Should I wait for color coat to "gas out" before spraying clear?

ChicknPickn

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I know this probably has been answered a couple dozen times here, but I'm not having any luck finding some basic answers.

I've sprayed the body with Duplicolor flake paint - - three coats as recommended, all good so far, no ugliness has appeared yet. Humidity, temp are all good.

Do I need to start the clear coats while the color is still curing? Or is it better to let it gas off a bit? For how long?

Would you go for more than three color coats, or leave a sleeping dog lie?
 

Sea Devil

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The one thing you must do is keep your clear coats light at first so that it doesn't make the flake lie down. That's super-crucial with metallics.
 

ChicknPickn

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The one thing you must do is keep your clear coats light at first so that it doesn't make the flake lie down. That's super-crucial with metallics.

Thank you for that tip! I knew there were special considerations with metallics, but wasn't sure what they were. So I take it that I should apply the very least amount per spray that would produce an even sheen? Maybe a couple of applications per day?
 

Sea Devil

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Don't worry about dry time, especially with really light coats. They pretty much dry on contact, but you can wait 10-20 minutes if you want. It will look like crap at first, kind of like 220 sandpaper. There will be thousands of tiny dots of paint, but hopefully no blobs. Whether you shoot with the body flat or vertical, do it from kind of far away -- maybe fourteen inches -- so that any potential blobs fall to the ground before they reach the body. You can use a shield (cardboard, newspaper) to catch any drops; they usually happen close to the can. Once you've built up enough thickness (maybe 3 coats of three passes each), you can start to lay the clear on wet enough to self-level a bit as it dries, but not enough to flood the surface. Again, dry time is not really an issue between coats, unless you've done what many amateurs do, and laid on way too much finish that dries on the surface and traps the solvents underneath a skin.

With flake finishes, you want lots of clear. A pro finish should not require any sanding, but you might need to sand. Make sure that there's enough clear that you won't sand through it, and you should be OK.

Final tips: warm the can in hot water from the faucet before spraying. Make sure the tip is clean. Every single time you put the can down and pick it up again, give it a quick test on some newspaper to make sure it's still working the way it was when you put it down. Every. Single. Time. Do not ever skip this step.
 
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ChicknPickn

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Don't worry about dry time, especially with really light coats. They pretty much dry on contact, but you can wait 10-20 minutes if you want. It will look like crap at first, kind of like 220 sandpaper. There will be thousands of tiny dots of paint, but hopefully no blobs. Whether you shoot with the body flat or vertical, do it from kind of far away -- maybe fourteen inches -- so that any potential blobs fall to the ground before they reach the body. You can use a shield (cardboard, newspaper) to catch any drops; they usually happen close to the can. Once you've built up enough thickness (maybe 3 coats of three passes each), you can start to lay the clear on wet enough to self-level a bit as it dries, but not enough to flood the surface. Again, dry time is not really an issue between coats, unless you've done what many amateurs do, and laid on way too much finish that dries on the surface and traps the solvents underneath a skin.

With flake finishes, you want lots of clear. A pro finish should not require any sanding, but you might need to sand. Make sure that there's enough clear that you won't sand through it, and you should be OK.

Final tips: warm the can in hot water from the faucet before spraying. Make sure the tip is clean. Every single time you put the can down and pick it up again, give it a quick test on some newspaper to make sure it's still working the way it was when you put it down. Every. Single. Time. Do not ever skip this step.

Man, thanks bigtime for these tips. I'm noticing that after several clear coats today, the surface, as you noted, isn't what I would have expected. It looks sort of satin, or even like super fine sandpaper. Not pimply, no blobs, but not a gleaming sheen like I might have expected. I get the feeling I'm going to have to wet sand before the final spray. You're spot on about checking the spray can nozzle. I came close to shooting a mess on an otherwise decent looking surface. Going on your advice, I think I may do more clear than I'd planned.
 

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Sea Devil

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One more tip: if sanding is required, and it probably will be, spend more time with the lower grits, and you won't end up with a glossy finish with lots of scratches. That's mostly 600 and 800 unless you have serious orange peel. If you do, be relentless in pursuing flatness! Start with 320 if you have to. Spray more clear if you think you're almost down to the color coat. The moment you hit it, it's too late! No orange peel? Start with 600 or 800. And use a block! (Not for round-overs, of course!)

Less is always more with lacquer, but metallics get there differently, and may require more removal of material along the way. Abrasives must never, ever contact the color coat, but flatness must always rule! Don't ever try to flatten lacquer by spraying more if you can avoid it. Tiny inconsistencies, maybe less than .002", can be smoothed on your last coat, but that's it.

'Acrylic lacquer"? No need for quotation marks. That's what it is.
 
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Sea Devil

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And, crudest explanation possible: if you have a defect, no matter how small, like the one above, it will never work without sanding it flat. The other one will probably flow out with a wet coat. There is a middle ground.

39A723EC-04DC-49EA-B6FD-2E416709D338.jpeg
 
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Sea Devil

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If you get a "blob" and try to sand it down right away, it may look like the top (cross-section/profile) image at first, and then turn into the bottom one. Be careful!
5EF9877D-6100-4E1D-BFD7-8B4A28055554.jpeg
 

stratisfied

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Some people have trouble with the can dripping onto their finish and so hang the body vertically and spray it. Unfortunately, this can create runs in the finish if you try to lay down a nice finish coat. You should switch nozzles if you are getting any dripping at all but many times, you get dripping because your finger placement on the spray nozzle overlaps enough for the tip of your finger be in the spray pattern. Sounds dumb I know, but with clear, it's not always obvious (paint on your finger tip).

If you do get a drip, leave it alone unless you have enough clear coats on it to wet sand it out without going through the clear. If it happens early on, you risk sanding through into your color and you should just leave it alone and continue to build up your clear coats until you are ready to wet sand and buff. You can wet sand the area level as a part of the finishing process and may find the defect has flowed out and disappeared after successive coats.

I always paint my bodies laid flat. I shoot the back first, let it dry and then flip it over and spray the front, blending the paint from the sides into the contour that rolls over to the back. It comes out the same as painting it all at once after buffing and it allows a heavier, self-leveling coat to be sprayed with any orange peel just flowing right out.
 

ChicknPickn

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Well, I have to say that working with a metallic turns out to be a real education. As Sea Devil emphasized, touching the color coat with an abrasive is a big mistake. I had a speck on the color coat and thought that giving it a little touch with 600 grit paper couldn't hurt anything. Wrong!! The blemish is small, and it's on the back of the body, but I can see it through the clear coat.

Fortunately, I'm treating this project as a learning experience and won't be crushed if it has a flaw or two, but this is very different from other finishes (lacquer over tinted shellac, solid color nitro, etc.) I've attempted. Also, I've learned that pine needs more grain filling and sealer than I'd thought. Everything looked smooth until the first color coat went on. Primarily on the sides. Live and learn.
 




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