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Old 07-09-2006, 12:06 PM
KNanthrup KNanthrup is offline
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Originally Posted by kenseth17
Acrylic enamel should spray glossy and remain glossy (unless a flattener were added to make it a semigloss or flat paint) It should add a little gloss with hardener added vs no hardener. You really should have a regulator at the gun. Run the pressure full on the tank guage, and after 25' or more of airline should be a moisture trap, and then regulate to spraying pressure at the gun. 3/8 airline should be fine with most conventional guns, but many hvlps need high flow fittings to spray right. Just make sure you are not losing too much airflow anywhere to the gun, like nothing restricting it. I am guessing maybe your pressure was too low at the gun if you have no idea what it is and the correct hardener used and right viscosity of the paint. Pick up a regulator to install at the gun. If your using a conventional gun your pressure should be somewhat high, probably somewhere around 50 psi at the gun, but start at paint man. recommendations and adjust from there till it sprays well. What it boils down to is the paint isn't atomizing. You want it to produce fine enough droplets that the surface with be smooth but not dry. You control this by tip selection, fluid flow, as well air pressure and your distance and speed spraying. Read some of brian martins (martinsr) basic of basics on gun adjustment, should be on this site if you do a search, as well as some other threads. Also southernpolyurethanes has an article on gun adjustment I believe. Most conventional guns the needle size in them should spray enamel okay. Any idea of the tip size you have and what gun are you using?

Thanks so much for your help. I am using an HVLP gravity feed gun. The tip is a 1.4mm, but I don't really know what that number means in terms of what it does to the paint and if it is correct for what i am doing. I guess i should get a regulator at the gun but it's Sunday and everything is closed, so I may do a little more experimenting. I don't know how much air pressure loss would occur through my line but i think i might try turning it up even a little more. Any idea what happens if I go past the max amount for the gun?

I don't know, I guess it's my fault for lack of equipment and technique prep but it's just been very frustrating for me to come to such a basic vital problem after 50+ hours of body work and prep and I can't even get a basic coat on paint shot. Ahhh!
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