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Ouch!!

Posted: 23 Sep 2014, 7:58pm
by neilob
I have just realised the frailty of carbon fibre frames. In the middle of changing the chainset on my winter bike, dinner was announced. I quickly hung the bike up on its pegs above my beautiful new carbon road machine. But I hadn't bolted the chainset on and it came off as I was lifting the bike up, dropping tooth first onto the bike below. I'm guessing it has ruined my new road machine as it has pierced the paint finish and the tubing. Do experts exist that can repair these frames or is it cut them up and throw away??

Re: Ouch!!

Posted: 23 Sep 2014, 8:05pm
by yostumpy
I'd be inclined to drill it out in to a hole just larger than the damage. holes are very strong, much stronger than a 'peirced hole' with a jagged edge. Then just stick some gaffer tape over the hole, and see how you you go.

Re: Ouch!!

Posted: 23 Sep 2014, 8:15pm
by fastpedaller
Has that gone through the tube?
Crikey I didn't realise they were that fragile.
Can't beat a bit of steel. I HAD a nice Rondinella Neil, but it sold yesterday -£450 .... so sorry to see it go. Like losing a pet.
Have the cash for the Spa tourer now!

Re: Ouch!!

Posted: 23 Sep 2014, 8:23pm
by fastpedaller
You can buy epoxy resin and cf cloth from East Coast Fibreglass or similar, but doing a good (invisible) repair may be another matter. I've not used cf, but have done a fair bit of stuff in glassfibre (built a folding caravan with it from scratch). It (cf) usually needs vacuum and autoclaving to manufacture. I should think if you were to produce a 'sleeve' by laying up wetted cf and clamping 2 halves of a 32mm I/D tube about 2" around whilst it cures you could repair it - but it may not be good on the eye.

Re: Ouch!!

Posted: 23 Sep 2014, 9:46pm
by RickH
There seem to be quite few CF frame repairers (Google search results) around these days. I've no idea how much it is likely to cost & it all depends on the value of the frame too.

I must admit I was impressed by the quality, visually at least, of Calfee's repairs over in the USA when I was looking at their site. That was prompted by meeting an American couple on one of their S+S coupled CF tandems when I was in Wharfedale for the TdF in July.

Rick..

Re: Ouch!!

Posted: 23 Sep 2014, 10:48pm
by Edwards
I think that the normal position on this forum is that Carbon Fibre frames explode if the is the merest scratch or mark in the paintwork. This is done without any warning and people will die.

If the bike were mine after I had finished swearing then crying I would be looking for a professional service that could advise and hopefully repair the dent.
I do not think that I could bring myself to cut the frame up.

Re: Ouch!!

Posted: 23 Sep 2014, 10:59pm
by JohnW
fastpedaller wrote:..........I didn't realise they were that fragile.
Can't beat a bit of steel...............Have the cash for the Spa tourer now!


I can only endorse that.

I'd say that the advice that Edwards gives, about getting professional advice before you do anything else, is good and sound.

Best of luck with it - and with your future custom built steel frame. :lol: :lol: :lol:

Re: Ouch!!

Posted: 24 Sep 2014, 4:20am
by tim-b
Hi
I don't own a CF bike so this isn't a personal recommendation, however I hear that http://www.carboncyclerepairs.co.uk/index.html do a good job
The National Forest is a pleasant area for a cycle around while they do their thing
Regards
tim-b

Re: Ouch!!

Posted: 24 Sep 2014, 10:27am
by [XAP]Bob
Edwards wrote:I think that the normal position on this forum is that Carbon Fibre frames explode if the is the merest scratch or mark in the paintwork. This is done without any warning and people will die.

If the bike were mine after I had finished swearing then crying I would be looking for a professional service that could advise and hopefully repair the dent.
I do not think that I could bring myself to cut the frame up.


That's taking the "forum position" (if there is such a thing) a little far (but hyperbole is amusing nonetheless).

However, you *do* know that the CF is damaged, what you *don't* know is how badly...

For that a professional opinion is more valuable than mine. I'm sure you could cut it off near the seatpost and head tube and bond a proper steel top tube in place :lol: :lol: :lol:

Re: Ouch!!

Posted: 24 Sep 2014, 11:09am
by Edwards
[XAP]Bob wrote:That's taking the "forum position" (if there is such a thing) a little far (but hyperbole is amusing nonetheless).


It was not meant to be that serious but having read the threads is not that far of the mark with regards of some of the comments. :roll:

I forgot to say that if the bike is my size I volunteer to take my life in my hands and do a long term test to see if it is safe for you to ride as is. :D

Re: Ouch!!

Posted: 24 Sep 2014, 1:20pm
by DavidT
First of all, massive sympathies to the OP for the damage to the frame - through a moments oversight. Been there and done that. Horrid experience!

However I'm amazed at the suggestions on here that indicate that some form of formal engineering review is apparently needed to ensure the frame is not irrevocably damaged? - From a dint like that?!

I have no reason or competency to doubt or question such concerns, but if they are truly the case then this thread must surely represent the best case for steel frames ever (or at least the need to avoid CF)

Happy cycling

Re: Ouch!!

Posted: 24 Sep 2014, 1:49pm
by [XAP]Bob
DavidT wrote:First of all, massive sympathies to the OP for the damage to the frame - through a moments oversight. Been there and done that. Horrid experience!

However I'm amazed at the suggestions on here that indicate that some form of formal engineering review is apparently needed to ensure the frame is not irrevocably damaged? - From a dint like that?!

I have no reason or competency to doubt or question such concerns, but if they are truly the case then this thread must surely represent the best case for steel frames ever (or at least the need to avoid CF)

Happy cycling


This is exactly why many people are so unsure about CF as a long term material. Steel (and to an extent other metals) might still be damaged, but the final failure (if triggered) tends to be more graceful (and therefore much safer).

The CF might be just fine, but it might not be, and the material isn't easily understood by simple observation. Combined with the tendency to fail without warning it's just not a material that inspires confidence that a bike will last 20, 30, 40+ years.

Re: Ouch!!

Posted: 24 Sep 2014, 4:25pm
by [XAP]Bob
http://www.bustedcarbon.com/2011/07/jra ... loded.html

Note that most things on BC are "hit with a car" or "racing and got pushed into a barrier"

But there are also these "JRA" incidents


(JRA - Just Riding Along)

Re: Ouch!!

Posted: 24 Sep 2014, 5:50pm
by foxyrider
Good carbon frames have wall thicknesses much thinner than aluminium, comparable to steel, how thick did you all think the CF tubes are? I think there is a fair chance that my superlight Columbus steel frame would suffer similar damage to the OP's carbon fibre.

This isn't a failure, this is accidental damage so all those jumping on the 'steel is best' soapbox can return to their high horses!

Re: Ouch!!

Posted: 24 Sep 2014, 7:37pm
by neilob
As a number of you imply, I should feel really sick at my stupidity in allowing it to happen. And I do. I've moved past steel apart from my Thorn tourer, but I do have this nagging doubt (which has been well expressed above) that its what you can't see with carbon that's the problem. I can't imagine feeling confident hitting 40+mph on a twisting descent on that frame knowing the little I know about catastrophic failure modes of carbon fibre frames. So I will probably cut it up and bin it rather than see it somehow return to use. A shame but its the only decent thing to do.