Help! Carbon fiber (UPDATE)

[bianchi10]

Long story short, bought brand new superlogic carbon bars today. Used acetone to take off a to logo and it MUCKED up the carbon! Sanded off the matte clear and naw it's smooth and down to raw carbon. Almost finished with it.

So I spray a matte finish clear coat protectant on it or leave it? I don't want it to be sticky at all on the top bar. I bought some rustoleum advanced matte clear. Just don't know if I should use it or if there is no need.

Kicking myself in the fave right now for ruining $300 bars 10 minutes after getting them home.

[cadence90]

Definitely sand carefully with 600/800 wet/dry; clean very well with soap/water; rinse; dry very well; and then re-spray with several light coats of a good clear coat. Apply the second and third coats within the listed re-coat time.

I would actually recommend a more durable clear such as SprayMax 2K. This is a 2-part clear with a built-in catalyst. It is easy to apply and extremely durable when fully dry. The problem is that once the catalyst is introduced to the clear, you must use it within 48 hours maximum (after that everything inside the can turns solid).

That said, SprayMax do make a good 1K (1-part) clear which is quite good and actually would be fine for bars, etc. It has no catalyst, so it can be stored/re-used indefinitely after the first use.

Both can be found in many auto paint stores.

SprayMax 1K Clear coat.

SprayMax 2K Clear coat.
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[dgauthier]

Originally Posted by bianchi10

... (now) it's smooth and down to raw carbon...

Exactly what to you mean by "raw carbon"? If you've exposed the carbon fiber reinforcement, you may have rendered the bars unsafe to use. Would you care to post a picture of the damage before you spray paint over it?

[R3awak3n]

I don't remember what I used for my carbon brake levers but can check for you. I think was some sort of rustoleum matte clear coat.

Not sticky at all but after using the levers regularly I can see difference in texture (where I use them more they are shinier), I think it will probably have to be re applied eventually.

[bianchi10]

Here are some photos. Again, this was JUST normal acetone and a microfiber towel. Wasn't GOING at it, just an easy rub trying to get the two smaller decals off the backside. As I was rubbing, I felt a small ridge as I went back and forth. pulled the towel away and say that it had gone through the clear. Immediately felt sickened, but took it outside in sunlight to get a better look. Sunlight hit it and I could see this green appear. Almost as if the sunlight ignited the chemical reaction to turn it color. let it sit for a while in the garage and when I came out it was even worse. Was ready to pull the trigger on another set (Only because I knew I wouldn't allow myself to ride with these bars), when I figured at this point, I have nothing to loose and try and sand this top bar section down. Might be hard to see in the last photo, but what I meant by "raw carbon" is that you can now see the directional layers of the carbon. I used a 1000 grit to get down past the clear coat I had already gone through with acetone. Took a lot of time, but I didn't want to rush it with a 400 or 600 grit and possibly risk taking off more than I wanted too quickly. The carbon is sanded down pretty even and I think at this point, once they get wrapped, I'd at least be ok with it for now since the entire top bar (or at least all you will see after wrapped) is the same "raw" look.










This is the clear coat I bought. It was $8 and told that it was much better than the standard Rustoleum style protectants. Has a UV protection and is supposedly very durable. I haven't used it yet so I can easliy return and go to an auto shop and get something that will be more durable if recommended. I wouldn't mind getting some sort of "cloudy" or "Mist" clear to maybe help cover up some of the imperfections of the carbon lay. What do you think?

[ultraman6970]

You can use acetone in steel tubes but i wouldn't do acetone in carbon ever, it is too hot and if you look at it you still have the logos in there and the carbon turned green... Carbon you have to sand it, if you sand and need to clean afterwards using rubbing alcohol.

If your want those logos gone you have to sand.

Regarding the clear, if your budget is 8 bucks you can use that clear but to be honest I would just go and try to get the spraymax 2000 recommended, expensive? hell yes but is real car grade polyurethane clear coat, and probably way better than the one that was in the parts you cleaned. I have no idea if they have satin finish but what you can do is to spray 4 coats of glossy, and then scuff it with 2000 grit wet sand paper, in that way you get the satin effect you are looking for. Once you activate the can the clear wont last more than 24 hours, after that period of time the clear is useless.

That clear use an activator, basically the can has like 2 parts, clear and the activator, once they are mixed the chemical reaction starts happening. Polyurethane doesnt dry by air but dries by chemical reaction, thats why takes just hours to be ready to the touch, not like rustoleum stuff and that eventhought lately got better than before, it needs air to dry.

Hope this helps.

ps: give a try to that 8 bucks clear, u lose nothing, just spray mists of it, dont do wet coats with that thing.

[bianchi10]

Originally Posted by ultraman6970

You can use acetone in steel tubes but i wouldn't do acetone in carbon ever, it is too hot and if you look at it you still have the logos in there and the carbon turned green... Carbon you have to sand it, if you sand and need to clean afterwards using rubbing alcohol.

If your want those logos gone you have to sand.

Regarding the clear, if your budget is 8 bucks you can use that clear but to be honest I would just go and try to get the spraymax 2000 recommended, expensive? hell yes but is real car grade polyurethane clear coat, and probably way better than the one that was in the parts you cleaned. I have no idea if they have satin finish but what you can do is to spray 4 coats of glossy, and then scuff it with 2000 grit wet sand paper, in that way you get the satin effect you are looking for. Once you activate the can the clear wont last more than 24 hours, after that period of time the clear is useless.

That clear use an activator, basically the can has like 2 parts, clear and the activator, once they are mixed the chemical reaction starts happening. Polyurethane doesnt dry by air but dries by chemical reaction, thats why takes just hours to be ready to the touch, not like rustoleum stuff and that eventhought lately got better than before, it needs air to dry.

Hope this helps.

ps: give a try to that 8 bucks clear, u lose nothing, just spray mists of it, dont do wet coats with that thing.

Great! thank you for the help. I'll return this stuff then and go look for the spraymax. Much appreciated!

[dgauthier]

Yeah I must say you look okay there. You got through the clear coat and down to the *plastic*, not down to the carbon.

That being said, I'm surprised by your "this was JUST normal acetone" comment. Would you rub acetone on the dashboard of your car? Acetone is a powerful solvent that dissolves many paints and plastics.

[bianchi10]

Originally Posted by dgauthier

Yeah I must say you look okay there. You got through the clear coat and down to the *plastic*, not down to the carbon.

That being said, I'm surprised by your "this was JUST normal acetone" comment. Would you rub acetone on the dashboard of your car? Acetone is a powerful solvent that dissolves many paints and plastics.

Yeah I've taken acetone to so many bike parts without an issue. Because of that, I didn't think twice about having problems with these. Lesson learn. Expensive lesson learned.

[dgauthier]

Originally Posted by ultraman6970

(...) if you sand and need to clean afterwards using rubbing alcohol.(...)

Do *not* use rubbing alcohol! In Googling around for this thread I discovered that while it seems acetone will not dissolve fully cured carbon fiber resin, alcohol-based solvents are used to dissolve some resins when recycling carbon fiber:

https://www.cnet.com/roadshow/news/b...-carbon-fiber/

http://www.rh.gatech.edu/news/554601...s-reduce-waste

I have to say I would have tried rubbing alcohol to remove a logo. Thanks to this thread now I know better. Possibly the clear coat would protect the carbon fiber resin and keep the alcohol from ever making contact. However, if you're sanding through the clear coat and exposing the plastic resin, cleaning up with alcohol is a very bad idea.

Ya learn something new every day. Keep *all* solvents off carbon fiber parts!

[ultraman6970]

Well when you sand you have to take the dust out, acetone too toxic but regular alcohol will do the trick, is not that you will submerge the pieces for 5 hours in alcohol, just a towel with a tiny bit to get the dust out...

The reason of the clear coat is to protect the carbon of UV ligt, UV light kills carbon big time, advice... if you have a carbon piece that is turning yellow is because the clear is failing... time to sand and reclear...

[many_styles]

Why not just run more bar tape? Do you ever ride on the tops of your bar?

[bianchi10]

Originally Posted by many_styles

Why not just run more bar tape? Do you ever ride on the tops of your bar?

I re-used my bartape from my last bars. These new vars have a much larger diameter top tube so the tape didn't go as far. I have ordered new tape and will go further in with the new tape.

[many_styles]

[cadence90]

Originally Posted by bianchi10

I re-used my bartape from my last bars. These new vars have a much larger diameter top tube so the tape didn't go as far. I have ordered new tape and will go further in with the new tape.

I would still re-clear the bars before using them.

Also, as has been stated previously, do NOT use acetone or other solvents on carbon-fiber. Instead, use a single-edge razor blade, perpendicular to the surface you are removing, and gently scrape back and forth until the top clear + decal is removed. This allows you to stop before penetrating any of the actual c-f/resin, and is a much faster/safer/cleaner method.