Bicycle Mechanics - Need suggestions for polishing a carbon fiber frame

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Dablue
09-08-10, 03:14 PM
Hi Guys,

I've just bought my first (second hand) carbon fibre road bike.

The frame needs a clean but it also needs reviving. There are patchy areas on in where it's hazey / foggy, it almost looks dirty but it's completely clean.

I've read through a couple of threads already...

http://www.bikeforums.net/showthread.php?526702-Carbon-Fiber-Cleaning-and-Polishing&highlight=carbon+polish
http://www.bikeforums.net/showthread.php?229186-A-Great-Polish-for-Your-Carbon-Bike

Just wondering if anyone else could throw their thoughts... there seems to be quite varied list of suggestions.

Thanks in advance,

Mike


clydeosaur
09-08-10, 08:10 PM
Compound , polish & seal/wax. If some parts are pretty bad, perhaps some 2000 grit wet sanding, followed by the compound & polish. Either way, time to start rubbing. Either that or have it stripped to bear frame, prepped & clear coated by a body shop.

dabac
09-09-10, 02:51 AM
Compound , polish & seal/wax. If some parts are pretty bad, perhaps some 2000 grit wet sanding, followed by the compound & polish. Either way, time to start rubbing. Either that or have it stripped to bear frame, prepped & clear coated by a body shop.

+1

You're not (or, you shouldn't be!) working on the actual CF, but on the cleatcoat on top. So while we all may have our personal favourites pretty much any product meant for glossy painted surface should do. Car paint restorers/conditioners, rubbing compunds and waxes for boats etc.
But sand paper, even at 2000 grit, takes some experience. You don't really know how thick the clearcoat is to start with.


HillRider
09-09-10, 06:36 AM
My Kestrel carbon fork came with a very explicit instruction sheet saying NEVER use paint strippers, never sand away any of the structural fiber. They recommend "hand sanding" (grit not specified) to just scuff the topcoat and don't bake at over 150 F if you want to paint it or redo the clearcoat.

constant mesh
09-09-10, 07:15 AM
If you indeed have to sand it, go with WET sandpaper and use water as lubricant.
Otherwise, any Meg's or 3M polishing compound will do, just don't buy anything that is generic or advertised like there's a magician trapped in that tube at department stores or gas stations. You will only need a finishing paste, cheap ones are usually too coarse for that.

Dablue
09-09-10, 08:29 AM
Thanks for the feedback guys.

I have to say the thought of doing any sanding on it spooks me :eek: although I have read it several times now.

Think I will try the rubbing / polishing compound first.

I tried using some good quality car polish last night and it didn't do anything. It didn't make it any worse or better.

Will drop the manufacturer an email and see what they recommend too.

Cheers guys

nhluhr
09-09-10, 12:42 PM
Don't do any sanding. Do polishing. Meguiars makes some good products for this.

Rob_U
09-09-10, 01:17 PM
+++1 on the Meguiars, they make a range of polish/rubbing compound products (http://www.meguiarsdirect.com/products/professional_care/mirror_glaze_page2) that I have used on my Trek 7.5FX (painted aluminum), automobiles with poly finishes, and guitars with poly, and lacquer finishes. The Swirl Remover, a final polish and some elbow grease are all you usually need. Just clean with water between product grades. If need be you can use their Fine or Medium cut cleaner first, just remember to follow with the swirl remover, and wax. On my Trek I had to remove stains left behind from Yakima rack straps - it's now smoother than new. I first read about them in a guitar magazine, one of the top guitar repair techs swears by them.

JTGraphics
09-09-10, 01:27 PM
Thanks for the feedback guys.

I have to say the thought of doing any sanding on it spooks me :eek: although I have read it several times now.

Think I will try the rubbing / polishing compound first.

I tried using some good quality car polish last night and it didn't do anything. It didn't make it any worse or better.

Will drop the manufacturer an email and see what they recommend too.

Cheers guys

I used some 1000 grit sand paper to remove a small scratch in carbon and polished with wax can't even tell.
But I'd be more spooked on buying a used CF that is in such condition that you need to do what you are. That fog could be some type of problem with in the resin
Carbon frames and forks are one thing I'd never buy unless I knew the person I was getting it from and I know how it was treated, but thats me.

Dablue
09-09-10, 04:16 PM
But I'd be more spooked on buying a used CF that is in such condition that you need to do what you are.

Yeah, I got a great deal on it and structurally it's fine and it rides great. It does't look like its hardly any use. It was a young kid who I bought it off and he didn't clean it up.... I think most people would have taken care of this before selling it to get a good price.

Even if I can't make it tip top I wouldn't be overly bothered, not for what I paid for it.

Looking at Meguiars now...

clydeosaur
09-09-10, 05:13 PM
You can sand, but I should have cautioned you. You should be familiar with fine wet sanding. I've done a bit of painting (mainly automotive) and have some experience working with sanding/polishing. I'd say it's a safe bet you have the same 2k clear on your bike as you do on your car, unless it's just sealed in epoxy.

Greenfieldja
09-10-10, 06:53 AM
buy some stickers or decals and just lay them over that area and call it good. It will make the bike look personal and give it character and you wont have to waste your time wetsanding and polishing something that you should be out riding.

-j