I am building a 10, and wanted to paint as I go. I also am trying to get away with painting outside (no booth) with just a 3m respirator. I painted my mustang years ago, did the priming outside and ended up renting a booth. It turned out nice, mostly due to prepping the primer well and wetsanding the finish. Painting outside, I expect to get some bugs and dust but plan on wetsanding either way.
Anyways, I wanted waterborne to reduce the VOCs, I also wanted single stage for simplicity of repairs and doing a little at a time. I am not painting a show plane, I want it to look decent and hold up. I ended up picking Stewart.
Last paint I used was traditional BC/CC sherwin (not waterborne). It was a learning process, but came pretty quick. Stewart does not lay down like what I have used in the past. The primer nor the topcoat. The primer is more difficult to spray well than traditional BC/CC topcoats, at least in my experience; and the Stewart topcoat is even more difficult than their primer. However, neither take a PhD in painting, just some practice. Watch the videos numerous times, really think about what they are saying, and what to expect.
I would recommend the finishline gun, as I found known settings; this helped. Use a paddle in a drill to stir, don't shake the can.
My first attempt at spraying primer, I ended up with a really rough spotty finish. I prepped the metal according to them, but didn't spray according to them. I sprayed just like the AZKO I started with. Just tired to lay it down. Next time I did what they recommend, fog or tack coat, then laid down paint. Much better, however I tended to make more runs than desirable. What I ended up figuring out later was I needed to adjust the needle. I had the needle wide open and used distance from panel and speed of gun to regulate the spray onto the metal. This sort of worked, and I had good result sometimes; usually ended up with runs.
Top coats. I was really excited to spray the top coat, I start with some small panels and emp fairing. Well again the needle was full open. Results were horrible, ran like a race horse. When the white top coat runs it tends to bubble and the bubbles seem to propagate back to the primer. The bubbles are tiny, almost looks like intense solvent pop (and I think this is what it is). These runs are almost always not repairable, you end up sanding past the coat into the primer to get rid of the bubbles. So several re-attempts, still using my technique of speed and distance to regulate spray amount; never really worked. Finally, I did some googles and realized folks were starting with the needle almost all the way in, and backing it out a little at a time for each fog coat and final wet coat. I don't remember seeing this in the videos, and don't really remember doing this when I painted BC/CC; but I was at a rented booth and had help (they might have done this). Anyways, what I found was start at 3/4 needle out, move up 1/8 of a turn each coat to end up at 1&1/8 out for the 4th and final coat (wet coat). These settings seem to work really well for me, no runs doing this. I think I could maybe go 1&1/4; but no runs after a week of sanding off runs and multiple attempts makes me happy. Another important thing I found was the previous coat needs to be tacky but no longer transfer paint when touched. This was something on the video I ignored and just timed about 5-10 minutes. Some coats have taken up to 30 minutes to not transfer paint, 5-10 minutes doesn't work. I have used these things I've learned and the primer sprays well too now. I usually only do two fog coats, and open the gun a little more; also the fog coats dry quickly (no paint transfer to touch) compared to the top coats.
Bottom line, must do light coats building up to a wet coat, coats must be tacky but not transfer paint, and start gun at 3/4 needle out and adjust 1/8 turn out on each coat to spray final coat at 1&1/8.
Anyways, I wanted waterborne to reduce the VOCs, I also wanted single stage for simplicity of repairs and doing a little at a time. I am not painting a show plane, I want it to look decent and hold up. I ended up picking Stewart.
Last paint I used was traditional BC/CC sherwin (not waterborne). It was a learning process, but came pretty quick. Stewart does not lay down like what I have used in the past. The primer nor the topcoat. The primer is more difficult to spray well than traditional BC/CC topcoats, at least in my experience; and the Stewart topcoat is even more difficult than their primer. However, neither take a PhD in painting, just some practice. Watch the videos numerous times, really think about what they are saying, and what to expect.
I would recommend the finishline gun, as I found known settings; this helped. Use a paddle in a drill to stir, don't shake the can.
My first attempt at spraying primer, I ended up with a really rough spotty finish. I prepped the metal according to them, but didn't spray according to them. I sprayed just like the AZKO I started with. Just tired to lay it down. Next time I did what they recommend, fog or tack coat, then laid down paint. Much better, however I tended to make more runs than desirable. What I ended up figuring out later was I needed to adjust the needle. I had the needle wide open and used distance from panel and speed of gun to regulate the spray onto the metal. This sort of worked, and I had good result sometimes; usually ended up with runs.
Top coats. I was really excited to spray the top coat, I start with some small panels and emp fairing. Well again the needle was full open. Results were horrible, ran like a race horse. When the white top coat runs it tends to bubble and the bubbles seem to propagate back to the primer. The bubbles are tiny, almost looks like intense solvent pop (and I think this is what it is). These runs are almost always not repairable, you end up sanding past the coat into the primer to get rid of the bubbles. So several re-attempts, still using my technique of speed and distance to regulate spray amount; never really worked. Finally, I did some googles and realized folks were starting with the needle almost all the way in, and backing it out a little at a time for each fog coat and final wet coat. I don't remember seeing this in the videos, and don't really remember doing this when I painted BC/CC; but I was at a rented booth and had help (they might have done this). Anyways, what I found was start at 3/4 needle out, move up 1/8 of a turn each coat to end up at 1&1/8 out for the 4th and final coat (wet coat). These settings seem to work really well for me, no runs doing this. I think I could maybe go 1&1/4; but no runs after a week of sanding off runs and multiple attempts makes me happy. Another important thing I found was the previous coat needs to be tacky but no longer transfer paint when touched. This was something on the video I ignored and just timed about 5-10 minutes. Some coats have taken up to 30 minutes to not transfer paint, 5-10 minutes doesn't work. I have used these things I've learned and the primer sprays well too now. I usually only do two fog coats, and open the gun a little more; also the fog coats dry quickly (no paint transfer to touch) compared to the top coats.
Bottom line, must do light coats building up to a wet coat, coats must be tacky but not transfer paint, and start gun at 3/4 needle out and adjust 1/8 turn out on each coat to spray final coat at 1&1/8.