could occur. The rumors of Apple tightening down on quality control inside the iPhone 5 assembly factories comes as no surprise, since the 5 really does need extra attention to make it out of the factory unscathed.

So, are there any solutions to Scuffgate? Not really, or not anymore than there were with Antennagate. If you owned an AT&T 4, your only options were to put a case on it or just deal with the potential dropped calls. Here, your only options are to put a case on it, or just be very careful and deal with the potential scratches. If your phone came with defects out of the box, I'd just try returning it in hopes of getting a closer-to-perfect replacement unit. In the meantime, Apple needs to implement some controls internally to ensure that shipping devices don't contain any major surface-level defects. Maybe put some of those 29-megapixel cameras to good use. If Apple really wanted to fix it, they could put some sort of scratch-resistant polymer coating over the bare metal, but that'd absolutely ruin the surface feel. If I was Jony Ive, there's no way I'd let that happen, so until Apple changes up the design (like building antenna diversity into the CDMA 4 and 4S), we've just got to deal with it.

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  • darwinosx - Tuesday, October 16, 2012 - link

    The iPhone 5 display is better than any current Android display.
    But Motorola and Android if you want a company that is dying and being sold and a copycat cheap phone with no service and support.
  • V-Money - Tuesday, October 16, 2012 - link

    Your wisdom and informative argument adds tremendous value to this post. For the record though, the OP said specifically battery life and 720p display, so the response was relevant.

    The rest of your post is petty, get over yourself. If you are going to play the copycat card you should have done it before Apple decided to go with a bigger screen and use a (eerily similar) notification bar to what Android phones have had for years.

    As for quality (of display or otherwise), that is subjective analysis and considering that Apple only releases one phone at a time and Android manufacturers many, its a stupid argument for anyone to make. Case and point, I can find many android phones that are much more terrible than the iPhone, but I can also find many that are better. The iPhone is a decent phone, but its not for everyone. Every consumer has their preference.

    My point being there is not one-size-fits-all phone, so quit acting high and mighty with your close mindedness. You are not better than those around you because you bought into Apple's marketing, you are just a fool dealing with the first world problem of living such a meaningless existence that you have to hold on to the imaginary power an inanimate object pretends to give to you.
  • Alucard291 - Tuesday, October 16, 2012 - link

    I feel that your argument may be too good for him to reply to :)

    He seems awfully angry :D
  • crankerchick - Tuesday, October 16, 2012 - link

    Great reply. If there's one place I just want to exchange comments without playing the "my toy is better than yours" game, it's here on AnandTech.
  • Gradly - Wednesday, October 17, 2012 - link

    I'm sick of ppl comparing iPhone to other devices. I'm sick of those telling you iPhone borrowed the notifications slider form android and skipping the myriad of things that other borrowed form iPhone. Apple has always said that "we are not the first but we do it the best". I'm sick of those who still don't realize that before iPhone ppl were living in caves actually.

    I'm an Apple lover not an Apple fanboy. I just adore the design, aesthetics, and GUI of Apple devices.
  • Penti - Wednesday, October 17, 2012 - link

    It's sadly Apple that goes and patent UI-elements to use against their competitors that is why it's always brought up. It would be totally unnecessary otherwise. You might look at who's the inspiration otherwise and it's often not Apple. In reality we had capacitive touch screens (it's not Apples tech of course) before, app store before, Android even had an SDK out before Apple. Competitors like Symbian/Nokia, HP WebOS, and Blackberry are even allowed to use stuff like bounce back effect even without (or before) any agreement with Apple. They should have credit but they didn't all the sudden bring out their device with what we now call smartphone features, it lacked most functions at first and slowly iterated, it did a lot poorer in many areas then it's competitors was doing even before iPhone and the first few years it also showed in sales numbers which were not high at the first 2-3 years. It did show us how important a good platform was. Guys like Rubin had already figured that out though. So I'm not sure what they would borrow. Full WebKit-browsers on mobile is a good example of stuff they are co-developing but it was out in Nokia devices in 2006, netfront and Opera was never good alternatives to build into your platform. Stock Android don't have the bounce back effect, UI's looking like Apples and so on. Not even TouchWiz on Samsung's tablets looks like or infringes anything (design-wise) by Apple. They clearly have their own ideas. They are not the "me too", others might try to emulate them more in a business sense though. But they will be punished by the market by their execution instead of by Apple. It's not like any of the major players are fruit ninja-clones though.

    iPhone was desperately rudimentary at first. It didn't do applications and the web, messaging, photos etc better then anybody. What they did good was to iterate and improve. They take enterprise / corporate customers more seriously then Microsoft and so on in this field. Even if it took some time for them to get there. So they do plenty of good. It's a good platform, but it's not like they gave their competitors their blueprints for their devices / os of today back in 2007 and both have made many improvements. Well maybe not Microsoft but it takes a few years to start over. Apple has even got into hardware (components) a bit. Commoditization and convergence has reached far beyond the mobile field. That's great even if Apple won't enter them. Still don't know why any competitor would like to turn themselves into a retail giant and employ mostly store staff as Apple does – Microsoft should start doing what they are good at instead. Google would be the most evil company in the world if they had started to patent and sue based on UI-features and methods. Or if they really tried to stop Bing and Bing Maps (and getting it banned in some markets) for example. It doesn't really matter who was first and who invented what if you take it to court were that doesn't really count and that creates a lot of BS surrounding the whole issue and companies involved that is largely unnecessary. But the real silly thing is why they fight. It's not based on IPR, it's basically that they want to be alone in doing whatever, even if they can't really make that claim to have sole rights to something. But ultimately courts do get that under control even when corporate leaders turn to fighting outside of releasing product.
  • slickr - Tuesday, October 16, 2012 - link

    LOL. Don't make me laugh. It has still the worst display and has had the worst display for at least 3 years.
  • A5 - Tuesday, October 16, 2012 - link

    Your response is just as dumb as his. The iPhones have excellent displays.
  • medi01 - Wednesday, October 17, 2012 - link

    None of the iPhones have anything to compare with AMOLEDs, on top of having idiotic resolution.

    On tablet space, only iPad 3 matched color gamut of THE FIRST Samsung Galaxy Tab.
  • thunng8 - Wednesday, October 17, 2012 - link

    How does 67.5% of sRGB on the galaxy tab 10.1 match the 94.4% on the ipad 3?

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