Anyone have any experience with self-cracking Inspiron 13 7347 screens?

I bought an HP Spectre x360 last year that exhibited this behavior and I decided not to replace it with a computer that would do the same thing but I just stumbled on a post in the official Dell forums that says this same issue can happen here!

Any way to mitigate this from happening? Should I buy additional coverage for the computer? Because whenever it does the manufacturer tries to blame the end user for something they didn't know would happen.

 

Care to elaborate/provide a link or two?


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http://en.community.dell.com/support-forums/laptop/f/3518/t/19648138

Basically you shut the laptop and leave for awhile then when you come back, cracks appear even though you weren't interacting with it.

I've speculated this happening to my Spectre x360 being the result of thermal changes (the screen is cold while it's up but when you press it up against the warm body of the computer, the heat causes rapid expansion and the stress fractures the screen).

It seems a lot of Ultrabooks are susceptible to this (I found forum evidence that Lenovo Yoga 13s also just crack out of nowhere). Seems troubling.

 

In my 15 years of owning laptops, I have never seen a screen crack because of temperature changes. I've had laptops go full throttle after being outside in the car @ -30 degrees (love the winters in the Rockies) and not a single one has cracked. Only time I've seen cracks on screens are when people are rough with them, it seems especially problematic with the metal chassis and ultra thin ones. They are so thin and the tolerances are so tight, that if you mishandle it in any way, things break. But if you're having this problem, accidental damage protection should be considered.

 

Well judging from the post in the Dell forum, it's the digitizer (touch screen panel) that has cracked, not the screen panel (which shows the image).

An example of screen panel crack:

As you can see the panel doesn't fully show the image.

An example of digitizer crack:

There are cracks on the glass, but the image shows the image well, since the screen panel isn't damaged.

Usually the digitizer is glued to the lid, and when the lid expands due to heat, the digitizer will also be stretched, and we all know glass is a brittle material... so yeah it's possible to crack the digitizer just because of heat. (In fact this is one of the common failure on laminated composites)

The screen panel is usually screwed to the lid through the holes on the metal braces covering the edges of the panel so it's not as susceptible to cracks as the digitizer, I haven't seen a screen that cracks due to heat.

 

It may be a failure mode for laminated composite materials, but I'd argue it's poor design if it's actually occurring here.

They should use a compliant glue to let the dissimilar materials to thermally expand at different rates (bear in mind the distance something the size of a screen actually grows and shrinks is probably 0.0015"). Rates of thermal expansion are well known and easily testable. The stresses induced by this amount of growth are probably on the same order as those induced by opening the lid roughly and twisting it slightly.

In product design you also design in tolerances, so the screw holes should have a few thou of play in their size and location too.


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That's not exactly true. The first picture demonstrates a failure in the LCD substrate (aka the glass within the LCD). The second picture shows an intact LCD but the protective layer/glass is cracked. Judging by the fact that it has a spiderweb appearance, its not unreasonable to assume a direct impact.

Also, "glass is a brittle material" is also not entirely true. It depends on the process in which the glass is made. Typical soda-lime glass is brittle, but most ion strengthened glass is actually quite flexible, they can take a fair amount of abuse before failing catastrophically. It is indeed possible to crack glass from heat, but the only likely scenario where that occurs is when the glass experiences significant temperature delta in a very short time. One of the most common failure on laminated composites is actually known as fibre/matrix interface failure, which essentially happens when the "glue" separates from the fibers (or sheets of other materials) causing a significant deviation from the designed specifications, ergo, failure.

As for the touch panel layering, most conventional designs sandwiches the digitizer between the LCD and the protective cover glass. Some are glued, most aren't (smartphones are somewhat of an exception). Moreover, many manufacturers (Dell included) tend to use a gasket or a frame to shield the multi-layered screen assembly (not just the LCD) from directly contacting the casing (metal or plastic) to prevent damage by the moving the casing/lid. Additionally, even if the layers were glued together, differential expansion would not result in these types of cracks because of a few reasons. One, optical adhesives used for displays is a very flexible material, it has a similar consistency to what they use to glue new credit cards to letters. Two, glass' expansion coefficient is below that of those of typical metal alloys and plastic composites, which mean that the casing typically expands more than the glass, which is also one of the many reasons why the glass will not "hit" the casing causing "self-cracking".

All said, you should really consider that almost all commercial products have to go through FMEA (failure mode and effects analysis) for whatever reasons (monetary or regulatory, remember, products that fail cost money to replace and it tarnishes brand name and value).

As alexhawker have said, if this actually happens, it'd be poor design. We often joke in the office that our greatest enemies as engineers are designers and accountants. The first wants to make everything seamless, thin and pretty. The second wants us to build it as cheaply as possible. Proper engineering is expensive, which means, you get what you pay for.

TL ; DR -- Things don't mysteriously break on its own. Your options are either abuse by the end user, or exceptionally poor design.

 

That's true, I rarely heard glass cracking or breaking into pieces just because of heating, though it's possible if there's not enough tolerance. Though I'm not surprised if it's the poor design or tolerance that causes the glass to crack, considering manufacturers nowadays prioritize form (thin as MacBook) over function (reasonable durability), and the degrading build quality on laptops. It's like that you have to treat them like babies in order not to break them.

P.S. Such a shame that even the Inspiron line couldn't hold its reputable build quality now, I had an Inspiron 6000 before and it was built like you stomped hard on it as if you had to brake in emergency, it'd still hold the shape well.

 

Well you have to keep in mind that these things are commodities. They'd have to get people to buy the latest and greatest every year in order to get they stupid profits that they're making. The most ideal situation is that they break 366 days after sale, then you're forced to buy new. But since America is unique in that we have class action lawsuits, the manufacturers have to be especially careful that they can't specifically engineer things to fail on specific dates (except HP, they put stupid expiration codes on ink cartridges, there was a whole uproar about it a couple of years ago).

Design and marketing firms have shifted heavily towards metal and glass builds for a reason (everything from electronics to buildings). They tell you that its premium materials and whatnot, but the actual goal is to make merchandise more fragile and prone to breakage (thus needs to be replaced sooner and more often). Too bad that most people don't realize that there's nothing premium about soda cans and window panes, as a matter of fact, properly spec'ed plastics are far better choices for mobile applications than metal and glass. Prime example of what plastic can do would be LEGOs. When was the last time you broke a LEGO brick? How about the last time that LEGO brick broke your foot from you stepping on it?

EDIT: Forgot to mention, best way to get good products back is to vote with your wallet. If you think its not worth your hard earned money, don't buy it. Hell I haven't bought consumer products for years, minimum is business grade since the support makes up for the lack of quality.

Also, I wouldn't bother with Apple products at all. Mostly because they have nearly zero ventilation, use substandard components for the main power rails, and they like to vent hot air onto a screen that is glued on with heat sensitive adhesives. /facepalm

 

Fortunately that won't work with me, I will only consider replacing computers after 5-8 years of use so I always demand reliability when I buy a new computer. Otherwise I'll fix it (as long as parts are available) in order to make it pass the period. If the computer can't make it in the end then the manufacturer won't get my money in the future.

And can't agree more with the business laptop part. Last summer I put my 3-year-old Fujitsu Lifebook LH772 on a 1-year suspension and replaced its role with a much older Dell Latitude E5510, as the Fujitsu was falling apart and looked like crap after 3 years of less-than-stellar care.

I know it's as stupid as picking a Skyline GT-R R33 over a GT-R R35 for a drag race, but it's been a year and I'm glad I did, not a single dent or crack on my Dell even with a few drops from the desk.

Oh too much off-topic...