Page 1 of 1

crabon fibre repair

Posted: Thu May 10, 2012 9:40 pm
by philip
So a couple of weeks ago I was JRA, rear end of the bike started to feel a bit funny, felt like the rear skewer wasn't done up properly or something because the rear wheel felt like it was moving around. So I get off my bike and have a look, seems ok, about to think it was just in my mind but then I see this (sorry for not the best quality pics.. and yes, I need to clean my bike):

Image

I went :shock: :shock: :shock: , not what I wanted to see. I rode it home (10km or so) because why not, and had a good look at it. Crabon at that point is ridiculously thin - fingernail sort of thin!:

Image

I didn't have warranty for this frame and I had heard some good things about a bloke name Stan at bike addiction in Manly. A few people highly recommended him. So I took it to him, he had a quick look and said it was a straightforward fix, picked it up today, extremely impressed:

Image

He said he wrapped 8 layers of carbon around it (it's noticeably thicker but still looks great) and said it wont be breaking there again - it looks a lot stronger than it originally was anyway!

So - if you need any crabon stuff repaired in Sydney, I recommend Stan! AAAAA++ would fix again.

Re: crabon fibre repair

Posted: Thu May 10, 2012 10:28 pm
by jacks1071
Looks like he did a great job, the origional looked very thin - can't really tell how many layers would have been in the origional from your photo but I bet its far less than 8.

Re: crabon fibre repair

Posted: Fri May 11, 2012 8:06 am
by ni78ck
lets hope the extra weight doesnt slow you down :)
glad to hear it was repairable, or else......................... :shock:

Re: crabon fibre repair

Posted: Fri May 11, 2012 8:40 am
by Ozkaban
impressed with the repair. Nice to know it can be done so well 8)

Re: crabon fibre repair

Posted: Fri May 11, 2012 9:01 am
by philip
Yeah the original looks like it is a grand total of 1 layer.

By the way, I was really impressed with the service I got from bike addiction. Their shop is excellent, they told me from the start the date it would be done by, didn't stuff me around at all, SMSd me to tell me the frame was ready to be picked up, I didn't have to follow it up or anything. Extremely good experience.

Re: crabon fibre repair

Posted: Fri May 11, 2012 9:32 pm
by ft_critical
Hi Philip,

Wish I had known. I have a friend in the Auto Carbon trade. The problem with your man "apparently" is that he over strengthens the break. Making the parts on either side vulnerable. I am not saying this as a criticism, just a warning to keep and eye out on either side of the repair. I am also just passing this on direct from my friend, I can't validate it, just took it on face. Ironically, the guy he says is best is in.... Lane Cove. How about that :roll:

Re: crabon fibre repair

Posted: Fri May 11, 2012 9:44 pm
by e466wa
Were the repairs expensive? I've always been a bit concerned with damaging my carbon frame, almost to the point of downgrading to a metal frame.

Re: crabon fibre repair

Posted: Sat May 12, 2012 12:32 am
by AUbicycles
Ft_critical, Stan is very well regarded and very experienced in this area.

I am not however, so a personal comment on the repair is that it was a critical structural fracture/break so a cosmetic repair would not be enough as the complete sections are not being replaced hence the wrapping is the most effective and cost effective solution. There could be some merit in the point that other weak points could develop however this is difficult to resolve (and return to original frame characteristics) without incurring prohibitive costs of completely rebuilding the rear triangle or buying a new frame. By wrapping, I assume that the section has been completely wrapped around rather than repaired on one side.

A very clean looking repair if you ask me, and a relief I am sure that it is rideable again.

Re: crabon fibre repair

Posted: Sat May 12, 2012 12:50 am
by toolonglegs
His repair didn't hold up for me... actually I was a bit p***ed that I got sold a frame and wasn't told it had been repaired and then when it failed they did nothing.
Mine probably wasn't as straight forward being at the drop out.

Re: crabon fibre repair

Posted: Sun May 13, 2012 9:14 pm
by philip
ft_critical wrote:The problem with your man "apparently" is that he over strengthens the break. Making the parts on either side vulnerable.
Interesting... I've spoken to a number of people who've had repairs done by him and none have had problems, except for one where it opened up in the same spot and he fixed it up again for free (as you'd expect). He told me that the places he joined it to were actually quite a bit thicker than the section he repaired, so hopefully I won't have that problem.
e466wa wrote:Were the repairs expensive? I've always been a bit concerned with damaging my carbon frame, almost to the point of downgrading to a metal frame.
I think most repairs are $400-500ish. Mine was $430.
toolonglegs wrote:actually I was a bit p***ed that I got sold a frame and wasn't told it had been repaired
that's dodgy as!

Re: crabon fibre repair

Posted: Mon May 14, 2012 5:49 am
by Ken Ho
Yeah TLL but, and I mean this quite seriously, NOTHING holds up for you, repaired or otherwise.
Maybe they just pre-repaired it for you, knowing you were gonna wreck it anyway.

Re: crabon fibre repair

Posted: Mon May 14, 2012 6:07 am
by toolonglegs
Nah I wasn't too upset... full story, 4 days before I left for France / TDF in 2006 I went over a car bonnet at a roundabout, bike went underneath. Shop had a lower quality frame of the same make that they said was a warranty replacement (or something like that)... they built it up and off I went... just gave it to me to use, very nice of them.
When I got back I had $4K to spend on a new bike. I bought back my wreck for $400 ( it was full DuraAce ) and bought my System6. Also I thought why not grab the bike I was using for a training bike... so when it fell to bits 6 months later I wasn't too worried.

Re: crabon fibre repair

Posted: Tue May 22, 2012 1:23 am
by Rex Chan
The thickness of the carbon at that point seems to be determined by the layers of carbon cloth (no core). Carbon cloth is thin, so there could be many (~6) layers there. Unless you measured it and then found out what the average thickness of carbon cloth is (Google says 0.007"/0.18mm is reasonable), you can't tell how many layers are there. And I presume the fibres would be aligned with the force direction, so you don't need a lot of carbon anyway.

To the guy who said something about over-strengthening: unless the repairs weakened the original carbon, the only "weak pint" would be how well the new carbon is bonded to the original carbon (assuming there is enough new carbon).

Re: crabon fibre repair

Posted: Sun May 27, 2012 5:43 pm
by duncanm
ft_critical wrote:Hi Philip,

Wish I had known. I have a friend in the Auto Carbon trade. The problem with your man "apparently" is that he over strengthens the break. Making the parts on either side vulnerable. I am not saying this as a criticism, just a warning to keep and eye out on either side of the repair. I am also just passing this on direct from my friend, I can't validate it, just took it on face. Ironically, the guy he says is best is in.... Lane Cove. How about that :roll:
.. this is (cough) I think !! BAN ME NOW FOR SWEARING !!.

Care needs to be taken to avoid sudden changes in stiffness / hard spots -- the repair needs to taper into the good parts of the frame well, but having the middle of the repair 'too strong' isn't a problem in itself.

You can clearly see from the after pics that the repairer has done this.. there's no obvious beginning or end to the repair.