[Closed] My DIY Carbon Frame Repair...

Some of you may remember [url= http://singletrackworld.com/forum/topic/carbon-fiber-repairs-worth-it ]This Thread[/url] Where I ended up acquiring a Broken Carbon Merida frame, I thought I'd post this follow up as I've not repaired any structural composites before, this has turned out better than I'd expected, and it's nice to share...

Here's a shot of the busted stay it when I recieved it:
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and after I stripped the finish:
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and after I dremeled out the damaged area:
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About ~ 1/3rd of the seat stay was cracked, rather than opt for the "Splodge on some gel coat and a patch" approach I've gone a bit OTT.

I took the Stay right back to the bare composite, removed the damaged section, built a support structure and then Wrapped the whole mid section of the tube several times to bridge the damage.

The Bridging was done by epoxying in an insert:

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I made this from an old bit of milk bottle (no really), this was epoxied in place and then I used a thickened epoxy to to build up support flush with the original tube.

I then laminated several layers (probably too many TBH) of Carbon on top of the support/original tube, over an area about 3" either side of the damage.

I used the poor-mans, electrical Tape compression method rather than proper vacuum bagging, as I simply didn't have the kit, it's probably quite resin rich as a result, but I'm relying more on the quantity of additional material and the large area of the repair "Splint" to transfer loads safely. I didn't take any pictures of this bit as I was a bit too busy and didn't fancy getting resin all over my phone...

This is how it eventually turned out:

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A bulky but not too shabby repair IMO.

Assembled bike (with seriously neglected garden):

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Rather than paint over the repair I've just wrapped both stays in cheap reflective vinyl for now which I can peel back to inspect the repaired area should I need to later.

It's first Shakedown ride was on Saturday, I was expecting to hear cracking and creaking noises from the back end, not a bit of it, 27 odd miles with the tyres pumped up too hard, clattered it through a pot holes and over rough surfaces and bunny-hoping over a few drain covers, not a peep from the frame, it feels pretty good...

Buying the frame and repairing it has probably cost me about ~£120 (I did have most of the material to do it beforehand), so it was a worthwhile exercise. Though it was mostly a fun "Learning exercise" TBH... We'll see how it's going in 1000 miles.