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Carbon Bikes and Quality Control



 
 
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  #11  
Old May 30th 17, 03:16 PM posted to rec.bicycles.tech
JBeattie
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Posts: 5,870
Default Carbon Bikes and Quality Control

On Monday, May 29, 2017 at 6:58:01 PM UTC-7, John B. wrote:
On Mon, 29 May 2017 15:54:30 -0700 (PDT), jbeattie
wrote:

On Monday, May 29, 2017 at 8:40:18 AM UTC-7, wrote:
Quality control for metal bikes is relatively easy - especially for steel since all of the important connection can be seen on the workmanship.

But carbon fiber bikes are another matter. No matter how well the factory is trying to make no errors these can be made. And once made they are almost invisible.

John seems to want to argue that you can get crystal clear epoxies with viscosities down to 200 when my source says that they are limited to 1200 to 1600. This makes little difference since these particular epoxies are usually only used on the surface layer of the frames for purely decorative effect.

But those are the last layers laid on the inflatable bladder that is used for the inside mold of a one piece frame or fork.

The inside layers are the sources of danger. High end bikes use many very thin layers and the lay-up is completed as rapidly as possible. A bubble can be caught or a section of cloth may not be properly wetted. This makes an area where movement between the layers can begin and this can break down the surrounding resins.

Now my experience has shown me that CF is not reliable. But companies whose engineers I respect and my own research have shown that carbon fiber without any errors in construction can be much stronger and lighter than steel and have as long if not longer life.

So what we need is more information on the percentages of CF bikes that are having quality control problems.

And you can bet that the companies that make these bikes are going to remain tight lipped on this even if only one bike in a thousand have quality issues.

Question - are the pro level bikes that are breaking so often custom built in their company's racing labs so that the quality control is much lower than the assembly lines in China or Taiwan? If so with increasing familiarity with the material we can expect the racing teams to have progressively less trouble with their mounts.

Once constructed there is almost no way of detecting fatal flaws in the construction and that is a bonus for the American legal system in which a broken fingernail can end in a million dollar settlement.

So until we have tort reform we have little way of knowing just how safe a carbon fiber frame and fork are.

So you make your choice and you take your chances. And please don't hire a lawyer the day you buy a new super-light bike.


I don't get your point about the American legal system, tort reform and knowing whether CFRP frames/forks are safe. People break forks and sue. I've defended those cases. Failures are also reported to the CPSC and may result in a recall. Go to the CPSC website and search for "bicycle fork." There is also a CPSC requirement for fork strength, but it's pretty minimal. ISO/CEN/ASTM have more rigorous standards. Again, this does not mean every fork that comes off the line is flawless.

-- Jay Beattie.


Would you care to comment whether, based on the court cases you are
failure with and the C.F. bicycles you are aware of, C.F. bike
breakage, disregarding severe crashes which would likely damage a
metal frame, appear to be a significant problem?


A while ago, I did a verdict/settlement search on LEXIS -- which is a poor data base because it relies on voluntary reporting. There were a handful -- maybe five -- carbon fork cases. One of the largest verdicts (against Trek) was taken reversed by the court of appeals. http://caselaw.findlaw.com/fl-distri...l/1694841.html

Many attorneys (including me) don't report, so its impossible to get an accurate number. ISO (Insurance Services Office) keeps a claims data base, but I think it is by claimant and not product or cause. Many failures never get beyond the warranty replacement phase.

None of these resources is very good at weeding out the true product failures from the Miguelez situation where something got caught in the wheel or the rider crash causing the failure. I had a case where a dog leash got caught in the front wheels and snapped the CF forks. The manufacturer settled for a tiny sum to make the case go away. I had one where there was a manufacturing defect (bond failure), and the manufacturer paid a reasonable sum. I tried a shock fork case to a defense verdict, but that was aluminum. I had a bunch of aluminum shock fork cases, all of the failures due to the same design defect. That's the deal -- if there is a massive design or manufacturing defect, then you see bunches of these cases. Even if my bicycle manufacturer clients chose to send the work to another attorney, I'd still see the filings in the courthouse news. I would not see the claims being handled in-house by risk management, but I would hear about the recall. Reputable manufacturers are pretty quick to recall.

So like I said, I'm not seeing an epidemic -- but that doesn't mean one-off failures don't occur or that there are not failures resulting in warranty replacement claims. Every bike part has a failure rate.

-- Jay Beattie.


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  #12  
Old May 30th 17, 06:08 PM posted to rec.bicycles.tech
Jeff Liebermann
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Posts: 4,018
Default Carbon Bikes and Quality Control

On Tue, 30 May 2017 07:10:00 -0700 (PDT), wrote:

Jeff - on the Apple assembly line they were actually whipping
workers to work faster. Do you really think that that attitude
is somehow less prevalent with bicycle manufacturers?


"The beatings will continue until morale improves"
Captain Bligh in the Mutiny on the Bounty.

I would bet that one out of ten bikes are quality tested with
ultrasound or vibrational testing which I would have little
faith in since the lay-ups are so thin that if the problem
isn't obvious you would be hard pressed to detect it with
vibration.

Remember that the inside and outside coats are probably fine.
A small bubble couldn't be detected by either method.


End to end vibration and resonance testing is a QA test performed on a
finished frame. These do not show the location of a flaw. They
merely detects that a frame is structurally different from a known
good sample and that it should be inspected further. They're useless
for detecting small bubbles but will detect most every other type of
construction and assembly defect.

Ultrasonic inspection comes in various flavors (reflection, pass
through, axial, diffraction, etc).
http://www.olympus-ims.com/en/ut-flaw/
You would not find these on the production line as they require an
expert to operate and analyze the output.
http://www.olympus-ims.com/en/omniscan-mx2/
They're commonly used for composite inspection:
http://www.qualitymag.com/articles/92050-ultrasonic-testing-of-fiberglass-and-carbon-fiber-composites
The 3rd photo from the left clearly shows the voids in the hull.

Some of the schemes and devices used in aircraft laminate inspection:
http://www.olympus-ims.com/en/applications/non-destructive-bond-testing-aircraft-composites/

There are also simple testers designed specifically for composite and
laminate inspection:
http://www.olympus-ims.com/en/ultrasonic-precision-thickness-gages/35rdc/
I would expect to find plenty of these in the factory.

There's also radiographic (xray) and radioactive inspection equipment,
which I would not expect to see on a production line.

I don't know if any of this is actually performed. My guess(tm) is
that they do an overall vibration test to look for gross errors. If
something is found, they simply trash the frame because it's cheaper
to do so than to perform difficult corrective repairs and patch work
on a built up frame. You might be correct that they ignore bubbles.
Dunno.

It would be interesting to rent or borrow one of these ultrasonic
inspection instruments, and run through the inventory at an LBS (local
bike shop). If your suspicions and allegations are correct, it should
identify some defects.


--
Jeff Liebermann

150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #13  
Old May 30th 17, 06:32 PM posted to rec.bicycles.tech
JBeattie
external usenet poster
 
Posts: 5,870
Default Carbon Bikes and Quality Control

On Tuesday, May 30, 2017 at 10:08:22 AM UTC-7, Jeff Liebermann wrote:
On Tue, 30 May 2017 07:10:00 -0700 (PDT), wrote:

Jeff - on the Apple assembly line they were actually whipping
workers to work faster. Do you really think that that attitude
is somehow less prevalent with bicycle manufacturers?


"The beatings will continue until morale improves"
Captain Bligh in the Mutiny on the Bounty.

I would bet that one out of ten bikes are quality tested with
ultrasound or vibrational testing which I would have little
faith in since the lay-ups are so thin that if the problem
isn't obvious you would be hard pressed to detect it with
vibration.

Remember that the inside and outside coats are probably fine.
A small bubble couldn't be detected by either method.


End to end vibration and resonance testing is a QA test performed on a
finished frame. These do not show the location of a flaw. They
merely detects that a frame is structurally different from a known
good sample and that it should be inspected further. They're useless
for detecting small bubbles but will detect most every other type of
construction and assembly defect.

Ultrasonic inspection comes in various flavors (reflection, pass
through, axial, diffraction, etc).
http://www.olympus-ims.com/en/ut-flaw/
You would not find these on the production line as they require an
expert to operate and analyze the output.
http://www.olympus-ims.com/en/omniscan-mx2/
They're commonly used for composite inspection:
http://www.qualitymag.com/articles/92050-ultrasonic-testing-of-fiberglass-and-carbon-fiber-composites
The 3rd photo from the left clearly shows the voids in the hull.

Some of the schemes and devices used in aircraft laminate inspection:
http://www.olympus-ims.com/en/applications/non-destructive-bond-testing-aircraft-composites/

There are also simple testers designed specifically for composite and
laminate inspection:
http://www.olympus-ims.com/en/ultrasonic-precision-thickness-gages/35rdc/
I would expect to find plenty of these in the factory.

There's also radiographic (xray) and radioactive inspection equipment,
which I would not expect to see on a production line.

I don't know if any of this is actually performed. My guess(tm) is
that they do an overall vibration test to look for gross errors. If
something is found, they simply trash the frame because it's cheaper
to do so than to perform difficult corrective repairs and patch work
on a built up frame. You might be correct that they ignore bubbles.
Dunno.

It would be interesting to rent or borrow one of these ultrasonic
inspection instruments, and run through the inventory at an LBS (local
bike shop). If your suspicions and allegations are correct, it should
identify some defects.


Our local CF inspection and repair outfit:
http://www.ruckuscomp.com/process Scroll down on the page (graphic restoration). Note to Tom: stop buying Colnagos.

-- Jay Beattie.
  #14  
Old May 30th 17, 07:20 PM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 3,345
Default Carbon Bikes and Quality Control

On Tuesday, May 30, 2017 at 10:32:10 AM UTC-7, jbeattie wrote:
Note to Tom: stop buying Colnagos.


So most of those repairs are to other bikes but Colnago is more dangerous?

Most of the other bikes are breaking under 150 lb riders that do 1,000 miles a year but a Colnago breaking under a 190 lb rider that does 6,000 miles a year is taking a more dangerous chance?
  #15  
Old May 30th 17, 09:19 PM posted to rec.bicycles.tech
JBeattie
external usenet poster
 
Posts: 5,870
Default Carbon Bikes and Quality Control

On Tuesday, May 30, 2017 at 11:20:29 AM UTC-7, wrote:
On Tuesday, May 30, 2017 at 10:32:10 AM UTC-7, jbeattie wrote:
Note to Tom: stop buying Colnagos.


So most of those repairs are to other bikes but Colnago is more dangerous?

Most of the other bikes are breaking under 150 lb riders that do 1,000 miles a year but a Colnago breaking under a 190 lb rider that does 6,000 miles a year is taking a more dangerous chance?


I know of no one who has broken as many CF forks of the same brand as you. You even have friends who broke Colnagos.

I broke a bunch of Cannondale aluminum frames, but they didn't drop me on my face. They had frame cracks and no fork failures. I weigh more than you and ride more miles annually (although on several different bikes) and have never broken a fork. Not saying I won't, but if I were breaking Cannondale forks (for example), I'd buy Trek or Specialized -- and a better health plan.

-- Jay Beattie.

  #16  
Old May 30th 17, 11:19 PM posted to rec.bicycles.tech
Jeff Liebermann
external usenet poster
 
Posts: 4,018
Default Carbon Bikes and Quality Control

On Tue, 30 May 2017 10:32:08 -0700 (PDT), jbeattie
wrote:

On Tuesday, May 30, 2017 at 10:08:22 AM UTC-7, Jeff Liebermann wrote:
I don't know if any of this is actually performed. My guess(tm) is
that they do an overall vibration test to look for gross errors. If
something is found, they simply trash the frame because it's cheaper
to do so than to perform difficult corrective repairs and patch work
on a built up frame.


Our local CF inspection and repair outfit: http://www.ruckuscomp.com/process
Scroll down on the page (graphic restoration). Note to Tom: stop buying Colnagos.
-- Jay Beattie.


Such repair shops are great for fixing damage to an individual
bicycle, which can be an economical alternative to buying a new frame
($300 to maybe $2,000). However, for a factory production line in
China, the cost of repair would far exceed the cost to manufacture for
the frame. That's only the frame because the bicycle hasn't been
loaded with attachments, accouterments, and bolt-ons quite yet. That
makes the frame somewhat cheap, making it more economical to throw it
out instead of repair it.

It would be interesting to rent or borrow one of these ultrasonic
inspection instruments, and run through the inventory at an LBS (local
bike shop). If your suspicions and allegations are correct, it should
identify some defects.


If you have time, give the Ruckus Composites people a visit or call.
Ask if they have any ultrasonic inspection equipment, which model, how
it's used, etc.

--
Jeff Liebermann
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
  #17  
Old May 31st 17, 12:58 AM posted to rec.bicycles.tech
[email protected]
external usenet poster
 
Posts: 3,345
Default Carbon Bikes and Quality Control

On Tuesday, May 30, 2017 at 1:19:49 PM UTC-7, jbeattie wrote:
On Tuesday, May 30, 2017 at 11:20:29 AM UTC-7, wrote:
On Tuesday, May 30, 2017 at 10:32:10 AM UTC-7, jbeattie wrote:
Note to Tom: stop buying Colnagos.


So most of those repairs are to other bikes but Colnago is more dangerous?

Most of the other bikes are breaking under 150 lb riders that do 1,000 miles a year but a Colnago breaking under a 190 lb rider that does 6,000 miles a year is taking a more dangerous chance?


I know of no one who has broken as many CF forks of the same brand as you.. You even have friends who broke Colnagos.

I broke a bunch of Cannondale aluminum frames, but they didn't drop me on my face. They had frame cracks and no fork failures. I weigh more than you and ride more miles annually (although on several different bikes) and have never broken a fork. Not saying I won't, but if I were breaking Cannondale forks (for example), I'd buy Trek or Specialized -- and a better health plan.


That's strange because I only broke one Colnago fork. The others were Look and IRD. And it was the IRD that dropped me on my face. So you count one as "more than anyone"?

https://www.google.com/search?q=Brok...bUCkWlel17MJM:

"Cannondale - doesn't offer a Limited Lifetime Warranty because their bikes fail (crack as you put it) on a regular basis."

" was commuting to work on my carbon fiber cannondale synapse. I had just climbed a very short hill, coasted for a bit, and on my next pedal stroke by bike came to an immediate and abrupt complete stope. Fortunately, I was only going about 8mph and was able to click out of the pedals without crashing. Upon inspection, my rear derailluer was firmly jammed into the rear wheel and spokes as well as into the rear cassette. I thought the derailleur hanger had broken.

I took the bike to the shop where I purchased the bike (Old Town Bikes, Olympia, WA.) They were able to pry the rear wheel away and get the derailluer out of the spokes. Upon their inspection, the dearailleur hanger had not broken but had torn through the carbon fiber rear dropouts. The result... carbon fiber frame us now useless. The bike shop submitted a claim to Cannondale. Cannondale came back with their decision today and said they would offer me 20 percent off for crash replacement. I explained, there was no crash where the bike was damaged. Plus, nearly all bikes are reduced 20 percent off for the new models coming in... their "offer" was really no offer at all."

"I was washing my bike the other day and noticed a crack under the crown of the fork of my supersix, opposite where the tire spins. I have no idea how this could have happened, as I didn't crash"

https://www.youtube.com/watch?v=prdqBNPhMFk

Yeah, you're safe as hell on a Cannondale because you haven't been hurt yet..

  #19  
Old May 31st 17, 02:09 AM posted to rec.bicycles.tech
John B.[_3_]
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Posts: 5,697
Default Carbon Bikes and Quality Control

On Tue, 30 May 2017 07:16:00 -0700 (PDT), jbeattie
wrote:

On Monday, May 29, 2017 at 6:58:01 PM UTC-7, John B. wrote:
On Mon, 29 May 2017 15:54:30 -0700 (PDT), jbeattie
wrote:

On Monday, May 29, 2017 at 8:40:18 AM UTC-7, wrote:
Quality control for metal bikes is relatively easy - especially for steel since all of the important connection can be seen on the workmanship.

But carbon fiber bikes are another matter. No matter how well the factory is trying to make no errors these can be made. And once made they are almost invisible.

John seems to want to argue that you can get crystal clear epoxies with viscosities down to 200 when my source says that they are limited to 1200 to 1600. This makes little difference since these particular epoxies are usually only used on the surface layer of the frames for purely decorative effect.

But those are the last layers laid on the inflatable bladder that is used for the inside mold of a one piece frame or fork.

The inside layers are the sources of danger. High end bikes use many very thin layers and the lay-up is completed as rapidly as possible. A bubble can be caught or a section of cloth may not be properly wetted. This makes an area where movement between the layers can begin and this can break down the surrounding resins.

Now my experience has shown me that CF is not reliable. But companies whose engineers I respect and my own research have shown that carbon fiber without any errors in construction can be much stronger and lighter than steel and have as long if not longer life.

So what we need is more information on the percentages of CF bikes that are having quality control problems.

And you can bet that the companies that make these bikes are going to remain tight lipped on this even if only one bike in a thousand have quality issues.

Question - are the pro level bikes that are breaking so often custom built in their company's racing labs so that the quality control is much lower than the assembly lines in China or Taiwan? If so with increasing familiarity with the material we can expect the racing teams to have progressively less trouble with their mounts.

Once constructed there is almost no way of detecting fatal flaws in the construction and that is a bonus for the American legal system in which a broken fingernail can end in a million dollar settlement.

So until we have tort reform we have little way of knowing just how safe a carbon fiber frame and fork are.

So you make your choice and you take your chances. And please don't hire a lawyer the day you buy a new super-light bike.

I don't get your point about the American legal system, tort reform and knowing whether CFRP frames/forks are safe. People break forks and sue. I've defended those cases. Failures are also reported to the CPSC and may result in a recall. Go to the CPSC website and search for "bicycle fork." There is also a CPSC requirement for fork strength, but it's pretty minimal. ISO/CEN/ASTM have more rigorous standards. Again, this does not mean every fork that comes off the line is flawless.

-- Jay Beattie.


Would you care to comment whether, based on the court cases you are
failure with and the C.F. bicycles you are aware of, C.F. bike
breakage, disregarding severe crashes which would likely damage a
metal frame, appear to be a significant problem?


A while ago, I did a verdict/settlement search on LEXIS -- which is a poor data base because it relies on voluntary reporting. There were a handful -- maybe five -- carbon fork cases. One of the largest verdicts (against Trek) was taken reversed by the court of appeals. http://caselaw.findlaw.com/fl-distri...l/1694841.html

Many attorneys (including me) don't report, so its impossible to get an accurate number. ISO (Insurance Services Office) keeps a claims data base, but I think it is by claimant and not product or cause. Many failures never get beyond the warranty replacement phase.

None of these resources is very good at weeding out the true product failures from the Miguelez situation where something got caught in the wheel or the rider crash causing the failure. I had a case where a dog leash got caught in the front wheels and snapped the CF forks. The manufacturer settled for a tiny sum to make the case go away. I had one where there was a manufacturing defect (bond failure), and the manufacturer paid a reasonable sum. I tried a shock fork case to a defense verdict, but that was aluminum. I had a bunch of aluminum shock fork cases, all of the failures due to the same design defect. That's the deal -- if there is a massive design or manufacturing defect, then you see bunches of these cases. Even if my bicycle manufacturer clients chose to send the work to another attorney, I'd still see the filings in the courthouse news. I would not see the claims being handled in-house by risk management, but I would hear about the recall. Reputable manufacturers are
pretty quick to recall.

So like I said, I'm not seeing an epidemic -- but that doesn't mean one-off failures don't occur or that there are not failures resulting in warranty replacement claims. Every bike part has a failure rate.

-- Jay Beattie.


Interesting. Given that I can't even find any reliable figures for
numbers of cyclists that ride on a regular basis your figures are
probably as accurate as anything else regarding bicycles :-)

--
Cheers,

John B.

  #20  
Old May 31st 17, 02:10 AM posted to rec.bicycles.tech
AMuzi
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Posts: 13,447
Default Carbon Bikes and Quality Control

On 5/30/2017 6:58 PM, wrote:
On Tuesday, May 30, 2017 at 1:19:49 PM UTC-7, jbeattie wrote:
On Tuesday, May 30, 2017 at 11:20:29 AM UTC-7, wrote:
On Tuesday, May 30, 2017 at 10:32:10 AM UTC-7, jbeattie wrote:
Note to Tom: stop buying Colnagos.

So most of those repairs are to other bikes but Colnago is more dangerous?

Most of the other bikes are breaking under 150 lb riders that do 1,000 miles a year but a Colnago breaking under a 190 lb rider that does 6,000 miles a year is taking a more dangerous chance?


I know of no one who has broken as many CF forks of the same brand as you. You even have friends who broke Colnagos.

I broke a bunch of Cannondale aluminum frames, but they didn't drop me on my face. They had frame cracks and no fork failures. I weigh more than you and ride more miles annually (although on several different bikes) and have never broken a fork. Not saying I won't, but if I were breaking Cannondale forks (for example), I'd buy Trek or Specialized -- and a better health plan.


That's strange because I only broke one Colnago fork. The others were Look and IRD. And it was the IRD that dropped me on my face. So you count one as "more than anyone"?

https://www.google.com/search?q=Brok...bUCkWlel17MJM:

"Cannondale - doesn't offer a Limited Lifetime Warranty because their bikes fail (crack as you put it) on a regular basis."

" was commuting to work on my carbon fiber cannondale synapse. I had just climbed a very short hill, coasted for a bit, and on my next pedal stroke by bike came to an immediate and abrupt complete stope. Fortunately, I was only going about 8mph and was able to click out of the pedals without crashing. Upon inspection, my rear derailluer was firmly jammed into the rear wheel and spokes as well as into the rear cassette. I thought the derailleur hanger had broken.

I took the bike to the shop where I purchased the bike (Old Town Bikes, Olympia, WA.) They were able to pry the rear wheel away and get the derailluer out of the spokes. Upon their inspection, the dearailleur hanger had not broken but had torn through the carbon fiber rear dropouts. The result... carbon fiber frame us now useless. The bike shop submitted a claim to Cannondale. Cannondale came back with their decision today and said they would offer me 20 percent off for crash replacement. I explained, there was no crash where the bike was damaged. Plus, nearly all bikes are reduced 20 percent off for the new models coming in... their "offer" was really no offer at all."

"I was washing my bike the other day and noticed a crack under the crown of the fork of my supersix, opposite where the tire spins. I have no idea how this could have happened, as I didn't crash"

https://www.youtube.com/watch?v=prdqBNPhMFk

Yeah, you're safe as hell on a Cannondale because you haven't been hurt yet.


I disagree about one of those examples.

A gear changer in the spokes is not a frame defect. It's an
installation/adjustment/abuse error, far outside the frame
maker's responsibility.

It _may_ be the shop's error, then again it may not be.
That's commonly normal user abuse, such as throwing the bike
gear-down in the back of a pickup or some such. One might
argue (without conclusion usually) between mechanic setup
and user error but it's not the frame maker's problem at any
rate.

--
Andrew Muzi
www.yellowjersey.org/
Open every day since 1 April, 1971


 




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