Okay...I managed to get the initial coat on my 69 before taking a breather last week so you could say that now I have my feet wet.
Along with my wet feet I now have some more questions for you lacquer guys, especialy those that use it with HVLP guns. You see I seem to have had a heck of a time getting the lacquer on wet enough and I don't know why. I'm thinking that I was spraying it too fast because I didn't want it to run and have the metalics bunch up...no danger of that one!
The spraying was done at about 67F with about 70% humidity with a Devilbiss Plus(GFG-670) HVLP compliant gun set to about 32 psi at the gun and a 1.3 tip. I tried to set the fan as wide as possible which according to the Devilbiss specs is about 12". The lacquer was thinned to specs(1 part paint to 1-1/2 parts thinner) I then tried to set up the gun as per a procedure from the Southern Polyurethanes, Inc web site which basicaly has you turning out the fluid adjustment(after the fan width is set) from the closed position until it looks even in build. In contrast a Devilbiss bulletin(SB-2-001-F) says to turn the air cap so that the pattern is horizontal and then adjust the fluid so that the fluid is the same across the pattern as judged by the eveness of the runs. This second method has me thinking that it would produce a much wetter coat but that's just me and I might be wrong about that.
Anyways here are some of what I hope are basic questions that can be easily answered. Here goes......
The tech sheet says that drying time between coats should be 5-10 min but it was flashing off in LESS than a minute. Should the fresh paint be "wet looking" until it's in the 5-10 minute window? I'm using DTL876 thinner and it's good for 65-85 degrees and the day I sprayed it it was about 67 so that should have helped and made it flash closer to the 10 minute mark but it didn't. So my first question is how can I get the lacquer to stay wet longer? Is this a gun setting issue or am I spraying it wrong?
I thought that maybe I was moving too fast and that might be so but it only took one coat to cover the primer and I was told that it should take 2-3 coats so why would I have been able to cover the primer with only one coat especialy if I was moving too fast?
I think my quick flashing problems might be with the gun set up but at this time that is just a guess so any advice here would be great. I'm trying to do everything here by the book to eliminate any variables but one major problem it seems is finding good specs for spraying an old product(lacquer) with new technology(HVLP gun). The Devilbiss Plus product sheet doesn't list a tip size or air pressure for lacquer and the PPG sheet only says 10 psi at the cap for a pressure with lacquer and I can't measure that so I'm sort of throwing darts in the dark. The guns inlet pressure range is 30-40 psi so Im wondering if maybe I shouldn't drop the pressure to say 25 psi or so...just guessing that since lacquer is so thin that maybe it doesn't need the higher pressures....any thoughts on that one?
My last question is why do you sand between the coats of lacquer...is it to level the surface to prepare for the next coat or is it for adhesion? The way I understand it is lacquer dries(it doesn't cure) and that the top coat "melts" into the underlaying coat so it doesn't need sanding to "stick". This question is more for my curiosity than anything.
Well sorry for the long drawn out post but I wanted to get as much info as I could to try and make it easier to get some ideas. I don't mind playing and experimenting a bit with pressures and fluid setting to get the gun set up properly but at about $500 a gal and having to drive 7 hours round trip to get it I really don't want to waste it.
I'll look forward to your thoughts.

Along with my wet feet I now have some more questions for you lacquer guys, especialy those that use it with HVLP guns. You see I seem to have had a heck of a time getting the lacquer on wet enough and I don't know why. I'm thinking that I was spraying it too fast because I didn't want it to run and have the metalics bunch up...no danger of that one!
The spraying was done at about 67F with about 70% humidity with a Devilbiss Plus(GFG-670) HVLP compliant gun set to about 32 psi at the gun and a 1.3 tip. I tried to set the fan as wide as possible which according to the Devilbiss specs is about 12". The lacquer was thinned to specs(1 part paint to 1-1/2 parts thinner) I then tried to set up the gun as per a procedure from the Southern Polyurethanes, Inc web site which basicaly has you turning out the fluid adjustment(after the fan width is set) from the closed position until it looks even in build. In contrast a Devilbiss bulletin(SB-2-001-F) says to turn the air cap so that the pattern is horizontal and then adjust the fluid so that the fluid is the same across the pattern as judged by the eveness of the runs. This second method has me thinking that it would produce a much wetter coat but that's just me and I might be wrong about that.
Anyways here are some of what I hope are basic questions that can be easily answered. Here goes......
The tech sheet says that drying time between coats should be 5-10 min but it was flashing off in LESS than a minute. Should the fresh paint be "wet looking" until it's in the 5-10 minute window? I'm using DTL876 thinner and it's good for 65-85 degrees and the day I sprayed it it was about 67 so that should have helped and made it flash closer to the 10 minute mark but it didn't. So my first question is how can I get the lacquer to stay wet longer? Is this a gun setting issue or am I spraying it wrong?
I thought that maybe I was moving too fast and that might be so but it only took one coat to cover the primer and I was told that it should take 2-3 coats so why would I have been able to cover the primer with only one coat especialy if I was moving too fast?
I think my quick flashing problems might be with the gun set up but at this time that is just a guess so any advice here would be great. I'm trying to do everything here by the book to eliminate any variables but one major problem it seems is finding good specs for spraying an old product(lacquer) with new technology(HVLP gun). The Devilbiss Plus product sheet doesn't list a tip size or air pressure for lacquer and the PPG sheet only says 10 psi at the cap for a pressure with lacquer and I can't measure that so I'm sort of throwing darts in the dark. The guns inlet pressure range is 30-40 psi so Im wondering if maybe I shouldn't drop the pressure to say 25 psi or so...just guessing that since lacquer is so thin that maybe it doesn't need the higher pressures....any thoughts on that one?
My last question is why do you sand between the coats of lacquer...is it to level the surface to prepare for the next coat or is it for adhesion? The way I understand it is lacquer dries(it doesn't cure) and that the top coat "melts" into the underlaying coat so it doesn't need sanding to "stick". This question is more for my curiosity than anything.
Well sorry for the long drawn out post but I wanted to get as much info as I could to try and make it easier to get some ideas. I don't mind playing and experimenting a bit with pressures and fluid setting to get the gun set up properly but at about $500 a gal and having to drive 7 hours round trip to get it I really don't want to waste it.

I'll look forward to your thoughts.

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