Using The Wrong Screw: A Painful Lesson In IPhone Repair

iPhone trace repair

If you’ve ever had to repair an iPhone for a friend, you’ll know they have a ridiculous number of screws. Most companies standardize screws in their products, but since Apple doesn’t expect you to fix a phone yourself… they may have let this one slide.

You see, each of these screws is different.iPhone screws The red ones are 1.7mm long, the yellow one, 1.3mm, and the orange one, 1.2mm.

Guess what happens if you install either red or yellow screws into the orange spot, since your eyesight isn’t good enough to notice a 0.1mm difference? The screw will cut into the PCB and break several 50 micron traces, as shown in the picture above, causing a blue screen error on the phone.

Fun stuff.

[Sam Schmidt] is the owner of a repair outfit called iRepairNational, and he and his team spent a day trying to figure out the problem – it’s not exactly easy to spot. They’ve managed to repair it by cutting thin strips  of copper foil (the width of a human hair) and floating it into place using the surface tension of the flux they were using for soldering. On average it takes them around 2 hours to do the repair, though they’ve done a few in just under an hour.

Since discovering and sharing the problem, they’ve had customers around the world sending in phones for repair – often at the fault of someone else trying to repair something completely different in the phone, and then using the wrong screw as they put it all back together.

126 thoughts on “Using The Wrong Screw: A Painful Lesson In IPhone Repair

  1. cannot se a 0,1 mm difference, you blind idiot!

    Props on making it work again, almost every person and company would have binned the Phone. Even when shared this solution is usefull for almost nobody.

    1. eh hellloooowww!!!!!!! some us are in our 40’s and 50’s and are starting to develop far sightedness “egg ovaling of the eyeball causing focus problems”

      also some of us have had small objects hit and scratch or even cut a couple layers of the cornea affecting the focus.

    2. In addition to a regular screw map, does anyone have a diagram showing iPhone 4s screw SIZES as well? I WAS using a screw map (albeit not magnetic) and the cat jumped up onto it….GRRRRRR. I don’t want to make that fatal “0.01 mm” error and wreck the phone! I’ve used a digital caliper to measure all of the screws (about 5 times each!!) but need to know which screws go where. Any help appreciated! Thanks! Patti

    3. You can’t screw up the yellow screw, it’s significantly demagnetized due to it being near the compass IC.

      And the red screw top left, is noticeably longer than the other two lower ones.

      Easy solution? Don’t screw it in the whole way if you are not sure if it’s the correct screw. And of course don’t force it in. Also don’t screw it all the way in if you feel too much resistance.

      1. on my phone there couple of stripes and sometimes touch screen do something itself after assembling phone and probably i install the wrong screws. Do you think screws make that cause?

  2. Very kind of you Sir, to post this valuable and useful into. Will save many hackers that fix their own a great deal of grief if they are not color blind.

    Excuse me Sir. How is this a hack?

      1. Actually Sir, you are incorrect. I’ve been hacking since before 1975 and professionally employed at the bleeding edge of the field most my years, plus my hobby is hacking. You may even have attended one of my classes.

  3. This is new. Boobytrapping the circuit board against 3rd party repairs.

    One would think it would have been cheaper for Apple to use one standard size screw and design around them to simplify assembly.

    1. It’s Apple, since when do they have to do anything to cut costs? They can put whatever price tag they want on their products and people will still pay it. Their marketing machine is insanely impressive.

      1. The point is that they could have used the short screw for every hole.

        It simplifies materials sourcing, assembly and quality control, which in the end could save them millions, and it’s just safer to design because you don’t accidentally specify the wrong screw in the wrong place.

        They just went out of their way to boobytrap the board, so third party repair shops would brick their phones.

          1. I like that option. I have used gaffers tape looped sticky side out to lay out parts exactly where they came out of the board / device so they don’t roll away.

  4. Hack worthy for sure. Goes to show how nasty traps are designed into products particularly those with the lower case “i”. Any other manufacturer would use standard lengths on fewer sized screws, the case design would be a little thicker and more robust yet cheaper than you know who.

    1. Try a Sony TRV-900 repair. No “i” involved. Lots of screws of several sorts. Why would this be a “trap”? It isn’t like the special factory tools needed to work on an old Triumph or Alfa Romeo. You don’t have to buy a special Apple screw driver, just maybe a tutorial on correctly operating one.

      1. “Why would this be a “trap”?”

        Because in practically every other similar repair in the world a 0.1mm difference in screw height would not cut through several incredibly tiny traces and damage the unit.

        Nearly all electronics I’ve pulled apart (including plenty of phones) do not have screws which bottom out on circuit boards in a way that could cut something critical. This is a trap in that it is causing people who have experience with repairing stuff to actually damage devices in a practically unheard of way.

  5. It’s hardly a nasty trap to use different length screws in a device!

    Various component and shields are different sizes thus necessitating different length screws. Not everything can be a proto type board scotch taped to the lid of a butter tub.

    The moral of this story is, when you take something appart it helps to have instructions (there are plenty of guides for iPhone repair). And if you can’t find them then it’s good to take pictures and disassemble carefully laying out screws as you go.

    1. I agree that being careful is always a best practice, but you’re wrong for defending Apple on this. Other manufacturers’ designs perform the same or better, and they don’t “need” such subtly different screw lengths. If it’s true that this was an honest design choice, then it’s a testament to stubbornly pretentious design.

      1. It shows a willingness to go for a better engineering and human factors solution over saving a penny to get simplicity of inventory and assembly. You are talking about some sort of engineering opposite world. Ungeneering?

        1. Since when is having three different lengths of screws, 0.1mm apart, which if accidently mixed up destroys the phone considered good engineering? You need to lay off the koolaide…

          1. You guys made good points, the first thing through my head reading this was also economical- Apple has made their empire utilizing proprietary technology that cannot be readily interchanged or repaired.

            lol@ungineering, its a funny problem: Is it efficient to use similar screws were needed or is it efficient to require many different screws in precise locations that if switched can effectively destroy the device when any average user attempts to repair the device they have purchased.

    2. Pardon me for my ignorance, but how can pictures adequately show the difference in length between screws wher th difference is smaller than the average thickness of a strand of hair? At this point, the only reliable way for one to differentiate the screws would be to color the tops of them with a corresponding dot of color on the board where that particular screw resides.

        1. Precisely! Pun intended. When I take something apart I *do* make note of screw lengths and mark or sort them accordingly, but there is no way I would see the difference between 1.2 and 1.3mm. In fact, it would seem that over tightening the 1.2mm might also cause havoc!

    3. >It’s hardly a nasty trap to use different length screws in a device!

      Well then, if this wasn’t a deliberate trap for 3rd party repair teams, Apple should now document the difference in a tech bulletin, and then anodize or parkerize or plate the screw differently from now on to avoid future mixups.

      But this is Apple, and they probably feel a little violated that you dared to intrude in the inside of their design anyway, because their ToS leaves little doubt that they don’t think you really own your own phone. Don’t hold your breath. Don’t buy Apple.

  6. 2 ways to deal with the “which screw goes where” problem:

    1) Draw whatever you’re disassembling, mark the screw holes, and tape the screws to the drawing.
    2) Rainbow pack of markers, mark each screw a different color then take a picture before disassembling.

      1. I was thinking just have a whole bunch on small, numbered bins and put one screw in each and number them on a photo of it. Slow as hell, but saves having to measure screws and simplifies putting them back in the reverse order.

      2. Differing screw lengths is nothing new. When I’m disassembling something for which I know (or suspect) this is an issue and want to be certain I reassemble it correctly, I take a photo of the device and print it out, enlarged or shrunk as necessary. Then as I remove each screw, I Scotch tape it onto the appropriate place on the photo. Repeat for each layer of disassembly.

        However, I’ve never dealt with a device where screws differed by such small amounts, and swapping them could be destructive. I can accept that such a miniaturized device requires this kind of design. And I can accept that it could be necessary for one screw to be 1.7mm, and another 1.2mm. But I can’t help thinking yellow/orange could have both been served by 1.2mm screws, and that making one 1.3mm is strictly a dick move on Apple’s part. (Which would also be nothing new.)

    1. Whenever I take something apart I always lay out the screws on a flat surface in the same ‘pattern’ as they came out of the device, often large things like laptops but a few phones & tablets.
      It’s a habit I taught myself after discovering on some of my own things if I put the wrong (long) screw in it will push into the plastic shell of the device, creating an unsightly bulge on the outside surface.

      Thankfully I’ve never had to take an Apple device apart, and never want to.

    2. Or remove all screws to an exploded view of the device. i.e. screws removed from the bottom left sit to the bottom left of the device Top right -> sit top right.

      2nd layer of screws are also stored in a exploded view of the 2nd layer – bottom left -> further out to the bottom left …. and so on.

      I have never had a problem reassembling anything ever.

    1. Hi Sam, I am most curious about the technique to cut the strips of copper and solder them. Could you please elaborate or direct to some photos of the thing ? I believe I could learn to use this to other kinds of equipment damaged to some clumsy handling …

        1. Would it not be easier to use micro brush to apply adhesive of whatever design , and then brush metal over as they would use gold foil to cover things in gold? The gold / metal foil would only stick where the glue is applied.

  7. I am a watchmaker- we have this same problem on nearly every watch we fix.
    Many of the screws have different styles of heads, and many are the same thread pitch, but 0.1 mm different in length, etc.

    Putting just 1 screw in the wrong hole leaves the screw end binding the rotation of gears, binding setting mechanism lever parts, all kinds of bad bad things.

    So from my perspective, I see this all the time, but it’s kinda inherent to the work I do.
    We get around it by inspecting each screw, and pushing screws into a piece of pithwood in the general location pattern that we take them out of the watch. This way we keep track of exact screw placement. Occasionally, measuring screws and noting their length is helpful.

    To do this with a phone, yeah, I think this is pretty stupid they made it that way. It seems like it was indeed just to screw 3rd party repairs.

    1. Thanks for sharing the pithwood idea, never used it before, but I do like the idea. Nice, very nice. And Styrofoam would probably do in a pinch as a substitution for a once off phone/table/laptop repair.

    2. Any consumer who disassembles a watch deserves everything they get, yet an iphone is a consumer product and I know people who don’t know the difference between a phillip’s head and Pozidrive who were able to successfully replace the screen on their iphones. While I don’t think Apple deliberately designed in the potential for catastrophic failure for the DIY crowd, I doubt they were ignorant of the potential consequences.

      1. Well I cant figure out why an Iphone is a consumer product yet a watch is not.

        By this definition, I might not be a consumer then. I can not pay the almost *1000% markup for technology.

        *Comparing my $200 laptop to one of similar specs of a macbook purchaser, 2 years after I purchased mine. His was $1,800 before tax. Both same screen size, cpu speed and amount of memory. While hardware designs do not make these an equal comparison, I am simply comparing the ‘sales sheet specs’ as end-users should do but obviously not even ‘power-users’ do.

        1. “Comparing my $200 laptop to one of similar specs of a macbook purchaser, 2 years after I purchased mine. His was $1,800 before tax. Both same screen size, cpu speed and amount of memory. ”
          Ahhh… No. No $200 laptop will match any macbook unless the $200 laptop is stolen.

    3. Well.. there is at least a MECHANICAL reason for that. A screw needs to have enough grip to hold firmly while not being over tightened, and to stay out of the path of other parts etc. And in such a confined space, different fixings need to be precisely chosen. It’s annoying, but at least it is justified.

      It is not I would imagine done just to make repairing and maintaining the mechanism harder. I somehow doubt there is some watch designer chuckling to himself as he specifies two identical screws, one being just different enough to strip the threads if put in the wrong place.

      But this is 100% designed in deliberate pure spite.

      No mechanical or electrical justification.

      Designing in through board holes for fixing is standard practice.
      Gluing the crap out of anything and everything is common practice.

      But a screw that in proper use gets close enough to exposed copper to be damaged if even the right screw is nipped up too tight is too bad design to be accidental.

      Personally, I hope the fail rate costs more than any money from extra sales.

      Apple.. Meet new low.

    1. Ive been asking this since they introduced the imac in the late 90’s, bringing apple back into the radar, which is, coincidentally? when the VW Beatle was reintroduced.

      I think the two problems are related: it seems almost entirely marketing.

      With apple I have yet to see anything actually new/revolutionary- just their take on existing consumer products with an outrageous price tag.

  8. The main story seen by me- is waay more about the make it fixed chops needed to fix such traces.

    I’ve used allsorts of bodgy jumpers and even solderwick to patch traces murdered by stupidity. Often becoming so barbaric as to wrap jumpers around leads on the component side of a board for timesaving. Because sometimes Good Enough- Is.

    Sam’s way more elegant approach is Leading By Example. Salute!

    Back to the DesignFail and queries of screw management by techs. DEcades ago I’d had old magnetic car signs taped down on my benches for laying out bits that it worked for. Damnably many screws today, especially in fruitstuff are non-magnetic! Which also sabotages many of our tricks. I’d almost consider this worthy of rethinking owing any stuff so designed. Maybe we need to say that more?

    Yeah- it was broken by an indefensibly *stupid* design indeed worthy of denouncement in it’s own post… but still&all it underscores why Hackers need to question suchlike. Proven stuff like this raises a question. Why is sexy UI/Handfeel design is more valued than common fracking sense?

    So this is one more reason for my NOT OWNING NOR RECOMMENDING “Anything” made so stupid.

    Most, if not all sane designers budget the prevention of such fails into every needful detail.. I certainly do by laying out stuff to make such fails damnear impossible. Though there were/apparently still are the reverse mindspaces. .

    Decades ago there was an incredibly SciFi AlienTechBoobytrap in High End Audio units where a TEMPERED GLASS circuit board had LEFT HAND THREADED MOUNTING SCREWS= Guaranteed Board Death for those not warned.

    Apple’s Screwing us into apparently similarly designed in death is just one more case of the same. Where stupid or greed makes no difference. I will be eversomuch moremindful to not even think of letting Rotten Fruit into my life. And iRepairNational gets a mountain of Skulls if there’s any justice.

    1. Heh, That KS is actually worth a read just for the lulz.

      – “We also tested the air umbrellas on rainy days. ”
      – “After a year’s hard work, we finally improved the appearance of the umbrella which may influence the effect.” (Yup, better looking ≡ more functional.)
      – “Does it blow water into other people standing nearby?
      Big and fast raindrops will be blown to a near distance while those small and slow raindrops will be blown to a farther distance. Also, nearby pedestrians will also take umbrellas if it is raining heavily. In this way, the rain will not be blown to other pedestrians. If nearby pedestrians do not take umbrella and close, they will be affected more or less [sic.], but they will get wet in a rainy day if not taking umbrella anyway.

      What’s worrying is that I think these guys actually believe this might be a practical item. I can only imagine a rainy day in London with the entire of Oxford Street walking around with these useless, noisy (think Dyson air blades…) contraptions.

        1. Out, Out [with your wallets], you demons of stupidity! Damn. That was 20 years ago. I feel old. I don’t know whether to thank you for the reminder or curse you for the realization!

      1. Reminds me of the ‘features’ listings on wholesale Chinese sites and sometimes cheap product packaging. I do feel that the marketers believe this is just as legitimate as that $1.99 spy cam.

        +Size compact
        +Pleasingly aesthetic
        +In Box

      1. I never said I am intelligent.
        The proof? At one point in my life I had an Apple computer:)

        btw: too lazy for getting used to dvorak then switching back to qwerty when not at home.

  9. If anybody thinks iPhone 4 screen repair is a pain because you have to remove 3/4 of the phone to get to the screen try doing a chassis replacement for an iPhone 5. Sure, the screen replacement for a 5 might be quick and easy but to rip and replace everything in the chassis you’re in a world of hurt. Some things are gummed down (not screwed) which makes them difficult to remove gently and difficult to stick down in their new home.

    Even worse, some things are screwed in with *teeny tiny* little screws that are done up so tightly that you strip the head of your screwdriver (yes, I am using the right size and lots of pressure!) before the screw budges. Before now I have never stripped the head of a screwdriver before the head of a screw.

    I use some big flat fridge magnets to lay out the screws and small pieces in order/grouping that I removed them and I take note when a particular screw is infinitesimally larger than the other.

  10. I parted out a last revision aluminum PowerBook G4. The over-complexity and amount of excess parts in it was just insane. Parts that in any other brand of laptop would be on the main board were separate components. Every sub-component was connected to the main board by a flex cable. In any other make such components would have connectors that simply plug together. Even the hard drive is connected by a fragile cable just like on the old 68K CPU PowerBooks. Almost all other brands and models just plug the hard drive and optical drives directly into mating connectors on the main board.

    Once all the innards were out I found a cast metal (magnesium?) frame screwed to threaded posts that appeared to be welded to the thin metal shell. Why not just glue the frame in or use a cast magnesium shell with all the mounting points formed in, like Samsung did on their X65? (AKA the mpc TransPort T2500.)

    Apple build their products as if they’ve been designed in the universe of Frederik Pohl’s “The Midas Plague”.

  11. I was once asked how I would create a sneaky anti-tamper feature for a device.

    I told them to do what I once recommended for a critical medical device. Just place
    a SM LED on the circuit board and if it ever detects any ambient light just set a flag in the flash that disables the device. This device was always on (as are most things nowadays) and had an internal battery that provided backup power to an ARM that was in sleep mode most of the time. To service the device you had to kill the lights just before removing the cover and send a sequence of light flashes with a hand held device to tell the device it was being serviced and to turn off the kill switch.

    In a commercial device like a phone this would be a dick thing to do…in this case however it was absolutely required for safety.

      1. The ARM was already there as one of the watchdog devices that monitored the device for safety and the LED was also already there for blinking out diagnostic data to servicing it cost nearly nothing to add the functionality. A switch would have been rather obvious also.

    1. Cool, I absolutely like the unuspiciousness of this approach.. LED and ARM already there, the booby is in the software alone. Brilliant. Not even x-ray would get this before the fact.

  12. (Slow clapping) Bravo Apple, Bravo. Customers shouldn’t b repairing products they have bought, they should buy NEW PRODUCTS! Putting a repair self-destruct into your products is a stroke of genius! Show those hackers were to get off, all they should do is facebook, twitter and download overpriced crap off iTunes, and of course if they stupidly break their toys pay you through the nose for a new one! Steve Jobs is smiling in hell.

  13. Yeah, ran into that before.
    The 4S is infamous for booby traps and one particularly sneaky one is the use of a hidden fuse that blows if the wifi chip internal power shorts causing black screen but backlight on.
    Only fix is motherboard replacement and that can be crazy expensive.

    (any ideas where this is, because I can’t find it anywhere on the board)

    That and the use of special batteries that contain sneaky @ppl£ code so they can’t be used in anything but another 4S and output no power to any other device even if the connector is transplanted. Oh and stop working permanently if they drop below 3.5V

  14. There’s a great resource, They sell tracks and pads with a heat activated epoxy backing. You cut it to length, place it properly, apply proper heat and pressure to bond it to the circuit board, and then solder it as normal. I’ve used this to replace a torn up 0.8mm pitch BGA pad (0.33mm diameter pad and 0.146mm width trace).

  15. Wow, a lot of you need to lay off the crystal meth, its kind of making you paranoid and delusional.

    Apple is sabotaging DIY repair of its products? I think I’ve heard it all now…

    I have no brand allegiance when it comes to anything, but I tend to notice the apple haters come out in droves – where I rarely see apple fan boys going after android with this kind of vitriol.

    Get over it, some people like the competitors products!!!

    It’s exactly why you pay LESS for the product you happen to like, But we should all carry one brand of OS on our phone because THAT’S good for the consumer….

    We are talking about a full on computer small enough to fit into the palm of your freaking hand, no matter who makes the hardware, and it’s come to this? Nit picking the fucking screws in the thing? So this is the future, full of a bunch of jaded, immature, super critical, asshole, trolls. Who would have thought…?

    I think a lot of you watch from the side lines, but have never taken anything apart, because if you had, you would find that all sorts of shit has different size screws, and yes, even barely different sizes that will fuck things up if you put it back together wrong.

    As others have pointed out, CAMERAS are a big one, so are watches etc etc… But if apple is guilty of it, look out… As if google has clean hands in anything.

    You dicks would be almost funny if you werent so sad….

    1. Cameras and watches are mechanical though. There is a very legitimate reason for those screws to have such tight tolerances. The iPhones is a digital device though. What moving parts require the .1mm difference? I could be wrong though, the next step is for somebody to see if they can reassemble using only the short screws.

    1. After finishing the first one of these board repairs, recreating a top down color coded screw reference photo was the last priority on our list ( thanks ifixit! ) . However, if you had read the blog you would have discovered that this particular iPhone was brought to us with the screw damage ( surprisingly, from another repair shop not a DIY repair gone wrong ).

  16. It really depends on how many you repair. If you can make it through the first one without jacking it up, you can tell by sight which screw goes where. Like any kind of mechanical work, repetition is the key. So definitely not a good idea for any old hack to give it a try.

    1. Even with my digital calipers, a .1mm difference is difficult to notice. I don’t see how repetition of going to improve your eyes. The more times you do it the more chances you’ll have to misplace that ever so slightly smaller screw. As other have already said, color coating is the way to do this. And if you’re doing that, you shouldn’t have any problems, even on your first attempt with no experience.

  17. Man, I’m sorry to hear that you used the wrong screw and broke your phone! It seems to me like you probably should’ve let a professional fix your phone. Hopefully you’ve learned your lesson and you won’t make the mistake twice!

  18. ive put the wrong screw In the wrong hole of a mates iphone 5 :(

    Thanks to people who have taken the time to post things like this hack I am part of the way through attempting to repair the damaged tracks.

    Needless to say it is a hell off a challenge. Here’s hoping I can pull it off.

    im pressing on with the challenge and despite the potential that my repair will be unsuccessful. But how cool would it be to repair something that nobody can actually even see.

  19. There’s no way they control the screw length tolerances to something tighter than +/-0.1mm. Those are not 2 different screws, they are the same screw with normal production variation in length. What is more likely is that you over-torqued that screw and that increased the engagement depth enough to contact the PCB below. In other words: a poor design. I think we’re giving Apple too much design credit here to think that they intentionally sabotaged it by trying to work in a slightly shorter screw. There are easier ways to make it un-serviceable.

    1. >There’s no way they control the screw length tolerances to something tighter than +/-0.1mm..
      Way.. there is no public access to ISO 1501 but here is some excerpt for you perusal: I found by googling for it.
      They have the control for the outer dimension of the thread for M1.4 to M0.3 down to +/- 0.015 mm.
      So don’t be surprised when they can control the length of these screws to at least +/- 0.025 mm..

  20. Strict uniformity is the only answer to the situation regarding screw lengths in the iPhone range of products coupled with a micrometre at the ready to make certain the screw you are using is the correct length. I set the micrometre at the specified screw length lock it in position and test the screw in the gap with a pair of fine tweezers.
    I had a 4s in for a new screen today on opening the phone it was obvious that parts were missing etc. the phone had been elsewhere.
    I removed one of the screws of critical length and yes you’ve guessed already, a screw length of 1.66 had been used where a1.37 should have been used, definite blue screen situation, needless to say I had to refuse the screen replacement work.
    Happy days with the Apple products.
    Neil Rodgers

  21. This is just one example of how precise phone repairs need to be. My friend tried to fix her phone at home and ended up needing a replacement rather than a repair. I would suggest either taking great care and exercising patience, or hiring a professional company. As mentioned, these screws differ by just fractions of a millimeter, but mixing them up can be very harmful. Thanks for the article!

  22. I have just “repaired” my daughters phone, I didn’t mix the screws up, however the phone won’t boot up at all, with or without the screen attached. Any ideas what can cause this as I’m baffled by it. I’ve repaired plenty of these without any problems

  23. Hi, there seems to be a similar bug on the 4S if you use an aftermarket WiFi/BT chip.
    I tested this by removing the chip and the problem goes away until the next firmware update :-(
    Evidently Apple are bricking 4S’s that fail in this way rather than simply showing a message advising
    people to replace/repair their phone on each cold restart which would at least be fair.

  24. Hi Guys before you send your phone for repair or throw it away try what I did:Take all the screen cover screws out. Disconnect the battery. Disconnect & reconnect the screen/touchscreen/home button connectors & lastly reconnect the battery. Try it now before you put the screws back. If it works now put the screws back in the correct place! (tip – place the screws on their heads next to each other & you can see the different lengths).I’m guessing the wrong/long screw cut into the pcb & made a short circuit without actually breaking the track. Maybe this will help someone?

  25. Are you REALLY sure that it was 0.1 mm difference in THIS case? I ask because I disassembled a assembled a lot of 5S, and I’m really, really sure that I mixed up these 1.2 and 1.3 screws in some cases, but never had a problem with it. I even tried to categorize these screws to avoid mixing them up – but I was not able to measure them with my old caliper to really say for sure which is 1.2 and which is 1.3 mm. So in my experience, there was not any harm done by mixing up these two lengths.

  26. The easy solution to the problem of accidentally mixing up the screws is to line them up on a table upside down from biggest to smallest. We know the largest screw involved with the screen replacement is a single 3.2 mm, and the smallest are three 1.2 mm. Then there’s two 1.9 mm so finding them will be easy. And the rest are one each so from there you can figure out the next size up from 1.9 mm, which is 2.2 mm, and after that 3.1. mm, which is one or two threads smaller than the largest 3.2 mm.

    You can also use a jeweler loop to count the threads on each screw if your eyes aren’t good enough to see the difference in sizes. But the size difference is pretty noticeable once you line them up next to each other.

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.