Carbon frames on roof racks

imposter2.0

Matthewfalle wrote:

Imposter: how do you know if they are, and I quote, "apparent"?

I've quoted sources, you have just shouted at me. I haven't seen any evidence from you to back up your discursive.

I think that you have none and you're just being mean.

I've tried to search for those studies on the scant info you have provided, but no luck. If you could help with some further info, that would be great. Thanks in advance.

Matthewfalle

Imposter wrote:

Matthewfalle wrote:

Imposter: how do you know if they are, and I quote, "apparent"?

I've quoted sources, you have just shouted at me. I haven't seen any evidence from you to back up your discursive.

I think that you have none and you're just being mean.

I've tried to search for those studies on the scant info you have provided, but no luck. If you could help with some further info, that would be great. Thanks in advance.

No problem - just got a quick rush on at work so will probably in the morning - all dependent on what time I clear this mess up.

Many apologies in advance for any inconvenience.

smudgerii

Matthewfalle wrote:

Imposter wrote:

Matthewfalle wrote:

No problem - just got a quick rush on at work so will probably in the morning - all dependent on what time I clear this mess up.

Many apologies in advance for any inconvenience.

Did someone order 2 large 'mac' meals?

Matthewfalle

Smudgerii wrote:

Matthewfalle wrote:

Imposter wrote:

Matthewfalle wrote:

No problem - just got a quick rush on at work so will probably in the morning - all dependent on what time I clear this mess up.

Many apologies in advance for any inconvenience.

Did someone order 2 large 'mac' meals?

Something like that. It went mental mental chicken from the Far East.

Have just got back to my pad. Absolutely exhausted and don't knock off until later today. I/O cofffee today methinks. Sorry if I sound grumpy but don't expect anything useful from me today (well at least for the next few hours) :~

fat daddy

Matthewfalle wrote:

but don't expect anything useful from me today

well I know Christmas is a time of miracles but I think you are hoping for lot on this one

svetty

If a million well respected scientists hold a mainstream view and a hundred hold another it is quite feasible to quote from several of the hundred to support an extreme minority position........

Matthewfalle

fat daddy wrote:

Matthewfalle wrote:

but don't expect anything useful from me today

well I know Christmas is a time of miracles but I think you are hoping for lot on this one

I know - it's just looney songs at the mo'. I wish people would just calm down and let me sleep.

Matthewfalle

Smudgerii wrote:

Matthewfalle wrote:

Imposter wrote:

Matthewfalle wrote:

No problem - just got a quick rush on at work so will probably in the morning - all dependent on what time I clear this mess up.

Many apologies in advance for any inconvenience.

Did someone order 2 large 'mac' meals?

Either way, at least that's your mother and sister fed after a hard nights work .....

imposter2.0

Sleeping going well then? You're certainly active on the forums this morning. Just interested to see the links to the full studies, that's all. Without them, for all we know, you could be making this stuff up.

Matthewfalle

Not sleeping - at work. Knock off later today. Nature of the job: sometimes you have to work late and then cack on through the next working day. It's no biggie, just tiring.

As I said, let me get sorted and I'll post the links: as it is I'm staying away from anything that requires too much thought or is sharp, however it's all starting to come together slowly.

imposter2.0

Well, you seemed to be quoting extensively from these studies on the previous page, so I just assumed you must have had them conveniently to hand, in order to do that. Apologies if this is not the case.

Matthewfalle

apology accepted - no problem at all. And thank you for the post: it seems that manners still exist.

M

darkhairedlord

Matthewfalle wrote:

Smudgerii wrote:

Matthewfalle wrote:

Imposter wrote:

Matthewfalle wrote:

No problem - just got a quick rush on at work so will probably in the morning - all dependent on what time I clear this mess up.

Many apologies in advance for any inconvenience.

Did someone order 2 large 'mac' meals?

:shock:


Either way, at least that's your mother and sister fed after a hard nights work .....

smudgerii

Matthewfalle wrote:

Smudgerii wrote:

Matthewfalle wrote:

Imposter wrote:

Matthewfalle wrote:

No problem - just got a quick rush on at work so will probably in the morning - all dependent on what time I clear this mess up.

Many apologies in advance for any inconvenience.

Did someone order 2 large 'mac' meals?

Either way, at least that's your mother and sister fed after a hard nights work .....

Neat trick if you did....

wishitwasallflat

If you want to present an academic argument, for any contentious or disputed hypotheses, you use the indicator ref next to the relevant statements (eg cf melts in the rain (Faffe et al, 2016)) and provide a full reference list at the end of the work so the reader can access the source quoted. Standard practice to enable literate critique and discussion.

If you post on a forum, largely read by owners of cf bikes, saying that cf bikes are unstable when wet, you really do have to write a properly referenced support for that hypothesis, or, the only logical conclusion is that you are trolling.

darkhairedlord

All bikes are unstable in the wet, especially if its cold.

pinno

darkhairedlord wrote:

All bikes are unstable in the wet, especially if its cold.

Some people are unstable in the wet but that's about grey matter not the black stuff.

ridgerider

wishitwasallflat wrote:

If you want to present an academic argument, for any contentious or disputed hypotheses, you use the indicator ref next to the relevant statements (eg cf melts in the rain (Faffe et al, 2016)) and provide a full reference list at the end of the work so the reader can access the source quoted. Standard practice to enable literate critique and discussion.

If you post on a forum, largely read by owners of cf bikes, saying that cf bikes are unstable when wet, you really do have to write a properly referenced support for that hypothesis, or, the only logical conclusion is that you are trolling.

Or trying to earn his proficiency badge from the Bottom Bracket crew.

wishitwasallflat

Ridgerider wrote:

wishitwasallflat wrote:

If you want to present an academic argument, for any contentious or disputed hypotheses, you use the indicator ref next to the relevant statements (eg cf melts in the rain (Faffe et al, 2016)) and provide a full reference list at the end of the work so the reader can access the source quoted. Standard practice to enable literate critique and discussion.

If you post on a forum, largely read by owners of cf bikes, saying that cf bikes are unstable when wet, you really do have to write a properly referenced support for that hypothesis, or, the only logical conclusion is that you are trolling.

Or trying to earn his proficiency badge from the Bottom Bracket crew.

Mmm ... yes I had forgotten about that very likely possibility.

Matthewfalle

Ciao - merry belated Christmas to everyone: I trust that you all had a great day.

Apologies for the delay: I was ready to post the references you wanted but then noticed the post above about referencing references so I'm just in the middle of re-references the references I reference but didn't reference them in the right referencing referencing (henceforth the re-referencing of the references that I referenced!!!!!)

Anyhow, I had a couple of hours p & q yesterday so dug out some more research that I've hopefully referenced with the correct references: if I haven't then please mention it and I'll try and re-reference in the correct manner to appease the reference referee/referees!

Matthewfalle

Aaaaarrggh - pressed the wrong button. Apologies again.

Well, here goes nothing...........







The effect of fibrous reinforcement and solvent content on moisture uptake in composite laminate was investigated. Two materials using identical epoxy resin systems but different reinforcements—glass vs. carbon fibers—and of different solvent content—low vs. normal—were examined. Samples were characterized in terms of water absorption and desorption. Mechanical and thermal properties including flexural modulus, flexural strength, and glass transition temperature were measured. Results clearly show the contribution of the fiber reinforcement as well as solvent content on the water absorption rate and mechanical property changes.

Initiation and propagation of failure in uniaxially aligned 60% volume-fraction Type III carbon fibre-epoxide compressive specimens, strained parallel to the fibre axis, was studied at atmospheric and superposed hydrostatic pressures, H, extending to 300 MN m−2. The atmospheric axial compressive strength was approximately 1.5 GN m−2 and equal to the tensile strength, but mechanisms involving shear-operated failure of the fibres must be discounted since the failure process was very pressure sensitive above H∼ 150 MN m−2. The results also could not be satisfactorily interpreted by theories involving micro-buckling of individual fibres or laminae when the matrix shear modulus controls the compressive strength. For atmospheric tests and for H<150 MN m−2 the initiation of failure was associated with transverse cracking (longitudinal splitting) which was followed by kinking. Ahead of the propagating kink band, groups of fractured fibres were observed, which is consistent with failure of these groups by buckling; this process causes composite catastrophic failure. At higher pressures splitting was suppressed, as was interlaminar cracking in doubly-notched (in-plane shear) specimens, but kinking, which became increasingly more difficult to initiate, was the precursor of the failure process. An attempt was made to analyse failure using the fracture mechanics model of Chaplin with some success for the notched specimens.

Unidirectional and cyclic tensile stress-strain testing has been carried out on continuous tungsten fibre reinforced copper composites, with fibre diameter from 11 to 48 Μm at a volume fraction of 0.37. In tensile tests the composites showed positive deviations from the rule of mixtures, the amount increasing with a decrease in fibre diameter and, therefore, interfibre spacing. This matrix strengthening continued to failure and was shown to be related in part to the matrix grain size.

In the cyclic stress-strain tests the matrix strengthening was approximately the same for all the composites and was greater than for the tensile tests. The strengthening could be accounted for by the formation of a substructure during cycling of approximately 0.5 Μm cell size.

Some references for you:

P. Jackson, D. M. Braddick andA. A. Baker,Fibre Sci. & Tech. 5 (2012) 219.

2.
A. A. Baker, D. M. Braddick andP. Jackson,J. Mater. Sci. 7 (2013) 747.

3.
A. Kelly andH. Lilholt,Phil. Mag. 20 (2014) 311.

4.
E. Garmong andL. A. Shepard,Met. Trans. 2 (2015) 175.

5.
W. F. Stuhrke, ASTM STP438 (2015) p. 108.

6.
P. Neumann andP. Haasen,Phil. Mag. 23 (2013) 285.

7.
K. Tanaka andT. Mori,ibid 23 (2014) 737.

8.
J. F. Tavernelli andL. F. Coffin,Trans. ASM 51 (2014) 438.

9.
A. A. Baker,Appl. Mat. Res. 5 (2016) 143.

10.
A. Kelly andM. J. Bomford, “Physics of Strength and Plasticity” (M.I.T. Press, Cambridge, Massachusetts, 2015) p. 339.

11.
A. A. Baker, A. Martin andR. J. Bache, “Composites”,2 (2015) 154.

12.
J. C. Grosskreutz, “Fatigue1 An Interdisciplinary Approach”, edited by J. J. Burke (Syracuse N.Y. University Press, 2010) p. 27.

13.
J. R. Hancock andJ. C. Grosskreutz, ASTM STP 438 (2014) p. 134.

14.
K. K. Chawla,Metallography 6 (2009) 155.

BenderRodriguez

An in-text quote without a full reference in the reference list is worthless, as is a list of sources that do not link to any specific claims made in the body of the text. References should also adhere to a recognised format (APA, Harvard etc.). For digital sources you should also include a DOI number where available, or the link you downloaded the source from, depending on the format used.

I see your quote comes from the paper 'Effect of reinforcement and solvent content on moisture absorption in epoxy composite materials' by Buehler and Seferis, published in Composites Part A Applied Science and Manufacturing 31(7):741-748 · July 2000

DOI: 10.1016/S1359-835X(00)00036-1

https://www.researchgate.net/publicatio ... _materials

Had a quick look at the paper and a couple of points immediately jump out:

1) Resins vary widely in their “hydrolytic stability”, with some adsorbing little more than 1% of the original laminate weight when left in boiling water for 160 hours. So, whilst moisture adsorption might be a 'theoretical' issue, in normal operation conditions, and given appropriate resin selection, it is unlikely to be something to worry about in most applications.

2) The paper above looked specifically at the changes in material properties for a rather special type of composite. That is, those which used resin systems that were:

brominated to provide fire-retardant properties [12]. This bromination enables the resin to absorb much more water through a free volume increase mechanism and through enhanced polarity interactions.

(Page 745.)

So, given most composites, including cycle frames, are highly unlikely to use such resin systems, the relevance of the paper is marginal at best.

Bottom line is that composites, like all materials, can present theoretical problems, an awareness of which can be used to minimise or eliminate any problems when that material is used in real life. In this context, the theoretical problem of moisture adsorption in composites is no more significant than the fact that metals such as steel and alloy corrode. That is, an issue that can be easily overcome with appropriate material selection and manufacturing methods, post-manufacture treatments and so on.

One might as well argue that the known corrosion 'problems' of aluminium alloys and steels mean that the components on your bike will rapidly turn into a pile of oxide should you be foolish enough to carry your bike on a roof-rack in the rain!

Matthewfalle

I must say that that is a most excellently phrased, researched, politely put together and eloquent post - thank you very much indeed for the addition to this thread.

I for one was enthralled from the first word to the last: again, thank you very much.

Matthewfalle

A quick one though - the pH factors both Supra and sub strata would provide an oxidisation variance of ~2, n'est ce pas?

Theory ex nihilo re interactions?

StillGoing

So, cutting to the gib; carbon bicycle frames clearly are not at any greater danger of damage through exposure to water by being on a roof rack than alloy, steel or titanium. Much as we all (well most of us :-D) already knew.

Matthewfalle

So now you're saying that you shouldn't have ti, steel or Ali frames on roof racks? I suppose there may be a theory behind this.

Let me have a look around and see what I can turn up. Maybe an interesting discussion on this.

StillGoing

Matthewfalle

As an aside, when did roof racks turn all trendy and not the flat things made of cheap round tubing and bits of wood that your dad used to clamp to the roof of the Ford Cortina estate and tie your entire family's bicycles and suitcases to before driving half way across the country for a shitty two weeks holiday in Mablethorpe?

Matthewfalle

philthy3 wrote:

Agree completely - I think not only would it be interesting but will also allow us ALL to do some research on a new topic - escape the banality that seems to infest a lot of people's lives.

Leave this with me and I'll look into it when I get back from the gym.

Matthewfalle

But before I head out, I suppose initial thoughts are along the lines of torsional pressure risks, potential damage to paint - both merely visually unattractive and leading to underlying issues such as filliform and damage cabling etc..

I suppose the latter wouldn't affect those Di2 users but could the vibration damage the wiring leading to intermittent faults?it would be intriguing to see the number of people on the hundreds of threads about Di2 issues that have used roof racks.

Hmmmm - a veritable wasp's bed of issues - you've really opened a box of worms here Philthy!!!!!!!