This test shows a severe lack of understanding of flexural strength testing. This test is a bastardization of the three point bending test that is commonly performed for peak bending strength analysis of materials.
Bending is a result of moments and moments are driven by moment arms. These tests should not be looking at point load required to induce deformation but rather the moment required to induce deformation. Each of these should have been converted into equivalent moments based on the size of the phone.
For example, the M8 is shown as 146.3 mm (5.76 in) H; 70.6 mm (2.78 in) W; 9.4 mm (0.37 in) D and the iPhone 6 is 138.1 x 67 x 6.9 mm (5.44 x 2.64 x 0.27 in) and both are shown to "deform" at 70 lbs.
The M8 has an induced moment of 100 lb-in while the iPhone 6 has an induced moment of 95 lb-in. The resultant bending stress by assuming a linear stress distribution across the section is then 1575 psi for the M8 and 2950 psi for the iPhone 6.
Similar analyses should be undertaken for each of the other phones.
A more accurate test for the failure mode of concern would be a four point load test in which moment is constant across a portion of the phone. The three point load test induces a moment that is maximum at the point of load application. The four point load test is more likely to show you where the point of weakness in the phone is.
So what does this ultimately mean? Seems like you can bend any given modern smartphone, given enough force. Is the iPhone 6 more likely to bend under average conditions? Is there any substance to the hubbub about bending 6's? A lot of jargon in your response, is this lengthy response just to point out that their methodology is flawed or are you making a point about the case at hand?
The point of my response is that the test performed does not test against the complaint, it is a manipulation of the data (either through ignorance or malice) that presents data that may not truly imply the conclusion drawn by the article.
Phones are composed of many different materials of many different sizes and shapes at different points through its cross section. When looking for a "yield force" or "rupture force," as this article does, the three point test is effective ONLY for materials which are constant along the entirety of the test section or for parts where the loading condition is replicated exactly. When the loading condition may be unknown or the sectional properties may vary along the length of the phone then the four point test is more appropriate as it will show you the bending moment that is required to induce yield/rupture and, more importantly, it will show you WHERE that point is.
Most people elsewhere in this thread note that the point of weakness appears to be at the volume buttons on this phone. The three point bending test where the phone is loaded in the center may or may not reveal this, but a proper four point bending test would. Proper analysis of the testing method, reported failure modes, and the testing data would reveal this.
I also take a little exception with the "70 lbs is what it takes to break four pencils" demonstration they do as it is misleading and not informational at all. Four pencils loaded with 70 lbs at what point? What is the geometry of the four pencils? Is it 2x2 square or 4x1 rectangular? Which direction is it loaded?
The whole article stinks of pseudo-science which is what you get when you have journalists conducting tests without consulting with a proper expert in the field.
The article notes that the three point test is the "standard" that Apple uses for this type of test as if it somehow makes that the appropriate test for this type of analysis. It does not.
My attempt at a "for dummies" summary of the issue here:
If you look carefully, the Consumer Reports tests involve placing end supports roughly 1/4" from either edge of each phone. Basically, all the phones are different sizes and thus have varying amounts of material and torque being applied between the supports and the part of the machine pressing down. A particularly long phone which yields at 70lb of force has actually performed better than a stubby one which yields at 70lb in this case. Hopefully I didn't just say anything too wrong or confusing, because I'm not going to notice until the morning...
If any phone is going to be subject to the same force at the edges, regardless of length, then that's what you want to be measuring. It doesn't matter if a long phone can handle slightly more torque than a short one, if it's going to be subject to a lot more torque.
I don't know what the stresses applied to a phone in a pocket actually look like, but it's not obvious to me that measuring force rather than torque is unfair.
This isn't a test of the materials though, it's a test of the phones as a whole. When I sit on my iPhablet it's going to have more leverage working against it than an iPhone 5.
Woah, that's pretty amazing. And I think, (strange as it might seem) ultimately more informational than the consumerreports tests. Don't know why you're getting downvoted.
"But it's thinner!" Meanwhile, everyone seems to want a more durable phone / more battery life. The result is cases which can easily double the total thickness of the phone just to protect it. I personally miss the OG Droid / HTC Windows Mobile phones that could take 2 years of beating and still be going strong. I'd gladly take an iPhone 7 twice as thick as the 6 if it was waterproof, droppable from 10ft, and could last 16 hours of heavy use after the battery had been abused for 2 years.
I don't think this is very in-tune with the actual buyers.
iPhones always outperform Androids in battery life in the real world IME (there are exceptions that probably break the rule, but with compromises elsewhere I'm not willing to make so I haven't bought those devices). My 6+ is living up to the "2 days" claim.
I absolutely wouldn't trade thinness, and more importantly, weight, for longer battery life.
The battery life is fine. The weight is good. The thinness allows me to add a case and still only have it be as thick as an iPhone 5.
For me, someone who actually paid for an off contract 6+, they made the right call.
Nope your argument doesn't follow from parent's point.
Parent is saying people want durability and better battery life and would gladly sacrifice thickness for it, not sacrifice all the things that iPhones have and those old Nokia's didn't.
It's a false dichotomy, either an iphone 6 plus or a nokia? Give me a break.
I'd happily take the iphone 6, add 20-40% in thickness and weight, make it more durable and have a bigger battery, and let the phone sit flat on a table (as opposed to the camera sticking out like now) without having to mess with a case.
Actually I want a more reparable phone. I'll sacrifice thickness if it means that the LCD, digitizer, motherboard and chassis could be separated by just undoing screws and cutting a seal (iPhone 3g's I took to repairing bby remaking the seal with polyurethane each time).
Civil Engineering Grad student here. Agreed, four point load test allows for uniform bending moment distribution between the two loading point. Which can expose the weakest point in the phone (in iPhone6+ near the volume buttons).
The link below is the moment diagram for both load test.
http://images.slideplayer.us/5/1566057/slides/slide_20.jpg
The Youtube video made by the guy who bends the 6 Plus with his hands shows that the weak point is at the volume slot. I think its a bit disappointing that ConsumerReports didn't go into more detail.
They also didn't respond to the suspected weak spot near the mute and volume buttons at all. I could imagine that this spot was not under a lot of stress the way they bent it.
I completely disagree. This is a case where the size plays a significant role in how it would be bent in real life. Strongest for its thickness isn't worth much. My cheek pressing in the center of a phone while I sit on a soft couch loads the full length, and approximates the 3 point test quite well.
Physics is done quite readily by using a consistent unit system of pound inch second or kip feet seconds. All of these units can be converted to metric; however, it appears that one of the key characteristics of metric system champions is an inability to do conversions and so the convertiblity of any units may a moot point.
No it's not quite the same, the fact that all the conversion factors between ft and in and lb and oz are weird numbers rather than power of tens means that if someone gives me a weird compound unit (for example forces and distances in DNA are measured in piconewton and nanometer) I can't do the math in my head.
tl;dr the point it's not the fact that it's metric, but that it's decimal.
"Not it's not quite the same"? What is not the same? Converting between metric units and English units? It's exactly the same if you're doing it right. Contrary to common belief, most engineering and science that is done using the English system doesn't use "eight pounds four ounces per foot per inch" or some other such silly unit. Consistent units are used based on the application. Are there instances where a conversion must be used? Certainly. Are these conversions any more complex than those used in the metric system? No.
Disagree? Then tell me how many liters of water are needed to fill a cubic meter of space without looking it up or writing it down. You can't? Then stop crying about having to divide by 12 to get to feet.
Only an idiot does unit conversions in their head.
> Then tell me how many liters of water are needed to fill a cubic meter of space without looking it up or writing it down.
1000. I had the answer calculated in my head before I finished reading the sentence. I knew that conversion by heart before I was 10. Also as a grown-up my water usage is billed in cubic meters of water used per month.
This video is all you need to see why using imperial for anything is idiotic: http://youtu.be/EUpwa0je6_Y - this is a group of people who use imperial measures daily struggling with a basic arithmetic operation that any second grader could solve in metric.
Actually, with metric units it's pretty easy: 1,000 liters of water are needed to fill a cubic meter of space. That's because in the metric system 1 cubic centimeter is equivalent to 1 milliliter.
It's too bad there isn't an educational system that exists to help us learn units throughout childhood so that we can apply them to everyday tasks in our adult lives.
Bending is a result of moments and moments are driven by moment arms. These tests should not be looking at point load required to induce deformation but rather the moment required to induce deformation. Each of these should have been converted into equivalent moments based on the size of the phone.
For example, the M8 is shown as 146.3 mm (5.76 in) H; 70.6 mm (2.78 in) W; 9.4 mm (0.37 in) D and the iPhone 6 is 138.1 x 67 x 6.9 mm (5.44 x 2.64 x 0.27 in) and both are shown to "deform" at 70 lbs.
The M8 has an induced moment of 100 lb-in while the iPhone 6 has an induced moment of 95 lb-in. The resultant bending stress by assuming a linear stress distribution across the section is then 1575 psi for the M8 and 2950 psi for the iPhone 6.
Similar analyses should be undertaken for each of the other phones.
A more accurate test for the failure mode of concern would be a four point load test in which moment is constant across a portion of the phone. The three point load test induces a moment that is maximum at the point of load application. The four point load test is more likely to show you where the point of weakness in the phone is.