I have had this problem with a Rustoleum Gloss Black, but not this severe. It would spit a chunk at random onto a beautifully prepped surface. Then another...then another...etc. Sometimes two or three would come out at the same time.
I tried turning the can upside-down and clearing the nozzle, and this helped somewhat.
So, I pulled the nozzle off the can and tried to clean out that area of the can itself. I got a lot of dried crud out of there, and this action helped even more. I was actually able to get a good coat.
But the paint seemed to 'collect' under the nozzle, and I had to clean it out after every use.

My guess is that quality control on these things is less than optimal...duh, right?

I never had this trouble with the old Krylon. I should order a case of the 'industrial' Krylon and quit b***ching, I guess.

Allen

The only time I have seen pigment spatter in chunks that bad is when the paint has been frozen and basically ruined or when using paint that was not strained properly and put into a spray gun with the nozzle set too coarse.
The only recourse for a rattle can that does this is to return the can and buy from a more reputable source.
I will mention that I have NEVER had this happen with any "Hobby Store" paint brands/types such as Pactra, Testors, Perfect, Sig, Lustrekote, etc. or from Automotive paints either; it has only happened with "Hardware Store" brands like Krylon, Rust-Oleum, Valspar, XO-rust, and other "store brands".
I have had some really good results with Hardware brands too, but it is more of a gamble than my Airbrush with Aero Gloss/Brodak/Sig dope or Hobby Shop spray cans.

Allen-
You should NOT have to order a freakin CASE of some supposed "industrial" paint just to get decent quality paint. That is a load of crap most likely caused by some BS gubmint agency mamby-pamby VOC rules.

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Just to answer some of the questions here.

The paint was brand new and I was painting on the exact same primered surface in both cases. Out of 4 cans that I purchased 2 of the 4 cans were "this bad" another was spitting very badly but not spraying this chunky mess everywhere and one seemed fine.

I did not let the mess cure. After I shot the photo I immediately stripped everything off down to the bare tube, sanded, and re-primered.

Today I went and got a can of plain Krylon Gloss White and it went on beautifully! No spit no spatter. So now at least my Little Joe II and Lil' Herc have FINALLY got a decent coat of paint on them. I'll let the paint fully cure for a few days, wetsand and apply a final coat.

One thing I didn't mention was that you could hear a signigicant difference in the sound of the spray when the defective cans were spitting that garbage out. I will be exchanging them for more Krylon.

Don

I don't know if this applies in your particular instance, be prior to every application of spray paint, I make sure to shake the can well. Regardless of what the instructions on the label say, I vigorously shake the can for two full minutes (timed with my watch) after I start hearing the balls rattle inside.

Some people suggest setting the can in a bowl of warm water for a few minutes, too. Whenever I have done that it made the paint very thin and runny, though, so I don't recommend it.

Also make sure that you have thoroughly wiped down the surface to remove any dust and grit from sanding it. I wipe the rocket down again immediately before applying the paint.

Finally, apply the paint in steady, even strokes. Don't jiggle the can all around while you are spraying, because that will always lead to an uneven, pebbly coat. I don't know if that happened in your case, but it reliably produces such a coat whenever I do it. I can absolutely count on it. Apply spray paint in one smooth sweep (in one direction only) from one end of the rocket to the other. Start spraying just ahead of one end, and then sweep your arm (and the spray) down the entire length in a steady, smooth motion, keeping it the same distance away from the surface all the way, and don't stop until you have gone past the other end. Rotate the rocket a quarter of a turn or so, and do the same thing again. Repeat until you have covered the surface once, and then stop. Wait a minute or so, and then repeat the process one more time. In the interval between these applications, I keep rotating the rocket slowly, rotisserie-style, to insure that the paint doesn't collect on the downward side while it's still wet and a little bit loose. If the coat is still very thin, you can repeat the process a third time, but think carefully before deciding to do that. The result equals one coat of paint or primer. Wait for that coat to set up well (follow the recoat times stated on the label) before repeating the whole process again for a second coat, if needed.

I don't know if any of this contributed to the problem in your case, but I always get chunky paint spattering if (1) I don't mix up the paint by shaking the can thoroughly beforehand, and (2) if I shake and jiggle the can while I am spraying. The nozzle needs to have a steady draw from the can in order to put out an even spray. If the can is agitated during the process, it creates spikes and dips in pressure, causing sudden surges and drop-offs in the amount of paint that is being sent through the nozzle. The nozzle should also always be cleared after each paint session, and then checked again for clearing with a quick test spray before starting another one.

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The major constituents in a can of spray paint can separate into layers, with the heaviest one, the pigment, settling to the bottom and condensing while the can sits on the shelf. You need to thoroughly shake the can to allow the balls inside to mix the paint back up and allow the solvents to break up the condensed pigment and create a homogeneous mixture of the pigment and carrier. That's why I give the can a good two minutes of continuous vigorous shaking once the balls start rattling before I start spraying. If you don't hear balls rattling, it means that they are actually embedded in the condensed layer of pigment at the bottom of the can. They can't even begin to do their job of mixing up the paint until they start moving freely when you shake the can, so that's when I start to time the shake-mixing. And like I said, give it two full minutes of shake-mixing after that. When you are busy shaking the can, two minutes is a lot longer than you think it is, so you need to actually time it to insure that you have done it for long enough.

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SAM # 0011

I agree. My father went even further, insisting on shaking a spray paint can for a full five minutes after the metal mixer balls could be heard, then briefly test-spraying a piece of scrap wood or paper (or a tree stump, if outside) to make sure there were no solid chunks and that the spray can had sufficient pressure to do its job. After each painting session (unless a can's contents were exhausted), he would hold each can upside down and briefly spray it until no more paint came out, in order to clean residual paint from the nozzle. Using these techniques, I've never had "chunky" or "orange peel" paint coats with any brand of either enamel or lacquer spray paint.

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I have been out of this for a bit, but I used to do a lot of spray painting.... the ultimate fix is to get yourself and airbrush, kind of expensive though. I always found that if you drawn some warm water in a sink, and let your spray cans set in the warm water for about 5 minutes or so, that will get rid of that "orange peel" effect that I saw in your pics. Also, if you can spray indoors, that helps a lot too. Hope my little tip helps. Keep 'em flyin'!

Respectfully,
Gunner

I sure miss old Krylon

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Paul
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I too started having problems with my Rustoleum can of gloss black. At first it sprayed out very nicely. All i used it for was to paint some nose cones. Now Im trying to paint a body tube and i noticed that the nozzle is hard to press and paint is oozing out under the nozzle cap.... I never had this issue before with any can of rustoluem or krylon until now. My krylon is fine and so are my other cans of rustoleum. Just the black one is like this...

The nozzles on most cans (Rustoleum or Krylon) are notorius to plug up. The manner in which most of us use the product appears to be counter the intended use - that is to spray the can to vitual exhaustion in a single sitting. The newer high volume nozzle on the Krylon cans is even worse - the paint almost comes out like a hose!

There are four key issues to spraying with a self contained propellant: temperature, humidity, nozzle, and distance. All of these will have impact upon the quality of finishe due to the state of the paint when it strikes the surface. To hot, too dry, too far away and the paint will almost skin as a droplet. Too wet, too close, too cold, and the propellant does not have the time or energy to create a uniform mist. There have been discussions in the past about Winter painting and stepping outside, or under the deck if it is raining. As has been observed, painting with this is almost a crapshoot.

There are tricks to maintain some consistency in the paint delivery. Standing the can in a bucket of hot water prior to use. Really shaking the can prior to and during use - and I mean shaking like it is a maraca. Start to spray before the article and then continue past the end. That way the aerosol should be fully developed and even - no spitting at the base and nose. Try and put an even single coat in one sitting and then leave it in a warm place for 36 hours. Prior to using the paint make sure that the paint and the article have been in the same room and maintain some level of equilibration of temperature.

One other thing, and MarkB mentioned this, the nozzle of the paint can is the pressure relase valve which enables the propellant to drive the pigment and carrier from the pressurized container. There is a pick-up tube from the ball valve down the center of the can which is where paint is actually passed up to the spray nozzle (hence inverting the can to clear the nozzle with pure propellant). If you do not shake the heck out of the can there will be small lumps that will either be drawn into the pick-up and either plug or spit. One tiny little plug holds back the paint flow for a millisecond or two and the pressure will spit proportiuonally more paint to clear it.

As for the unfortunate results which you received I have no sure answer. It is absolutely not an orange peel. That is caused by the application of a second coat on top of a coat which has not dried. As the top coat contracts it draws the undercoat with it. It does look an awful lot like textured paint, or there was a nick in the nozzle that really blew up the aerosol. Possibly there is something on the first coat that reacted with the second coat and produced the BBs on the surface. I also would go with jeffyjeep on the use of matte and semi-gloss paints for base coats even over primer. Very light and frequent coats of matte paint will develop the coverage needed and provide a great base for gloss coloured pigments. Most of my yellows are actually matte white enamels with a couple of thin coats of yellow Tamiya lacquer.

I have had some success with Krylon C/S in getting a bagful of nozzles so I pitch the offending article at the first sign of problem, but even that is almost no guarantee. Paint will dry under the nozzle between the slits in the nozzle tube and that is were the crud starts tro build up. The best way? Procure the true industrial Krylon while you still may - the old original five balls that you can recoat in an hour or so. Cal VOC basically required that the consumer formulations can be breathed on directly. I swear I once read a State EPA position that aerosol paints should be able to be inhaled directly!

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