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Old 01-07-2005, 03:18 PM
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OK, what did I do wrong

I primed the panels with 2K primer

Wet sanded 320, then 400.

Wiped immediatly prior to spraying with prep-solv, then a dry clean cloth, then a tack rag.

Paint is Dupont Centari single stage
Color Black

I sprayed a light coat, waited 15mins until it tacked up, then a second, third and a final coat. ~20mins between coats, until tacky. Everything apperaed to be fine until the final coat, when on one panel BIG fisheyes appeared.
I discontinued spraying. For the next 10 minutes, everything on the other panel appeared to be fine. Then tiny fisheyes EVERYWHERE.

I've only painted the windshield pillars and removable roof. I think the fisheyes in the roof are small enough that I can buff everything clean, but heaven forbid this happen on the entire car...with RED paint

Someone please shed some light on this. So far, my first paint project has gone just about every way wrong that it could.
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Old 01-07-2005, 03:33 PM
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You have picked up contamination from somewhere. Since you wiped it down with a solvent that should have gotten rid of silicone, etc., assuming your wipe-down rags were really clean. That fact combined with the description of a bunch of pops showing up later sounds to me like you have water contamination in your air lines. If that's the case and the water is atomized well in the paint gun, the damage will be as you described.

One suggestion - don't wet sand the primer. Dry block sanding with a guide coat 'til it is perfectly smooth is preferred because the primer is porous and can absorb water. Also, 320 and 400 was a little overkill. I use 320 for BC/CC but you may want to use 400 w/ one step. Anyway, these grits are so close together that one or the other is fine, especially if you plan to polish. ALWAYS use hardener.

Last edited by willys36@aol.com; 01-07-2005 at 03:42 PM.
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Old 01-07-2005, 03:42 PM
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How long did you wait after wet sanding before painting? When you used the prep-sol did you wipe it off before it dried? I am not familiar with the product but with PPG acryl-a-clean you have to wipe it off before it dries. Do you live somewhere cold? Did you have a kerosene heater running before you painted? Give us all the information you can.
Jeffrey
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Old 01-07-2005, 03:50 PM
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I live in FL. Was ~72 degress today, so no heater.

I wiped with prep-solv, then, after it dried, wiped again with a clean white rag, then after that I wiped it with a brand new tack rag.

I did use hardener in the paint. Water in the lines is possible I suppose. There is a water trap on the compressor, but I doubt that it's something "high grade"

I have the option of renting a booth next week, for around 100$. Would be a downdraft booth, dry air, etc... Might be a better option for me. I'm not sure what a good water trap would cost??
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Old 01-07-2005, 03:58 PM
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Cool

as willys 36 said you most likely have water in your air lines so get yourself an inline filter and get a disposable nappy pull out the obsorbent material and put in the filter and no more water
hope this helps good luck chris
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Old 01-07-2005, 04:41 PM
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These work pretty well when used with one of these mini in-line filters @ the gun. These two in series will do a good job of eliminating the water and oil carryover from your compressor unless you live in Houston where the humidity is 100% all summer long! That mini filter is available at Harbor Freight stores (not on their web site) or at paint stores and costs less than $15.

That wall mounted unit is great for doing a preliminary pressure setting for the gun too.
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Old 01-07-2005, 06:34 PM
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Ocasionally I get the same problem not from wax or water or other contaminents. Simply from too wet of coats and not enough dry times between coats. I now that because the fisheyes are on the horizontal panels only. Black is very slow drying paint. It may have something to do with the humidity here in Florida slowing down the dry times. I live over in Lake City. I shot a blazer yesterday and the roof did the same thing a little. Small little fisheyes that will will buff out.
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Old 01-07-2005, 07:06 PM
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I'll check those things out tomorrow. I'm using a gravity fed gun, with Mac Tools stamped down the side of it. Unsure how good of a gun it is, but it was spraying fine until the fisheye problem mentioned above.

The weird thing was the LARGE fisheyes on the window pillars. Once I saw those I stopped. Only 10 minutes later, very small ones began to appear on the roof. (Miata, hard-top is removable). I understand the smaller spots on the roof being water perhaps, but what do you thing the LARGE ones were on the pillars? Just too much paint perhaps?

I'm such an amateur that I'm not sure a high quality gun would make that much difference.

OBVIOUSLY, this isn't for a show car! It's for a race car, but I do take pride in my work, and I'd like it to look the best it can given my abilities and the paint I used. This is teaching me quite a bit about bodywork and painting. I'm not sure I'll travel down this road again in the future, but perhaps after this is all done, I will at least have a better understanding and respect for those that do paint.
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Old 01-07-2005, 10:27 PM
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Well, here I go again being the odd man out. I have to disagree with the water explaination. Water in the line gives you...well.. water in the paint, NOT "fisheyes".

It sounds like you applied some pretty "Light" coats at first. Of course one mans "Light coat" is another mans "bomber coat" so it is hard to tell just how heavy the paint was applied. First let's start at the large "fisheyes", they are on the windshield posts huh? Well, silicones and similar products are commonly used on the windshield, along with the rubber running up the post on your Miata. There could have been something left on the surface. EVENTHOUGH you cleaned it, it could have been sanded INTO the surface from before for example.

"Fisheyes" are caused by a contaminant ON the surface that the paint can't stick to. The paint doesn't have enough "surface tension" to form a layer over it, so it "falls" off the contaminant leaving the little "crater" or "fisheye".

Applying the paint in a light coat "can" cover a contaminant. The lighter coat dries as it hits the surface and creates sort of a shell. You could have applied the two light coats and followed with a wetter coat that re-wet the first two and caused it to loose the surface tension created by the dry spray. That is VERY common, for fisheyes to show up after a wet coat like that. PLUS, you are talking about a windshield post, it is hard for a seasoned pro to apply a "normal" coat on something as small as that, applying the paint too wet is easy to do.

Another thing, if these fisheyes only showed up in one area, how could it be water in the air, it would then be all over.

The tiny fisheyes "EVERYWHERE" sound like solvent pop to me. "Fisheyes" don't appear ten minutes later, they appear immediately when the paint can't stick to the contaminant. The solvent pop appear a few minutes later as the excess solvent in the film pushes it's way up to the top.

It sounds like you need to speed up the gun travel, or "tune" your gun better (read the FAQ post above on atomization) or use a slower reducer to allow it to stay "open" longer.

By the way, applying too much paint too fast is common on something like that removeable hard top as well. There is no way to get a run right? So it is human nature to apply it a little wetter.
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Old 01-07-2005, 10:49 PM
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MS, is right on the money but one other thing I would question that goes along with what MS said is, its been years since sprayed any centari but last I remember it was a two coat paint.
Those added coats could very well be the problem with the solvent.
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Old 01-08-2005, 12:24 AM
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That's what I meant to say!
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Old 01-08-2005, 06:43 AM
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agree with martinsr

bet there was silicone caulk used on the pillar to seal a leak and now it's sanded into the steel.

only cure I know is sandblast the hell out of it

another cause of fish eyes is if you are painting in an area where cars were buffed or waxed recently...need to clean the room more.

I would go rent the booth, better everything
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Old 01-08-2005, 07:21 AM
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ok, so what I'm getting out of this are:

I sprayed to MUCH paint
The last coat being the wet coat is NOT correct, at least after having a previous 3 decent coats.

I had contaminents on the windshield pillar.

I didn't use "ideal" paint.

Well, the last one I can't change, I'm stuck with the paint, as I've already had a gallon mixed up. I can't really afford to toss out $130.

The windsheild pillar was looking really good until I hit it with that last wet coat. Apparently next time I'll stop before that one.

I need to only apply 2 or 3 coats. I'm not sure about the tecnique though. Do I apply a light tack coat first for color, and then come back and lay some paint on or what?

I'm just trying to understand what I've done wrong, so I can correct it and/or prevent it from happening again.

I "THINK" I can wetsand/buff out the problems on the top. Unsure about the pillar though, the problems on there look like they went into the first layers of paint.

Last edited by Cracker Red; 01-08-2005 at 07:30 AM.
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Old 01-08-2005, 07:31 AM
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I need to only apply 2 or 3 coats. I'm not sure about the tecnique though. Do I apply a light tack coat first for color, and then come back and lay some paint on or what? [/B][/QUOTE]

+++++++++++++++++++++++++++++++++++++++++
Two wet coats will do you fine. For re-coat areas or in paint conditions that are not perfect, what painters will do with enamel
is spray a fast light cover coat and let it set 10-20 minutes than
spray two wet coats. The first coat will help avoid any reaction problems and kinda work as a sealer coat.

If a panel looks good after the first wet coat since you are re-coating don't use a second coat at this point.
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Old 01-08-2005, 08:24 AM
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sounds good Barry. I think the small ones will wet sand/buff out on the roof, but I'm unsure on the pillar.

What you are saying is to wet sand the pillar smooth again, and hit it with a light tack or "sealer" coat, and then one wet one. If it looks good after that, I'll stop.

DAMN there is a lot to learn here I had no idea that applying too much paint (too many coats) would cause fisheyes, but I think I'm getting it now. The solvents are trying to escape from the lower coast, but can't because of the middle or top coats have already begun to flash or dry. This causes the fisheyes?
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