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Old 05-15-2012, 11:45 AM
ecs ecs is offline
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Viscosity questions

First off, I've seen about a hundred threads of guys rolling rustoleum on their cars. No, this isn't what my thread is about. I'm using a sprayer, but still, the rustoleum is not going on the car. I decided to break out my electric "HVLP" (should be called LVLP) sprayer to see if it did anything other than spray bullets since I never used it before. I picked up a quart of black gloss rustoleum and a quart of acetone to thin it out. I have scrap metal and a trashed front bumper from a 1995 Cirrus to practice on. I just wanted to know if the sprayer had what it takes to atomize the paint. After an hour or two of fiddling around with the thinners (20% was too thick, even 30% was too thick, 50:50 acetone to paint did the best) and the flow setting on the gun, and I think I started to make progress. I got the paint to lay on with minimal orange peel and no runs.

I'm starting to think that this gun won't be able to lay down a decent finish unless the paint is thinned out enough. Which leads me to this question: Do you think that automative urethane (either SS or 2k) paint is less viscious than the rustoleum enamel paint? If so, I think I might try to spray the auto paint out of my "turbine" sprayer. I feel like the orange peel effect is coming from the reducers (acetone in my recent case) evaporating from the surface and leaving pits, hence the orange peel. It's just a theory, as I'm just a beginner in terms of painting; but I've done quite a bit of reading and research.

Don't worry, the scrap pieces will take the punishment of testing any kind of paint before it goes on my car.

Also, a sidenote. Even after leaving a piece of exhaust pipe covered in the black rustoleum paint out in the sun with temperatures ranging from 70-80 degrees for a week, the paint still hasn't cured. I'm able to make an indentation in the paint without much pressure. That's one of the big reasons why I won't and refuse to use enamel on my car. It takes far too long to cure, and for a daily driver, the stone chips/salt rocks will DESTROY the paint before it even gets a chance to cure. It was a great test though to see how the sprayer laid down the paint.

And drumroll... here's the sprayer I used.

I know, many of you are cringing at it, but being honest, it didn't do a bad job as far as I can tell and there was a VERY minimal amount of overspray. Then again I've never sprayed with a compressor+hvlp setup so comparing the two isn't my place. I just tried to get it to work by adjusting how thin the material was (since it has no air adjustment setting) and adjusting the flow output. It takes time, but then again I don't know any spray system that you can just pick up and go. All of them require some fine tuning IMO.

Additionally, the air output NEVER got any warmer. It stayed almost exactly the same as the ambient air, if not cooler somehow. I know a lot of guys are saying that turbine systems warm the air. Mine didn't. Might be because I don't have the huge box 4 stage turbines that they do.

I didn't want to post pictures since the majority of the ones I've seen with rustoleum paint jobs look nice through a lens, but at the perfect angle or in person, you can see MASSIVE blemishes. I didn't encounter any significant blemishes other than orange peel but I doubt I'll be able to get the orange peel to show the same in the photos as they are in person. If anyone wants to see them, just ask.
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