To what extent do I worry about Carbon Frame damage ?

rickeverett

I was installing some new look pedals today and whilst removing my (rather tight) Shimanos my pedal wrench flew off and hit half way up the right-hand seat stay. (WHY out of all the things does it hit the bike?)

It made a right bang and took two 2mm holes of paint off bout a inch apart in the process.


This is my first ever carbon bike - aluminium and steel were my previous so naturally im worried after hearing talk of "never hit the frame" or "never ride again after X Y Z " !.

I have examined the area best I can, tapping and looking for fractures - I went on a short sprint to see if it would manipulate anything and apart fom the missing paint - nothing.


Do I get worried ? Do I bother with the expense of X-Rays etc ? - Is it REALLY that bad or am I going OTT?

dnwhite88

Touch up the paint with nail polish and forget about it

rickeverett

dnwhite88 wrote:

Touch up the paint with nail polish and forget about it

thanks.

At what point would you worry ? - a crash or big big hit.

This was quite a force with a metal object - (a flying force)

dnwhite88

It sounds like you have just knocked the paint off rather than damaged the carbon underneath-is there carbon showing where the wrench hit? You don't want water getting to the bare carbon because it can cause delamination which is a problem which is why you cover it with nail polish

Of course that is my opinion of what I would (and have) done if it was my bike, if you are worried or through use you get cracks appearing, take it to somebody who knows what they're doing.

rickeverett

dnwhite88 wrote:

It sounds like you have just knocked the paint off rather than damaged the carbon underneath-is there carbon showing where the wrench hit? You don't want water getting to the bare carbon because it can cause delamination which is a problem which is why you cover it with nail polish

Of course that is my opinion of what I would (and have) done if it was my bike, if you are worried or through use you get cracks appearing, take it to somebody who knows what they're doing.

yes its through to the outside of the carbon by the looks of it - no fibres etc exposed just a dark grey/chalky look.

I will follow your suggestion and keep a close eye on it then.

Yossie

They build aeroplanes and tanks and stuff out of carbon,. A pedal wrench isn't going to do anything to it.

Its fine in the dry, just don't ride it in the wet as it'll weft (opposite of warp - directional stuff, generally associated with carbon racing yachts but will relate to pushies as the theories are the same).

If it does get wet, hot air gun/hairdryer lightly all over the frame and it'll be fine (if you hadn't of clonked it you wouldn't need to do this all the time, just when it got really, really wet as water comes up through the cable holes into where it isn't lacquered internally and wefts from the inside (part of the reason why pro mechanics compressor dry all bikes after cleaning)

keef66

Google for some video clips of various people beating seven shades of $hit out of carbon vs alu frames. You'll feel a lot happier.

patrickf

Sounds like you're probably fine. Carbon isn't quite as fragile as people think:

http://www.youtube.com/watch?v=-lsDXEEUlRE

pliptrot

Some time ago I stripped a thread on some carbon bar-ends, so I used a hammer to investigate how tough this stuff is. The answer is, extremely hard, extremely tough and you will have not affected the carbon at all, unless the impact was sufficient to dent a steel tube. And even then.......

chris_bass

Yossie wrote:

They build aeroplanes and tanks and stuff out of carbon,. A pedal wrench isn't going to do anything to it.

Its fine in the dry, just don't ride it in the wet as it'll weft (opposite of warp - directional stuff, generally associated with carbon racing yachts but will relate to pushies as the theories are the same).

If it does get wet, hot air gun/hairdryer lightly all over the frame and it'll be fine (if you hadn't of clonked it you wouldn't need to do this all the time, just when it got really, really wet as water comes up through the cable holes into where it isn't lacquered internally and wefts from the inside (part of the reason why pro mechanics compressor dry all bikes after cleaning)

seriously?! carbon is fine in the wet!! i ride mine in the rain all the time and as yet it hasnt weft (that has to be a made up word?! surely the opposite of warping is not warping which can only be a good thing!) or warped or melted or turned to dust or magically disappeared!

dnwhite88

I ride mine in the wet too and it is yet to 'weft' (I hope that is a word because it's awesome) but the point I was making to the OP was he has exposed the bare carbon which needs sealing as from what I understand water getting to that can damage the lay up. The heat gun sounds a little OTT IMO, the lacquer will keep the elements out fine

slowbike

Oh no - Carbon disintegrates in the wet ...

That's why, on my previous boat, I had to replace the carbon bowsprit after every race, the carbon tiller extension after two races and the carbon mast every 5 races.

Monty Dog

That's why Boeing are having to ground the Dreamliner - not because of the electrical faults, but because you can't fly a carbon plane in the rain! They are developing hydrophobic coatings for this reason ;-)

Youtube Cannondale Taurine or Niner Fork vs hammer an satisfy yourself that you're unlikely to have inflicted any structural damage to your frame.

Burt25

Well I went out on my carbon bike yesterday in the rain and 30 minutes into the ride I noticed it had started to melt. Be warned folks!

Yossie

Slowbike wrote:

Oh no - Carbon disintegrates in the wet ...

That's why, on my previous boat, I had to replace the carbon bowsprit after every race, the carbon tiller extension after two races and the carbon mast every 5 races.

See what I mean? Blimey that must have been expensive and a hassle - and that's for something designed to go in the water as well, never mind a bicycle that's designed to be ridden on dry land in the dry.......

'Fraid its all about form over function lads - they didn't warn you this when you all went out and bought them did they?

Weft is shyt as well as its very, very subtle and you don't notice it until its shot - therefore hot air gun/hairdryer. Ask any decent team mechanic and you'll find out why they spend bloody hours with compressors and countless frames after each race/stage.

Its a real hassle on cheap Chinese (ie Ribble, those all black ones everyone has nowadays, Planet X, etc) as its mono-directional pre-preg these use (unless the more expensive Cippolini, Trek, etc, etc) that are bi-directional lay up - the mono-directional suffers from weft more easily because the fibres are shorter and distort and the pre-preg is more brittle than the wet lay up that the more expensive frames use. That's why they are so cheap.

And I presume that you all used carbon paste and torque wrenches when building up the bikes as well?

The Boeing thing is actually correct to a certain extent - do a Google on it - the Typhoon fighter also suffered from it at the beginning which is why there was such a long delay in it being released.

keef66

Enough of the weft anecdotes already! There's people out there who might take it seriously!

adamfo

The Boeing 777 has been flying with all-composite carbon tail section for some 17 years now.

Yossie

keef66 wrote:

Enough of the weft anecdotes already! There's people out there who might take it seriously!

It is serious - it could kill you.

Yossie

adamfo wrote:

The Boeing 777 has been flying with all-composite carbon tail section for some 17 years now.

Yup - and Google the hassle they had with that and that a multi million (if not billion) dollar aircraft research and building set up, not some dude and his mates in Chong Shin province knocking out bicycle frames to some greedy Westerners who want what the pros have but are too tight to pay for it.

Oh well, its your face/teeth/self respect not mine........... I'm sticking to my 6.5kg ali framed carbon everything else bicycle.

slowbike

Yossie wrote:

carbon everything else bicycle.

You've got Carbon brake cables? Cool

philxx1975

Yossie wrote:

adamfo wrote:

The Boeing 777 has been flying with all-composite carbon tail section for some 17 years now.

Yup - and Google the hassle they had with that and that a multi million (if not billion) dollar aircraft research and building set up, not some dude and his mates in Chong Shin province knocking out bicycle frames to some greedy Westerners who want what the pros have but are too tight to pay for it.

Oh well, its your face/teeth/self respect not mine........... I'm sticking to my 6.5kg ali framed carbon everything else bicycle.

Did you per chance work in this advanced Boeing Research centre?

smoggysteve

Yossie wrote:

They build aeroplanes and tanks and stuff out of carbon,.

Not sure I would feel safe in a Carbon Fiber tank. Considering a 1cm thick steel plate cannot always stop a 7.62mm round, what the hell is carbon going to do???? :-)

Yossie

SmoggySteve wrote:

Yossie wrote:

They build aeroplanes and tanks and stuff out of carbon,.

Not sure I would feel safe in a Carbon Fiber tank. Considering a 1cm thick steel plate cannot always stop a 7.62mm round, what the hell is carbon going to do???? :-)

As Steve well knows, the armour and schizzle on the outside is all Kevlar and associated nowadays - a load of the insides and all the whizzy computer stuff that fires the gun (is that the correct term? I'm maroon, not smelly tank so not really sure) is all housed and secured in carbon.

As an aside, I went on a new lifeboat (Taymour class) the other day as part of a chopper med thingie I'm doing: its all carbon and really freakin' cool: its like the spaceship that the rock band own that gets fired into the sum at the end of each meal from Milliways.

Yossie

philxx1975 wrote:

Yossie wrote:

adamfo wrote:

The Boeing 777 has been flying with all-composite carbon tail section for some 17 years now.

Yup - and Google the hassle they had with that and that a multi million (if not billion) dollar aircraft research and building set up, not some dude and his mates in Chong Shin province knocking out bicycle frames to some greedy Westerners who want what the pros have but are too tight to pay for it.

Oh well, its your face/teeth/self respect not mine........... I'm sticking to my 6.5kg ali framed carbon everything else bicycle.

Did you per chance work in this advanced Boeing Research centre?

No, but when you do my job you have loads of spare time on occasions and debates do go on. We like to mock the boys in blue so need sufficient ammunition at all times - one lad was ex Boeing test pilot so we used to mock him that all their stuff fell out of the air because he helped design a rubbish bit that melted when it got wet and that it was all his fault.

Well funny until he dropped a load of stuff on us out of retaliation.......

Yossie

Slowbike wrote:

Yossie wrote:

carbon everything else bicycle.

You've got Carbon brake cables? Cool

Cheers dude - well light as well. Black (obviously) so 2mph faster than normal brake cables as well.

Thinking about it, carbon brake cables may actually work - long strands of pre preg .... hmmm, we may have something here. Its only the inherent elasticity of metal as opposed to dense non - elasticity of carbon strands that may cause it to not work .......

smoggysteve

Yossie wrote:

SmoggySteve wrote:

Yossie wrote:

They build aeroplanes and tanks and stuff out of carbon,.

Not sure I would feel safe in a Carbon Fiber tank. Considering a 1cm thick steel plate cannot always stop a 7.62mm round, what the hell is carbon going to do???? :-)

As Steve well knows, the armour and schizzle on the outside is all Kevlar and associated nowadays -

Kevlar? On a tank. Are you sure? Only piece of eqpt I have used made of kevelar is my helmet, or Ospray plates. and I still wouldnt trust that to take a large round as they crack when impacted.(trust me , I have seen it first hand) If CF is used inside its more likely its a wight saving thing than anything else.

markos1963

OP don't listen to all this tripe about water affecting carbon, it's all a myth. What they haven't told you is that carbon bikes left in sheds are at danger due to spider webs. Apparently some chemical in the silk dissolves the resins in the carbon and causes delamination at speeds over 30mph. Be careful out there.

Yossie

Agree - weight saving but they only use it inside. Yup - its all Kevlar stuff nowadays - steel isn't real I'm afraid. Its just heavy and shyt.

Its all about kinetic energy penetration - steel has average stopping power offset by ludicrous weight but cannot dissipate the energy of the round, Kevlar and Chobham can - its why you don't get steel helmets anymore.

Yossie

markos1963 wrote:

OP don't listen to all this tripe about water affecting carbon, it's all a myth. What they haven't told you is that carbon bikes left in sheds are at danger due to spider webs. Apparently some chemical in the silk dissolves the resins in the carbon and causes delamination at speeds over 30mph. Be careful out there.

Fukk me. Now even the spiders hate us.

No wonder Ziggy wasn't a cyclist ..................

desweller

Yossie - don't forget that aircraft have enormous air pressures to deal with as well. Their environments are far more demanding when it comes to penetration of the composite matrix. The same problems with boats; they are continually exposed to seawater, so if there is a flaw in the composite then it will be found.

No bicycle sees high damp air pressures or is submerged (apart from the ones in the Grand Union Canal) so the effects of water ingress into the composite are practically nil, even for unpainted bikes that are frequently ridden in the rain.