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#### Rancho5

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Getting about time to respray my Goo rolled screen with Cream and Sugar. I bought the following spray guns at Harbor Freight today.

This one is low pressure, low volume LPLV
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?function=Search

This one is ???
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?itemnumber=47016&Submit=Go

My compressor is 1 HP, 3 Gallon. 125psi, 2.4 SCFM @ 90psi/3.7 SCFM @ 40psi

There was a painter at Harbor Freight who helped me a little, but he thoroughly confused me with the math. Apparently when choosing a paint sprayer, it's not the AIR PRESSURE numbers that you need, it's also the VOLUME. When I mentioned that I thought I was advised to get a HPLV sprayer he said that didn't make sense since I was working indoors. He said the over spray would be too much for a small home theater.

So which is best for a screen and is the same one good for outside trim, garage door, etc?

#### Harpmaker

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This is the first I have heard of LVLP guns. Your link to the H.F. LVLP gun didn't work, but I think they only have one (http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92841). I will try to get one of these next time I go to H.F..

The key to figuring out if a gun will work with a specific compressor is to compare the maximum SCFM output of the compressor and the required SCFM input of the gun. It appears that, mathematically, your compressor isn't powerful enough for either of the guns you purchased.

Your compressor is rated 2.4 SCFM @ 90psi/3.7 SCFM @ 40psi, while the LVLP gun needs 5.5 to 9 SCFM @ 20 to 45 PSI and the HVLP needs 6 CFM @ 50-70 PSI.

The problem here is that SCFM (it stands for Standard Cubic Feet of air per Minute) is not really a standard reference, but can differ from one manufacturer to another. CFM (Cubic Feet of air per Minute) is another differing standard because there is no way of knowing if the compressor input or output is being referenced; with tools I would assume it's the air volume needed for proper use of the tool, but you never know these days.

If it were me, I would try the LVLP gun first and see how it works and how the finished test panel looks. Since it has a 2 mm tip it will spray larger droplets of paint than the HVLP gun with a 1.5 mm tip, but the 2 mm tip could work quite well.

Since you have both guns I would try the HVLP out as well. As long as you don't damage anything and keep all packaging, H.F. has a very good return policy.

Both Lowe's and Home Depot sell paint cheap that they have mismatched for color (something like \$5 a gallon). I would recommend getting some (color doesn't matter, but it should be relatively light to mimic your screen paint or primer) and practice spraying with that until you get familiar with how your spraying setup works and lays down paint.

As far as the painter at H.F. not understanding using an HVLP gun indoors, perhaps he never used one that way? Certainly it is best to spray anything outdoors, but I spray all my screen panels in an unventilated 20x24 foot shop with an 8 foot ceiling and any overspray or bounce-back I get from spraying with my HVLP gun is simply dust about 3 to 4 feet from where I am spraying. :huh: I also NEVER get any paint coming back on my clothing and since I spray with the gun about 12" from the screen I'm standing, at maximum, 2 to 2.5 feet from the screen while spraying it. While I'm sure I get paint dust on my clothing, it is not visible to the naked eye and comes out in the wash. I also wear glasses and have never had a problem with getting paint on them either (and very little dust).

Something else I almost forgot to mention is that neither of the guns you bought have an air gauge/regulator on them. I would recommend this so that you can have your compressor's regulator wide open and control the pressure at the gun. They aren't expensive.
http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=90590

#### mechman

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As Harp mentioned, your weak link is your compressor. And if you don't use it enough or need the extra cfm's, I'd just get a Wagner Control Spray. If you have use for a larger compressor then it would be fine. But it makes very little sense to spend hundreds on a new compressor when you can spend less than a hundred on the Wagner. :T

#### Rancho5

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We got the compressor to run a small nailer to do trim work, etc, and getting a larger one would be foolish for our needs. If it's too small to run either gun then you're saying get a Wagner Control Sprayer?

Can I do a screen with this type of sprayer?

#### Harpmaker

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We got the compressor to run a small nailer to do trim work, etc, and getting a larger one would be foolish for our needs. If it's too small to run either gun then you're saying get a Wagner Control Sprayer?
To be honest, getting the Wagner Control Spray would be the best bet. Your compressor might do to run the LVLP gun, but it's a long shot. Yeah, getting a larger compressor just to run a spray gun isn't cost effective at all.

Can I do a screen with this type of sprayer?
Absolutely! Mech will have to give you tips on using the Wagner since I don't have one. They are very good sprayers from what I have heard and read.

Here is a Google Products search on "Wagner HVLP sparyer":

Also found this add for the Wagner Control Spray Double Duty at Home Depot.

This sprayer seems to be the replacement for the older Wagner Control Spray, but it is more powerful while still being a HVLP unit. These have also been used very successfully to paint screens and would do an even better job at painting larger objects outside. Home Depot stores will match their internet price and I believe Lowe's (and perhaps other stores) will also price-match the HD sale price.

#### Rancho5

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Fantastic information! Thanks so much. I'm off next week (after vacation) to buy a paint gun.

#### mechman

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The Wagner is very simple to use and clean. The key thing to using it is to use the viscosity cup, included with the gun, to get your paint thinned properly.

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