Stripping and painting carbon fiber?

Re: Stripping and painting carbon fiber? (SP3)

If the paint is sound and compatible with the new product you're using, and you're not having any adhesion problems, you'd be better off not stripping it at all. Check for compatibility and solvent lifting by doing a test patch; if the new paint doesn't lift the old, you're golden. Existing, adhering paint provides a sound and preferable foundation...

Sand it down to achieve a surface profile sufficient to allow the new coating to adhere. You want to get through any clear and into the color coat. If it's only clear coated, then sand that.

You want to start w/ 120-240 grit, then sand w/ 400 grit prior to your first color coat. From there, go progressively finer until your clear coat. Color coats can be sanded w/ up to 600-800 grit, and use 800-1000 grit between cclear coats.

If you start from scratch by stripping it down completely, you're opening the door to a lot of problems that have essentially already been solved for you.

Re: Stripping and painting carbon fiber? (DesmoBob)

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by DesmoBob »</TD></TR><TR><TD CLASS="quote">If the paint is sound and compatible with the new product you're using, and you're not having any adhesion problems, you'd be better off not stripping it at all. Check for compatibility and solvent lifting by doing a test patch; if the new paint doesn't lift the old, you're golden. Existing, adhering paint provides a sound and preferable foundation...

Sand it down to achieve a surface profile sufficient to allow the new coating to adhere. You want to get through any clear and into the color coat. If it's only clear coated, then sand that.

You want to start w/ 120-240 grit, then sand w/ 400 grit prior to your first color coat. From there, go progressively finer until your clear coat. Color coats can be sanded w/ up to 600-800 grit, and use 800-1000 grit between cclear coats.

If you start from scratch by stripping it down completely, you're opening the door to a lot of problems that have essentially already been solved for you.

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that's some good info ,make sure that you clean the surface with a good wax and grease remover, but on carbon or fiber glass products that have been painted already ,, just color sand with180- 240 if you are going to primer , 360 if you are going to use a primer sealer and 400 wet ( add a few drops of dawn dish soap ) if you are going to color coat over the exhisting color ,do not forget to use a foam sanding block too,, here's the fun part ..
if you begin to sand and you get colored water righ off the bat then it's a single stage paint ( no clear ) then you should put down a sealer or a primer sealer to prevent any solvent lifts ( wrinkles) . if you don't get any colored water then , make sure that you sand as flat as possible ,, 90% of the paint in the U.S. (is weaker than the Euro counter parts ie, Sikens & Glauserat just to name a few ..)
can be used over exhisting clear coat paint jobs ie , Dupont ,PPG , Sherman Williams ,Rm,Nason .. just watch for flash time ( between coats ) follow mixing instructions ( most store are more than willing to help ) .. generally you shouldn't have to sand the base coat (between coats ) unless you really screw up ,, most manufactures recomend three coats to full coverage .. depending on weather ,, 15 to 25 minutes between coats .. clear coats ,, be it a 2 to 1 mix , 3 to 1 or 4 to 1
( the last is easyest for beginers) 3 coats max to prevent solvent trap and dye back ( hazing ) again .. flash time is important . any reputable paint store should be able to answer any of your questions and help you out ... i do it day in and day out

Re: Stripping and painting carbon fiber? (04749s)

Everything 04749S said is exactly correct; a few more details, and important ones. I'll add one more that I should have thought of before: humidity.

If the humidity wherever you're working (if not controlled, then the ambient humidity outside) is anywhere near 50%, DON'T clear coat! You really want it as dry as possible...I've gone so far as to use a portable dehumidifier in my workspace.

If the humidity is too high, moisture will basically be attracted to the cooling effect created by the solvents flashing out of the clear coat, and will become trapped in the film as it dries. If this happens, the whole surface will haze; it'll look like frosted glass. This phenomenon is called "blushing", and if it happens, there's no way to fix it. You have to sand back down to the color coat, apply more coat(s) of color, and re-clear. NOT fun.

BTW, to clean the dust off after sanding, you can use soap and water; effective, but you have to wait for it to dry; you can use a "tack rag" available at any car parts store (but I don't really trust them...I think they may leave a residue, though I have no first-hand knowledge of this happening), or a "pre-paint wipe" or "paint-prep" wipe, which is just a cloth in a foil pack saturated with a high-grade, very fast evaporating solvent. This not only cleans up the dust residue, but also slightly "softens" the prior coat, ensuring a good chemical bond.

Okay, that's it. Sounds like 04749S has some experience; until last Friday, I had 18 years in the paint industry, working in various capacities for a large east coast coatings manufacturer--including Regional Technical Rep. Now, of course, I'm running the machine shop and the high performance, special fabrications, and racing development programs for a H-D/Buell dealership. So again, it's just my