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Jul 10, 2019, 03:23 PM
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How do you paint a fiberglass cowl?


I am trying to get better at painting and need some simple advise. I am going to paint a fiberglass Specialties cowl and wheel pants and am using Rustoleum spray paint. So far I know to sand down with 220 grit before primer coat and 320 between color coats and use wax and grease remover solvent after sanding between coats and clean with a microfiber cloth and tack cloth, but here's my questions.

1. How long can I leave the 3m low tack blue masking tape on (60 day release)? Do I need to remove it between coats of paint and reapply or can I just leave it on until done with that side of the color?

2. After I get done painting both colors, can I do my final 600 grit sanding over both colors at once or do I need to sand up to the color separation lines carefully before clear coating? Can I just sand lightly over the paint without worrying about the colors running into each other?
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Jul 10, 2019, 07:30 PM
Dinosaur
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Just a hint that I've found helpful over the years; instead of 'masking' tape try black vinyl electrical tape. It gives clean, crisp edges and if cut in narrow strips will form over and around compound curves much better than any paper based masking tape. I typically remove the tape shortly after spraying on the final color coat. Another hint is to sand the edges of the taped paint line with about 400 grit sandpaper after the paint dries and before a clear coat is applied. As for brand, I've found 3M electrical tape the best. Good luck.

Tom
Jul 10, 2019, 10:12 PM
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I saw the 3m vinyl masking tape at the auto paint store in different thicknesses just for that purpose and thought about getting some. Maybe I will give it a try, they also had rice paper masking tape among other types. It’s a whole different world in the paint store, so much specialized stuff and I have no idea what it all does.
Jul 11, 2019, 11:05 PM
Scott
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If you plan on masking around curves get a roll of fine line tape. It is kind of green and comes in various widths. I usually use 1/4". It is similar to electrical tape in that it is vinyl, but is made for paint. It will stretch to go around corners smoothly and masking tape will stick to it to mask off large areas. As already mentioned, pull all the tape shortly after spraying to soften the edges. Lightly scuff and clear for a smooth transition.

Scott
Jul 11, 2019, 11:55 PM
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Thanks for the tips.
Jul 12, 2019, 10:37 AM
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I shot some primer last night using Rustoleum spray primer and will sand it out after work. It is powdery to the touch, but I think its supposed to be that way as its a filler primer and will sand off to fill low spots, then I will putty the holes and low spots, clean, primer again, sand and repeat until smooth. I’m new at this so it’s a learning experience.
Jul 12, 2019, 01:00 PM
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Quote:
Originally Posted by nhk750
I am trying to get better at painting and need some simple advise. I am going to paint a fiberglass Specialties cowl and wheel pants and am using Rustoleum spray paint. So far I know to sand down with 220 grit before primer coat and 320 between color coats and use wax and grease remover solvent after sanding between coats and clean with a microfiber cloth and tack cloth, but here's my questions.

1. How long can I leave the 3m low tack blue masking tape on (60 day release)? Do I need to remove it between coats of paint and reapply or can I just leave it on until done with that side of the color?

2. After I get done painting both colors, can I do my final 600 grit sanding over both colors at once or do I need to sand up to the color separation lines carefully before clear coating? Can I just sand lightly over the paint without worrying about the colors running into each other?
When I paint I will put down one base coat with no masking tape (usually white). Let that cure real good before trying to mask off other colors. Sand lightly with 320 wet paper with 2 drops of dawn dishwashing liquid in it. Wipe dry with a paper towel. Wipe clean with a cotton towel wetted with lacquer thinner then swipe LIGHTLY with a tack cloth.

Now you are ready for masking. Use 3M 218 fine line masking tape for your actual trim lines. Back that up with blue masking tape and any kind of paper (I like the masking tape/paper dispenser you can get from lowes). After masking, wipe lightly again with the lacquer thinner then barely with a tack cloth. Shoot your color, clean your gun/airbrush, then remove the tape. Don't leave the tape on. And when you shoot the paint, fog it on at the tape lines. The less the better.

After you have masked and shot all your colors, wait a week or so before sanding. I don't know what's going to happen with Rustoleum when you sand one color into the next. I suspect it will be ok. We're talking lick and a promise sanding at this point anyway. Don't get happy with it. You might even run a real light fingernail over the color lines to get rid of any ridges first.

Good luck and post some pics up of the finished product

carl
Jul 13, 2019, 11:37 PM
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Thanks for the tips, I did get some 3M #471 vinyl masking tape at the auto paint store. They said it works great for curves and such.
Jul 17, 2019, 01:00 PM
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Ready for color coats


I prepped all the parts, primed with automotive primer, filled with Evercoat spot filler, sanded, repeated, then shot a coat of white primer, now the parts look great and ready for color coats. Will sand with 320 before the color coats, then some 600 before the final clear. I'm using Rustoleum for everything and wax and grease remover between coats to clean after sanding.
Jul 26, 2019, 07:44 PM
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Finally got the blue painted on the cowl today. It came out great with a tiny bit of orange peal, but from a foot or two away looks perfect. The shade of blue is a tick darker than the Ultracote, but I can live with it and my wife says it’s a good match so I’m happy.

Wheel pants and gear came out good too.

I dint think I will shoot a clear coat as I have heard mixed reviews about Rustoleum clear yellowing in the sun and lots of guys say the paint will last fine without clear.


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