Recommended epoxy/adhesive for carbon frame repair?

[guylimey]

Any recommended epoxy/adhesive for carbon frame repair? Not a significant repair, a short (just over 1/4 inch) hairline crack in one chain stay but I have carbon fiber sheeting and would like to patch the area but need to know what epoxy/adhesive to use. Thank you.

[Black Dog]

West System. Widely used for kevlar and carbon fibre in high stress marine applications. For any serious structural repair I would ask one of the carbon builders on this site for advice on adhesives.

https://www.westsystem.com

[zmalwo]

Make sure you mix them thoroughly, or you get spots that never hardens from the resin that wasn't mixed with enough hardener.

[Mikej]

You're not going to fix it by gluing it. You have to clean up the ends on the crack and remove any delaminated material, replace material and re epoxy.

[zmalwo]

just sand the whole chain stay and wrap more than 5 layers of carbon and you are set. no need to worry about weight at this point you want that thing layered up like a tank to the point it's almost solid carbon.

[11.4]

A crack in a chain stay? Ummm, send it to a professional frame shop such as Calfee or Parlee (or to the original maker if it's a custom frame) for a proper repair. Just wrapping and gluing it isn't going to do much.

[muz]

Originally Posted by zmalwo

just sand the whole chain stay and wrap more than 5 layers of carbon and you are set. no need to worry about weight at this point you want that thing layered up like a tank to the point it's almost solid carbon.

This won't work, at least not for long. As others suggested, you need to sand down to carbon first. Then you need to apply several layers, starting with a small patch and then extending the next layer another cm on each side, etc. Otherwise you create a stress riser and it will crack at the transition from the patch to the original chainstay. This won't be pretty, but it will probably work.

[ergott]

I'm sending my post crash frameset here for eval and discussing any possible repairs. I think the bike is fine, but not worth it to take a chance.

https://www.ruckuscomp.com/

[commonguy001]

I’d check with Drew at Cyclocarbon in Rochester MN and get his thoughts. He is on Facebook and posts a number of his projects on Instagram. He also puts on a few gravel races in southern MN, a solid guy who does a goood job.

[Bruce K]

I highly recommend Ruckus

Good guys with lots of experience and know-how

BK

[AngryScientist]

if it were my bike with a similar issue, i would absolutely undertake a repair myself.

i do not buy into the internet alarmists who tell everyone that you have to get a "professional" to repair anything.

The OP has taken a good first step and is asking a question before jumping into a repair, although the actual repair is probably going to be a little bit more involved than the simple question asked in the original post - an at-home carbon patch is absolutely possible. People have been DIY'ing fiber stuff for years, it's not as if we're trying to build a lunar rover in the garage here.

do a little more research guy, in the area of surface prep, carbon fiber repair, compatible epoxies, etc. with the internet at your literal fingertips, all the information and supplies are readily accessible for a successful repair here.

[prototoast]

This should be fine, I've used it before: https://rover.ebay.com/rover/0/0/0?m...2F111598779395

Most important thing is to make sure you get an epoxy resin, measure the quantities accurately, and mix well.

Don't mix too much at once or you can start a fire. You won't need much for this project, so I'd advise to mix up no more than 50ml at a time. This time of year, if your workspace isn't heated, you'll want to add some heat to help it cure. For a room temperature resin, you won't need to nuke it, but get it up to 80-100f.

For a hairline crack in a straight stay, it should be pretty easy to lay the carbon fiber, and get good compaction with perforated heat shrink tape like this: https://compositeenvisions.com/hi-sh...ated-1633.html

Surface prep is very important. Make sure you sand and clean with acetone and alcohol first. Wear a mask and do it outside if you can, because carbon fiber dust is bad for you.

If you happen to live in the SF Bay area, pm me and I might be able to help.

[guylimey]

Thanks for all the feedback everyone. Not intimidated by the repair just want to use the right materials and prep correctly.

[glepore]

Carbon repair? No need to be afraid. The ebay resin above is fine, most of the ebay sellers are simply repacking industrial resin. Sand well. There's likely filler and primer etc. Clean with acetone. Saturate the cloth and lay in place, then wrap tightly. I usually use scotch blue masking tape, electrical tape works as well. There are specialty wraps the suppliers sell with perforations to allow resin to seep through, but these are mostly unnecessary with small repairs. Allow to set for 24 hrs or so indoors, remove tape, sand smooth, repeat.

I've repaired frames, parts and even Lightweight wheels this way.

[SoCalSteve]

Originally Posted by ergott

I'm sending my post crash frameset here for eval and discussing any possible repairs. I think the bike is fine, but not worth it to take a chance.

https://www.ruckuscomp.com/

Sent you a PM regarding Ruckus. My recommendation is to send it elsewhere, they are very incompetent. If you search them here you will see mine and others document just how incompetent they really are. Good luck!