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air pressur for orange peel

1K views 6 replies 5 participants last post by  bigsarg1 
#1 ·
well. I am painting my work truck to learn before I paint my replica McBurnie Daytona Spyder ( I call it a Cortona). So, I changed the truck's color from white to black (changing the Cortona red to black), learned a lot and after many redos I fill I have the knowledge to takel the Cortona. However, I have a lot of orange peel. I have sanded the door of the truck w. 1200 grit and then used compounds and buffed it to a great deep shine. If I sand the hole truck it will look great. But, I am not going to do that much work for the old work truck.

I have read many threads on orange peel and that increasing the air pressure will help. I am painting w/ an Astro Quantum 1.4 for the clear. Using 30 PSI with the trigger pulled while adjusting the PSI. I know you can not tell me exact numbers but should I start out at another ten or 5 PSIs. A rough number to start out w/ when adjusting will help. I have re-sanded my hood for this rehearsal and will BC Cc it again. I fell this is my final rehearsal before moving on to the Cortona. If the car comes out like the truck is I can sand and buff it to a perfect shine. But I would like to have as little O P as I can. Thanks in advance. You can email me also at

henry.bartlett@us.army.mil

additionally I paint the BC w/ a separate gun 1.3 and the 2K primer w/ a separate gun 1.9

And, can I use etching primer on the fiberglass repairs before hitting them w/ 2 K primer/

I am painting w/ PPG shop line BC/CC
 
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#2 ·
orange peel

I'am not a paint pro, the factory (Ford Mustang in the 60's) wanted a little bit of orange peel to hide the metal defects when too many parts were made from old dies, handling dings or dirty dies. I have painted a few cars and I usually got orange peel when the paint wasn't thinned enough or ambient temperature was to high for the paint -thinner mix. I usually try to spray with the gun needle turned down to less paint, and have enough light to see that you are getting a wet application. I sometimes would hold a light in one hand and the gun in the other hand.. I should have had an explosion proof set up but as the song says "we lived in a different world. had lead paint on our crib, rode our bikes with out helments, drank from the garden hose" etc drove 120 with out seatbelts or air bags
 
#4 ·
Don't use etch primer on fiberglass.
For less orange peel and better atomization you can do three things: bump your air pressure up, cut the fluid adjustment down-less trigger pull, and reduce your paint more. Make sure you're using the proper temperature reducers and hardeners-if they are too fast you won't get any flow, slower drying products are better for more flow and better gloss retention and they actually reach full cure faster. Get that gun dialed in better before you shoot the car-spray a few test panels first if needed. The fluid to air ratio is key for good atomization and once the settings are dialed in you'll need to apply it at a rate that delivers a slick wet but thin coat-watch the wetness in the reflection off your lights to tailor your application speed.
 
#5 ·
So ?

SO, you are saying keep the PSI at 30 and turn down the material knob 1/2 turn or so?

I paint w/ it wet about 1 ft behind the gun w/ the clear. Am I putting on too heavy a coat?

Orange peel is OK I guess if I want to sand for 20 hrs to get the shine I want. It is just I have been painting the truck for 2 months and have painted it twice (re dos), So I have the hole technique of spraying down to about 10% towards great. I just would like to paint the Cortona once and just have to sand the one or two runs out and be finished. I just read turn the PSI up to 50 on the last coat. WOW, that is more than I was going to practice w/.

Being retired I have the time and I am very patient and enjoy this very much.
My wife's car got hit in a parking lot and she was like I have another project for you. It is her front fender that needs a lit work and painting. I laughed and called the insurance company. I guess I do not like it that much.
 
#6 ·
Bump your air pressure up, just how much depends on too many factors to give you an exact psi. It's quite possible 50 psi is what is needed. What you are after is atomization. The clear must come out in a fog for you to get a smooth final coat. Over reduction is also a must for smooth clear.

Vince
 
#7 ·
clear has no reducer

The clear I am using only needs hardner and no reducer. Should I add 1 part reducer or decrease the hardner a bit? Should I apply this to all coats or paint the first two as I have been and apply this to the last coat only?
 
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