So just over a year ago I crashed and put a small crash in the drive side seat stay. It wasn’t too bad – about 2 inches long and bare’t noticable. It was actually along the seam of the carbon tube. Luckily I have a friend with a lot of carbon fiber experience, so after purchasing the 2-part epoxy I loaded up and drove for 4 hours to his house to do the repair.
The first step was to sand the clear coat off all the way around the tube extending over an inch past the repair area.
Then, with the disc attachment on a dremel I then opened up the crack a bit to ensure that the epoxy would penetrate the area. A sheet of carbon fiber was then cut to the length of the tube that I prepared and to a width so that it would wrap the tube 1-1/2 times. This sheet was then “painted” with the epoxy using a paint brush but ensuring that the epoxy was pushed in between all of the cross fibers of the cloth. The cloth was then wrapped around the tube, then a bit more epoxy was painted on. At this point I had to wrap the repair with this shrink tape starting at the bottom of the tube so that it wound around it and ended at the top. The top and bottom of this tape was taped into place with packing tape. Finally, I used an industrial heat gun to heat up the tape on all sides of the tube so that it shrunk tight. Some epoxy dripped out the bottom and once it was all tight and the epoxy stopped flowing it was time to wait for it to cure. I waited about 16 hours. Here it is with the tape still on it before I took it off.
Then I unwrapped the tape and saw this:
At that point I had to sand it to get everything smooth and then spray it with clear coat. Done. It was suggested that I paint the repair area black and then clear coat it and then nobody would be able to tell that it was ever repaired, but I like the look of it.