iPhone 5S screw length trap

[NiHaoMike]

http://blog.irepairnational.com/2014/09/30/iphone-5s-blue-screen-bootloop-restore-error-14-or-error-9/
Intentional trap to snag unauthorized techs or just an unfortunate design decision? I think it's the first one since the difference between correct reassembly and bricking is just 0.1mm.

[aargee]

So it looks like Apple purposely (looking at the lined pattern of the tracks) put some PCB tracks under the screw hole that would be compromised if a longer screw were to be used?

[dexters_lab]

Lol, thats apple for you!

I am not surprised

[_Sin]

Never attribute to malice that which can be adequately explained by stupidity...

(and it's a very dense board with little area left for routing and a lot of bits bolted together on top. Not surprised they had to put something under a screw point. Plus if you're careless putting something as intricate as a modern smartphone together, something will probably bite you.)

[DutchGert]

I don't think its on purpose just to 'screw' with the repair guys.

It's a very dense board so they probably could use all the space they could get. Including not drilling holes all the way through and use the space under the holes.

[sunnyhighway]

Using only 1.7mm and 1.2mm screws on the same assembly part would have made sense.
Adding 1.3mm screws to the mix is an accident waiting to happen.

The added risk of accidentally mixing of the 1.2mm and 1.3mm screws completely overrules the added strength of that 0.1mm in length.

[nctnico]

A couple of years ago I took an iPhone4 apart and I was amazed that every screw had a different length. That must be an assembler's nightmare.

[amyk]

Why exactly would they even want to have two, let alone three different lengths of screws to secure what looks like the same part ?Raises BOM cost and no doubt complicates assembly too...

If anyone here happens to have the boardview/schematic, check what those traces are for and that could give a clue as to whether it was intentional.

[tom66]

Hmm, when you're making millions and the screws are inserted by machine, I'm not sure BOM size is that critical.

We will often place a 1k and 1.03k resistor on BOM, instead of 1k and 30R, the cost for multiple reels in PnP is minimal when you make millions. Probably applies for screws too.

[German_EE]

Looking at the way traces were laid over the hole I say that this is a deliberate trap manufactured by Apple to catch out anyone attempting to repair the phone. Traces the width of a human hair inside a screw hole are not a way to design a quality product.

[ConKbot]

Wow, I know comcast isnt a hardware manufacturer, but I'm not sure even they are that low..

EDIT: just did a bit of poking with the ruler on a screen.  If thats a 1mm hole like they say it is, those are 2 mil trace/spaces. Located right at the bottom of a hole with an open ended solder nut right above it.   Given that they could have
A) ran the traces somewhere else
B) use a closed bottom solder nut
C)not brought the screw face within a few um of the face of the board (I mean really... does that 1.3 mm screw above it *really* need to be 1.3mm? is that extra 0.1mm make or break? just the the 1.2 for both... )

this wouldnt be an issue. 

[wraper]

I hate apple with their iphones. WTF they need something like 10 kinds of screws in a single phone, and many of them are very similar. It's really a pain to track every screw so it won't go in a wrong place when assembling back.

[HighVoltage]

knowing Apple, I would not be surprised that this was done on purpose.
The 1.2 mm screws would probably work perfectly alright in the holes for the 1.3 mm screws.

Unless they found out in the last minute, that in this particular hole, the 1.3 mm screw is too long and can cause damage.
.... but No, hard to believe !

[ataradov]

I don't believe that 0.1 mm increase in length can cause such a damage.

Using 1.7 instead of 1.2, now that I can see.

[george graves]

I don't blame apple for making their phones "hard to repair".  It's a design trade off.  I think they should weld them shut, and be done with it.

[TheBorg]

I don't blame apple for making their phones "hard to repair".  It's a design trade off.  I think they should weld them shut, and be done with it.

That's when our consumerist culture wins...

[c4757p]

I don't blame apple for making their phones "hard to repair".  It's a design trade off.  I think they should weld them shut, and be done with it.

waste, n. 1. Buying a phone that can't outlast its battery.

[Rigby]

That screw is probably 0.1mm shorter specifically so the traces can be routed under it.

When you have defined size and weight, you make a lot of otherwise odd decisions.

[george graves]

That's when our consumerist culture wins...

Not really.  I think you just have to accept that if you want something that compact, sturdy, and mass-manfactured it's not going to be repairable.  It's not like Apple is selling lawnmowers, or vacuum tube radios.

[brabus]

Actually, iPhone 4/4S/5 are among the easiest devices to repair, in my experience. I don't see any intention from Apple to prevent their devices being repaired.

In my opinion, if a bloke tries to repair the phone and is not mindful enough to put every screw where it was supposed to be, well... it's the bloke's fault, not Apple's.

p.s.: I am not an Apple fan.


Anyway, yes, putting two screws only 0.1mm different is pretty devilish. 

[george graves]

So your the iphone repair guy? 

[wraper]

Just for comparison. Galaxy S4 has 9 screws of one type and 1 screw of second type and different color!

[cimmo]

That's when our consumerist culture wins...

Not really.  I think you just have to accept that if you want something that compact, sturdy, and mass-manfactured it's not going to be repairable.  It's not like Apple is selling lawnmowers, or vacuum tube radios.

Tell that to all the people who have broken/cracked screens.
My sister dropped her iPhone 4S and was apparently told by Apple Au that they "do not fix broken screens. But you can buy a new iPhone 5".

A little bit of research discovered a thriving market for replacement screen assemblies (LCD and digitizer), I got one from an Au ebay seller for <$30. Several websites/videos explained the process and a few hours later the phone was as good as new.

Even the 4S has a dozen or so nearly identical but different screws - one website had good diagrams of the different screw locations, I used a strip of blutak to hold the screws as they were removed in the order as listed on a website and then returned them to their correct locations.

I also found tiny blocks of rubber and strips of foam glued in various places to hold things together - if these were applied by an automated process I'd be surprised - does anyone know if there is a machine that does this?

[owiecc]

Well if you just follow simple instructions from iFixit that state: "It is especially important to keep track of your screws in this step for reassembly. Accidentally using the 1.3 mm screw or one of the 1.7 mm screws in the bottom right hole will result in significant damage to the logic board causing the phone to no longer boot properly" you will not break the iPhone. I don't think that even unauthorized techs would be stupid enough not to check out iFixit for repair instructions.

[SirNick]

That screw is probably 0.1mm shorter specifically so the traces can be routed under it. ... When you have defined size and weight, you make a lot of otherwise odd decisions.

This was my initial thought, too.  It certainly could have been intentional, but that would require conspiracy between the board designer(s) and the case designer(s), and probably a few other folks too.  Much more likely, the odd screw length was chosen as an easy way to solve the problem of having too little clearance with their first choice in fasteners.  Could've even been a design error, and just no reason to rectify it with a new board or case when a different screw would button it up nicely.

But this is the most convincing argument:

I don't see any intention from Apple to prevent their devices being repaired.

There are a lot of tricks they could have played to make life difficult for aftermarket service techs.  So I'm skeptical they left the front door unlocked, but stuck a bucket of ice water on the door frame in case anyone tried to enter.