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Thu Apr 28, 2011 7:32 am

hi, im about to paint my car 2stage urethane . how much viscosity for for this kind of sprayer should be? as oh! my spray gun is harborfrieght hvlp turbine.

thanks

Thu Apr 28, 2011 8:18 pm

I don't know, but post pics when you are done! I am thinking about buying a high end turbine system.

Here is a ton of cut and pasted info I have collected on the subject. Each Paragraph is from a different online source!!

"
Accuspray's gravity gun with various nozzles and tips. As long as I use reducer of at least 15% the paint goes on well and only needs a little work with a 1500 Clear Coat disc before going to 3000 Trizact. I use PPG Concept.

Dustin, what Accuspray wont tell you is that that turbine super-heats the air going through the nozzle and tip.... you have to way-over compensate for that withyour reducer selection. Go with a 100 degree reducer if it's 80 degrees in the room. Practice with this and let us know what you find. Turbine systems are great technology, but use a different learning curve than figuring out a pneumatic system. Less contamination, much higher temperatures in your air delivery....

you have to use about 25% more reducer.

I needed to reduce my paint even further than what Diamont calls for. He also said, I need to use a SLOWER reducer. I am used to using a medium reducer, but he said NO, use the slowest you can get.

We adjusted for the turbine's warm air by using the paint manufacturer's recommendation for high-temperature (75-90 degree) reducer. This worked fine and the two-part, single-stage urethane paint (PPG DCC) applied nicely, and buffed out beautifully and easily.

I had never used a traditional spray system, so I had no problem holding the HVLP gun as close to the surface as is recommended. My friend, who had always used compressed-air standard-guns and HVLP-guns, had to get used to holding the HVLP turbine gun close to the surface (6"-8"). Until he got the distance right, his applications had significant orange-peeling.

I am just getting aquainted with a 3 stage GRACO turbine HVLP spray unit. Once you get the hang of them - they are GREAT! The air from the turbine is heated so the gun handle gets quite warm. The atomization of the paint is unbelievable. I am practicing by painting an old Jetta for starters. Here is what I have found so far:

1) The HVLP lays down a coat that is smooth as glass - no problem. HOWEVER - get any speck of dust in the air and you will see it in the finish. A dustfree spray area is a MUST.
2) The HVLP laydown is so smooth - ANY imperfection in the body work will be magnified. Sanding with 400 grit paper, washing with paint prep and finishing with a tack rag MUST BE DONE. To that end - more attention to prep body work, priming and sanding must be done to get the proper finish.
So far the HVLP Turbine unit is much easier to use than the old spray guns and there is very little paint in the air from spraying. My automotive paint supplier used to sell me 1 gallon of paint to paint a Jetta with the old style regular guns. Two quarts of paint will do the same Jetta with the HVLP without even trying to be cheap with the laydown. 70%-90% of the paint goes on the car as opposed to 30%-40% with the regular air spray gun.

usually spray with a capspray cs8100 but have also used the new titan 6 stage units. Based on my expierence with theese i can say without a doubt how imperative it is to properly thin the paint. From what i have seen, thinning/reducing 20% makes the paint go on very evenly with minimal orange peel. The manufacturer suggests 10% but they are assuming your using a traditional compressor. "