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Discussion Starter #1
Not a mtb and its a carbon fiber frame but thought I would come here for some much needed technical advice.

I caught my cable end bracket on my carbon road bike frameset on the bike rack and it broke the glue bond underside the aluminum bracket where it joins to the carbon down tube just aft of the head tube. This has resulted in dodgy shifting and the good story there is I would adjust rear shifting for one ring and it would be different for the other ring because change in front derailleur cable tension would rotate the bracket about 1/4". Took me a while to figure that out...longer than it should have :)

So next step is to drill out the rivet. Downtube and bracket are still in pretty good shape...and rivet is still intact...but not enough gapping to fill with high viscosity epoxy nor a good rivet pull any longer. Will have to tear the frame down of course because I will be drilling into the down tube and then re-riveting. Reading about attaching cable stops to carbon tubes reveals that regular JB Weld works good once mating surfaces are clean and scuffed.

But what kind of rivet do you suggest? Any rivet experts in the house? Reading on the web...carbon is a bit more fragile to rivet to...basically an epoxy matrix...maybe a standard cherry rivet would work but would a tri fold rivet be better for securing to the carbon tube under the bracket?

I would prefer to fix this myself versus say ship the frame off to Calfee in California or another frame builder.
Thanks in advance for any help you could provide.



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Gabe.....
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"JB Weld works good once mating surfaces are clean and scuffed"........this would be the ticket. I've seen amazing stuff done with JB weld.......keep it simple, my .02 :thumbsup:
 

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Discussion Starter #3
Speaking of keeping is simple.... guess I could 'inject' JB Weld once mixed with a dispensing syringe between the gapped bracket and then clamp it and not change the rivet. This wouldn't allow good cleaning and scuffing though.
Any suggestion on a good rivet for carbon fiber?..no access to backside in the down tube.
 

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Discussion Starter #5
customfab said:
I've seen many manufactures warranty carbon frames for busted cable stops. I would start there then tear into the home grown solutions.
Thanks. I contacted Look USA surveying my options. To be clear, the damage is my fault. I am a careful guy and this frame has never been crashed...but the frame fell off the wall stand and apparently caught on the cable stop and broke the bracket glue bond. Took me quite a while to discover this and only figured out the problem when I couldn't dial in the shifting.

Look responded with some DIY suggestions which agreed with Calfee. They offered to take the frame back...no replacement offered...however offered to repair it however stated it would take several weeks for return...and presume I would incur transit costs and perhaps more at a minimum. I didn't want to part with it that long approaching spring riding.

I therefore opt to fix it myself. A reasonable endeavor really. Prep is the key and now I have my repair strategy mapped thanks to all of the good advice I have received.
Cheers.
 
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