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> you can see where you they are engineered to fail Really? Please give an example. I have been hearing this for at least the last 15 years and have yet to fin

> you can see where you they are engineered to fail Really? Please give an example. I have been hearing this for at least the last 15 years and have yet to find someone who can offer an example of anything that was "engineered to fail" when challenged. Not saying it doesn't exist, but I'd just like to see a single example of it happening. Sacrificial parts that are designed to fail in order to mitigate a more serious failure do not count for the purposes of this request -- that's just Good Engineering Practice.

deaddodo 3y ago
I think people should rephrase it to "not engineered to last/repair". This is a much easier metric to point out and is about equivalent (though, less nefarious) to what they mean. If you use that metric, it's insanely easy to quantify. Just look at the average refrigerator today, compared to one from the 50s-70s. It's a fraction of the cost, but it's built from cheaper/less reliable parts in a repair-unfriendly (but quick to produce) manner. The idea being that you'll buy a new fridge every 8-12 years and recycle (ideally) the old one, versus spending the cost of a car on one and keeping it for a generation or two. This is what planned obsolescence means, usually. The only nefariously intended to "break" items that I can think of are electronic devices that are unrootable and rely on third-party networked services.
- HeyLaughingBoy 3y ago
  Oh, I completely agree with you on that. Most consumer items are built to a price point. If you're building to sell at a low price, you have to keep Bill of Materials cost low to make selling the thing worthwhile, so it's not surprising that, e.g., a cheap riding mower is made from thin stamped steel chassis whereas a commercial one is mostly heavy weldments that hold up to being banged around for hours each day. I'm not being difficult. When I read "engineered to fail" that's not the impression I get from the statement.
  - derefr 3y ago
    Honestly seems to me that some BOMs (and therefore some practically-achievable price-points) should be illegal, then. You shouldn't be allowed to market something as a mower, if it's built such that the act of mowing gradually shakes the mower apart. Yes, a change like this would mean that, in the short term, there'd suddenly be no "consumer" version of many products. But that'd only be the short term. In the medium term, I'd expect heavy pressure for innovation in materials science, with all these companies that were fine with plastics before, suddenly investing money and labor into operationalization of e.g. scaling carbon-fiber production.
    - ultrarunner 3y ago
      This sounds like me like an inquiry into "quality" and an attempt to make illegal those products lacking a certain quality. I generally call these products "<thing> shaped objects", e.g. a helmet shaped object that has all the outward appearance of an actual helmet, but does little to protect the wearer in the event of a crash. "DOT standards!" you might object, but DOT is generally known to be the worst standard in the world, often holding the industry back instead of moving it forward. If the department of transportation is unable to properly regulate safety equipment like helmets, I'm not sure I expect better results from a government committee intended to regulate the quality of nearly everything. This, of course, assumes that one can not only define "quality", but determine a threshold on a spectrum that delineates legality. Or maybe we'll just accept Tsars that "know it when they see it."
      - derefr 3y ago
        Yes, there is no general definition of "quality." But every industry and product has its own internal, domain-specific definition of quality. For hard drives, "quality" is MTBF. For batteries, "quality" is measured in loss of charge capacity per charge cycle. Or let me put it this way: the commercial/industrial versions of these products do some things differently. Why do they do those things? To increase "quality." If the industry didn't know what its "quality" metric was, then it would be impossible for them to make the commercial/industrial product "better" for long-term commercial/industrial use than the consumer one. In any industry where the commercial/industrial version of a product — one that lasts decades in heavy use — is already an existence proof for the possibility of "quality" in the product category, you can simply regulate that the consumer version must also be made to last at least N years of regular consumer-duty use. Doesn't matter how they accomplish that. Maybe they can't accomplish that, with positive margins, at a price point anyone is willing to buy, at first. Oh well. Keep trying. Compare/contrast: FDA stage-3 drug trials — the trial phase that tests drug efficacy. It's up to the drug's manufacturer to declare to the FDA what effect the drug is supposed to have — it's the very same effect the company is applying to the FDA to be able to market the drug as having. An efficacy trial, is simply the FDA demanding, from a drug's manufacturer, proof positive of its own planned marketing claims about the drug. That efficacy proof uses metrics specific to the pathology that the drug treats — and likely metrics invented by the drug manufacturer themselves, while researching the problem. But crucially, the manufacturer, before even starting the trial, has to convince the FDA that these metrics are sensible ones to measure efficacy by; and also has to work with the FDA to reach a consensus on what would constitute a satisfactory level of efficacy for their drug (i.e. what metrics thresholds are meant by a marketing claim like "relieves headaches.")
nivenhuh 3y ago
Kitchen aid stand mixers converted from using metal gearing to plastic gearing in their consumer stand mixers. After a certain amount of use, the gear wears out and costs $50 for a replacement. The commercial line still uses metal gears. The maintenance on it is to check grease/lubricant after a certain amount of use. (We used the stand mixer daily. Our home edition lasted 6-9 months before needing a gear change. The commercial edition has been going strong for a few years now.) I’m sure there’s a reason why they moved to a fail-safe gear for consumer use — but as a consumer — I have no clue what that reason is. (We do ask a lot of our mixer tho!)
- aeyes 3y ago
  Does the plastic gear break if you attempt to recreate "will it blend" videos at home? They probably try to sell this as a safety feature.
- HeyLaughingBoy 3y ago
  I have one of those mixers and I've replaced the sacrificial gear at least 3 times, although I usually get the gears for far less than $50. I gotta learn to not overload it with bread dough :-) Based on what I see when I open up the unit, the reason they don't have an all metal gear train is that doing that would impose the need for higher strength on everything in the transmission and the chassis up to the motor. That would increase the cost to the point where it would cut into sales. The larger consumer mixers (6qt?) are built more heavy duty since I know that they can take a larger vertical load, but I don't know if they also have the nylon gear.
  - winrid 3y ago
    They can use glass reinforced plastic instead, and powdered metal or nylon gears like the mid range $150 consumer drills...
    - HeyLaughingBoy 3y ago
      I think I may have misunderstood GP's post. I thought they meant that one of the gears was changed to plastic (as in mine) with the rest remaining metal. But it's more likely that they meant that the newer models are now using a fully plastic geartrain based on what I've read since.
mrguyorama 3y ago
>Sacrificial parts that are designed to fail in order to mitigate a more serious failure do not count for the purposes of this request -- that's just Good Engineering Practice. Except when that part breaks and the company does not make replacements available and the product was not meant to be taken apart to replace it. Mechanical fuses only work when you can easily buy and replace the mechanical fuse and ALSO fix whatever caused the failure in the first place. Otherwise it's just a weak link.
- HeyLaughingBoy 3y ago
  Yes, but. That designed-in weak link that you can't fix could be the difference between you being pissed off because your machine doesn't work anymore and you losing a hand.
  - winrid 3y ago
    That's just not the thought process. A vacuum with a cheap motor isn't going to have trouble hurting your fingers if you stick them in the brush at the right angle. But the bearings will wear out in 5 years. Another is drills with cheap housings or gears. The drill will happily rip a glove off and de-skin you. But it'll still wear out faster than if it had metal gears or a tougher housing. Usually safety is an expense. Extra sensors, very carefully engineered weak links that suddenly break under load. Another counter example to your point is my automated litter box. It has a pinch sensor for safety reasons, which is made of two metal contacts. This sensor is directly above the pee/poop so it corrodes and I have to take out like 20 screws in a machine filled with poop to fix it, like every year. They could just have added a plastic cover and one screw to protect the contacts, but no. Probably the only thing I can think of to support your argument is cars. The front end of a car is plastic and metal designed to absorb energy in an impact. But household stuff...
kortex 3y ago
I owned a treadmill (second-hand, details long forgotten, sorry) which had two long steel rails (running the length of the machine) for the main structure. The brackets which connected the rails on the front side were steel, but the ones on the back of the machine were inexplicably plastic. There were major load paths (cyclical loading from running) going straight through these brackets to the feet. Between the wear and plastic embrittlement, these parts were the first to fail, and the entire rest of the machine was in decent condition (easily years of life left). There was nothing particularly complex about that part, they could have easily used steel brackets. I can't help but feel like it was designed for a specific lifespan.
aubanel 3y ago
The father of a friend worked at a high position at Canon. For a specific enterprise command, the client company wanted printers with a lifetime 20,000 copies instead of the base 10,000. Canon went "no problem, we'll see with our engineers" and actually they only had to remove a small device which was basically a print counter and would artificially block the ink input at approx 10,000 copies. So nothing to do with good engineering, only bad business practices.
winrid 3y ago
Usually by using very cheap bearings which last just past the warranty period and cheaping out on reinforcement in critical areas. The AvE YouTube channel covers lots of this with his BOLTR teardowns.
deelowe 3y ago
> Really? Please give an example. I gave you one already. Newer stihl trimmers removed the grease plug. It's impossible to lubricate the trimmer head and they predictably fail after so may hours. A replacement head costs nearly as much as a new trimmer. The head is the most common part that fails on trimmers.

deaddodo 3y ago

I think people should rephrase it to "not engineered to last/repair". This is a much easier metric to point out and is about equivalent (though, less nefarious) to what they mean. If you use that metric, it's insanely easy to quantify. Just look at the average refrigerator today, compared to one from the 50s-70s. It's a fraction of the cost, but it's built from cheaper/less reliable parts in a repair-unfriendly (but quick to produce) manner. The idea being that you'll buy a new fridge every 8-12 years and recycle (ideally) the old one, versus spending the cost of a car on one and keeping it for a generation or two. This is what planned obsolescence means, usually. The only nefariously intended to "break" items that I can think of are electronic devices that are unrootable and rely on third-party networked services.

HeyLaughingBoy 3y ago
Oh, I completely agree with you on that. Most consumer items are built to a price point. If you're building to sell at a low price, you have to keep Bill of Materials cost low to make selling the thing worthwhile, so it's not surprising that, e.g., a cheap riding mower is made from thin stamped steel chassis whereas a commercial one is mostly heavy weldments that hold up to being banged around for hours each day. I'm not being difficult. When I read "engineered to fail" that's not the impression I get from the statement.
- derefr 3y ago
  Honestly seems to me that some BOMs (and therefore some practically-achievable price-points) should be illegal, then. You shouldn't be allowed to market something as a mower, if it's built such that the act of mowing gradually shakes the mower apart. Yes, a change like this would mean that, in the short term, there'd suddenly be no "consumer" version of many products. But that'd only be the short term. In the medium term, I'd expect heavy pressure for innovation in materials science, with all these companies that were fine with plastics before, suddenly investing money and labor into operationalization of e.g. scaling carbon-fiber production.
  - ultrarunner 3y ago
    This sounds like me like an inquiry into "quality" and an attempt to make illegal those products lacking a certain quality. I generally call these products "<thing> shaped objects", e.g. a helmet shaped object that has all the outward appearance of an actual helmet, but does little to protect the wearer in the event of a crash. "DOT standards!" you might object, but DOT is generally known to be the worst standard in the world, often holding the industry back instead of moving it forward. If the department of transportation is unable to properly regulate safety equipment like helmets, I'm not sure I expect better results from a government committee intended to regulate the quality of nearly everything. This, of course, assumes that one can not only define "quality", but determine a threshold on a spectrum that delineates legality. Or maybe we'll just accept Tsars that "know it when they see it."
    - derefr 3y ago
      Yes, there is no general definition of "quality." But every industry and product has its own internal, domain-specific definition of quality. For hard drives, "quality" is MTBF. For batteries, "quality" is measured in loss of charge capacity per charge cycle. Or let me put it this way: the commercial/industrial versions of these products do some things differently. Why do they do those things? To increase "quality." If the industry didn't know what its "quality" metric was, then it would be impossible for them to make the commercial/industrial product "better" for long-term commercial/industrial use than the consumer one. In any industry where the commercial/industrial version of a product — one that lasts decades in heavy use — is already an existence proof for the possibility of "quality" in the product category, you can simply regulate that the consumer version must also be made to last at least N years of regular consumer-duty use. Doesn't matter how they accomplish that. Maybe they can't accomplish that, with positive margins, at a price point anyone is willing to buy, at first. Oh well. Keep trying. Compare/contrast: FDA stage-3 drug trials — the trial phase that tests drug efficacy. It's up to the drug's manufacturer to declare to the FDA what effect the drug is supposed to have — it's the very same effect the company is applying to the FDA to be able to market the drug as having. An efficacy trial, is simply the FDA demanding, from a drug's manufacturer, proof positive of its own planned marketing claims about the drug. That efficacy proof uses metrics specific to the pathology that the drug treats — and likely metrics invented by the drug manufacturer themselves, while researching the problem. But crucially, the manufacturer, before even starting the trial, has to convince the FDA that these metrics are sensible ones to measure efficacy by; and also has to work with the FDA to reach a consensus on what would constitute a satisfactory level of efficacy for their drug (i.e. what metrics thresholds are meant by a marketing claim like "relieves headaches.")

nivenhuh 3y ago

Kitchen aid stand mixers converted from using metal gearing to plastic gearing in their consumer stand mixers. After a certain amount of use, the gear wears out and costs $50 for a replacement. The commercial line still uses metal gears. The maintenance on it is to check grease/lubricant after a certain amount of use. (We used the stand mixer daily. Our home edition lasted 6-9 months before needing a gear change. The commercial edition has been going strong for a few years now.) I’m sure there’s a reason why they moved to a fail-safe gear for consumer use — but as a consumer — I have no clue what that reason is. (We do ask a lot of our mixer tho!)

aeyes 3y ago
Does the plastic gear break if you attempt to recreate "will it blend" videos at home? They probably try to sell this as a safety feature.
HeyLaughingBoy 3y ago
I have one of those mixers and I've replaced the sacrificial gear at least 3 times, although I usually get the gears for far less than $50. I gotta learn to not overload it with bread dough :-) Based on what I see when I open up the unit, the reason they don't have an all metal gear train is that doing that would impose the need for higher strength on everything in the transmission and the chassis up to the motor. That would increase the cost to the point where it would cut into sales. The larger consumer mixers (6qt?) are built more heavy duty since I know that they can take a larger vertical load, but I don't know if they also have the nylon gear.
- winrid 3y ago
  They can use glass reinforced plastic instead, and powdered metal or nylon gears like the mid range $150 consumer drills...
  - HeyLaughingBoy 3y ago
    I think I may have misunderstood GP's post. I thought they meant that one of the gears was changed to plastic (as in mine) with the rest remaining metal. But it's more likely that they meant that the newer models are now using a fully plastic geartrain based on what I've read since.

mrguyorama 3y ago

>Sacrificial parts that are designed to fail in order to mitigate a more serious failure do not count for the purposes of this request -- that's just Good Engineering Practice. Except when that part breaks and the company does not make replacements available and the product was not meant to be taken apart to replace it. Mechanical fuses only work when you can easily buy and replace the mechanical fuse and ALSO fix whatever caused the failure in the first place. Otherwise it's just a weak link.

HeyLaughingBoy 3y ago
Yes, but. That designed-in weak link that you can't fix could be the difference between you being pissed off because your machine doesn't work anymore and you losing a hand.
- winrid 3y ago
  That's just not the thought process. A vacuum with a cheap motor isn't going to have trouble hurting your fingers if you stick them in the brush at the right angle. But the bearings will wear out in 5 years. Another is drills with cheap housings or gears. The drill will happily rip a glove off and de-skin you. But it'll still wear out faster than if it had metal gears or a tougher housing. Usually safety is an expense. Extra sensors, very carefully engineered weak links that suddenly break under load. Another counter example to your point is my automated litter box. It has a pinch sensor for safety reasons, which is made of two metal contacts. This sensor is directly above the pee/poop so it corrodes and I have to take out like 20 screws in a machine filled with poop to fix it, like every year. They could just have added a plastic cover and one screw to protect the contacts, but no. Probably the only thing I can think of to support your argument is cars. The front end of a car is plastic and metal designed to absorb energy in an impact. But household stuff...

kortex 3y ago

I owned a treadmill (second-hand, details long forgotten, sorry) which had two long steel rails (running the length of the machine) for the main structure. The brackets which connected the rails on the front side were steel, but the ones on the back of the machine were inexplicably plastic. There were major load paths (cyclical loading from running) going straight through these brackets to the feet. Between the wear and plastic embrittlement, these parts were the first to fail, and the entire rest of the machine was in decent condition (easily years of life left). There was nothing particularly complex about that part, they could have easily used steel brackets. I can't help but feel like it was designed for a specific lifespan.

aubanel 3y ago

The father of a friend worked at a high position at Canon. For a specific enterprise command, the client company wanted printers with a lifetime 20,000 copies instead of the base 10,000. Canon went "no problem, we'll see with our engineers" and actually they only had to remove a small device which was basically a print counter and would artificially block the ink input at approx 10,000 copies. So nothing to do with good engineering, only bad business practices.

winrid 3y ago

Usually by using very cheap bearings which last just past the warranty period and cheaping out on reinforcement in critical areas. The AvE YouTube channel covers lots of this with his BOLTR teardowns.

deelowe 3y ago

> Really? Please give an example. I gave you one already. Newer stihl trimmers removed the grease plug. It's impossible to lubricate the trimmer head and they predictably fail after so may hours. A replacement head costs nearly as much as a new trimmer. The head is the most common part that fails on trimmers.