Fixing Scott CR1 bottom bracket aluminum insert

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Westbank
Posts: 321
Joined: Sun Apr 03, 2005 4:39 pm

by Westbank

I have a 2005 Scott CR1 on which the bottom bracket aluminum insert (on the crank side) has came apart. It appears that the aluminum insert was glued to the carbon fiber bottom bracket shelf.

I think this can be easily repaired with epoxy. That being said, I wanted to know what type of epoxy I should use to glue aluminum to carbon fiber ?

Here's the part that came apart (insert pointed by the arrow):
Image

Cheers !

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Westbank
Posts: 321
Joined: Sun Apr 03, 2005 4:39 pm

by Westbank

Can someone confirm if this epoxy glue will do the job ? (PermaPoxy)

Image

by Weenie


progetto
Posts: 17
Joined: Wed Feb 01, 2012 9:12 pm

by progetto

There is a lot of force going into the shell. To do it properly the aluminium shell will need to be removed and reinstalled with something like 3M dp 470, but it will be a major job to get the shell out as i believe it is a two piece shell inserted from each side and glued together at the joint. Anything else you do will be a band aid solution.
Bill

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Westbank
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Joined: Sun Apr 03, 2005 4:39 pm

by Westbank

Thanks Progretto.

I was able to completely pull the insert on the drive side (the one that came apart).
For the 3M glue, are you referring to this one : http://www.shop3m.com/3m-scotch-weld-ep ... 36qpz.html. Didn't find anything about the DP470.

twigstim
Posts: 43
Joined: Thu Aug 11, 2011 6:36 pm

by twigstim

This happened to my friends CR!, I believe his was a 2005 as well. He tried the epoxy method but didnt quite trust the adhesive. He ended up contacting scott and they sent him a brand new CR1. Have you tried simply looking to get a replacement?

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Westbank
Posts: 321
Joined: Sun Apr 03, 2005 4:39 pm

by Westbank

The frame is not covered by the warranty anymore.
I'll probably try and see how it holds.

veloflyte
in the industry
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Joined: Sun Sep 27, 2009 3:08 am

by veloflyte

I've been working with carbon fiber for many years now...as you may know from the carbon items I produce for bicycles...Veloflyte.
Getting a strong bond to metal relies heavily upon the surface preparation of the metal. In your case however since the metal edge to be bonded to is hidden, the best thing you can do is choose an epoxy with the best bonding properties. The epoxy you have pictured is very low quality. I would not recommend using that type and brand. I do recommend you use Devcons Plastic Steel epoxy. It comes in a similarly sized container and will bond to metal much better than the epoxy you have in the picture.
The picture of your frame does not show the problem at all. I'm not sure how wide the "gap" is.

progetto
Posts: 17
Joined: Wed Feb 01, 2012 9:12 pm

by progetto

Sorry, mean't dp 420.

by Weenie


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