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iceNine · 05-13-2009, 01:18 PM

OK about sprayers and paint application:

So you have a compressor and an appropriate quality paint sprayer for automotive applications. I'd recommend an HVLP (high volume low pressure) sprayer as they give better results with less overspray and overall use less paint to cover the same area (good automotive paint is expensive).

Well, about the compressor; the air that is supplied by the compressor must be CLEAN and DRY. So an oil based compressor is a problem. You will need some pretty good inline filters to even hope to remove the oil that is bled off into the air stream. As to an oil-less compressor this is better but some people use inline oilers for their regular air tools so even if you remove that from the system the air hose has been contaminated by oil and will still shed off oil into the air that will mix with the paint spray and make it not stick well. Even if you just aid oil directly to your tools it can run back into the line and come out again when you spray paint. So buy a separate air hose for painting and never use that hose for regular air tools.

Removing water from the compressed air is also a big problem. There are a lot of inline filters that claim to remove water vapor but in my experience they only filter large droplets and the more atomized water is allowed through. You really need to add a drying cartridge filter inline with the regular filter to make the air really dry. This filter has a dessicant that absorbs water vapor from the air and when it is staturated it turns color and you throw it away and put more in (or dry it out in a hot oven if you are really a cheapskate). If you don't do these things the paint will go on contaminated with oil or water and no matter how good your spray technique is the job will never look great.

05-13-2009, 01:18 PM	#15 (permalink)
iceNine Some Skills Join Date: Jan 2009 Location: Maryland USA Posts: 61 Thanks: 0 Thanked 1 Time in 1 Post iTrader Rating: (0/0% )	OK about sprayers and paint application: So you have a compressor and an appropriate quality paint sprayer for automotive applications. I'd recommend an HVLP (high volume low pressure) sprayer as they give better results with less overspray and overall use less paint to cover the same area (good automotive paint is expensive). Well, about the compressor; the air that is supplied by the compressor must be CLEAN and DRY. So an oil based compressor is a problem. You will need some pretty good inline filters to even hope to remove the oil that is bled off into the air stream. As to an oil-less compressor this is better but some people use inline oilers for their regular air tools so even if you remove that from the system the air hose has been contaminated by oil and will still shed off oil into the air that will mix with the paint spray and make it not stick well. Even if you just aid oil directly to your tools it can run back into the line and come out again when you spray paint. So buy a separate air hose for painting and never use that hose for regular air tools. Removing water from the compressed air is also a big problem. There are a lot of inline filters that claim to remove water vapor but in my experience they only filter large droplets and the more atomized water is allowed through. You really need to add a drying cartridge filter inline with the regular filter to make the air really dry. This filter has a dessicant that absorbs water vapor from the air and when it is staturated it turns color and you throw it away and put more in (or dry it out in a hot oven if you are really a cheapskate). If you don't do these things the paint will go on contaminated with oil or water and no matter how good your spray technique is the job will never look great.