Hi. I'm trying to spray a car with a single stage metalic paint and I keep having problems. I have cleaned all the panels. Tried 3 different guns and 2 different brands of paint. No matter what I do I end up w what looks like popped bubbles. I'm using a 30 gallon tank. Mac tools hvlp gun set at 35 psi at the gun. Iv tried thinning my paint less and more than the manufacturers directions. Any advice would help.
Yes. I have a water filter on the tank and one of the little orange filters at the gun. Looks like it may be what people call solvent pop?? The paint was some cheap ebay stuff but had good reviews. I'm sure it's something I'm doing.
Are you waiting long enough before recoat? Or trying to cover too much area first p***. That coat could be " outg***ing" causing bubbles. In my experience for what it's worth don't try to completely " cover" 5the car the first spray. Build up to it over 3-4 coats allowing paint to flash/ dry in between. Full disclosure I'm not a pro painter and paint outside and have bugs in my clearcoat
Had that trouble with Nason on my 71 Monte Carlo had to respray hood 4 times and still got a couple pops.Didn't do it till I put the clear on.But used Valspar on my 40 and not one pop.Used PPG on y Model A and no pops so I guess it is with this paint stuff now days.Also a weekend painter in 2 car garage.
Sounds like what I call fisheyes. Which is caused by something on the undercoat that the paint doesn't like. Could be oil, could be the wrong undercoat.
Out g***ing of solvent more of a popped bubble look. Fisheyes pock or seperate down to the contamination.
You water trap should not be connected directly to your compressor. The general rule is 20 feet of hard line between it and the compressor. When your compressor is running a lot it gets hot. The air needs to cool down to get the water out. You also should drain your compressor before you paint you will be surprised how much water can be in there. A big shop drains the compressor daily.
I would have to say it's not fish eyes. Maybe I'm trying to lay it on too thick. I took a junkyard Hood, wiped it down with wax and grease remover. Sandeff with 400 Grit and shot a p*** over that and it still did it. I never have any problems with base coat clear coat. Just single stage. I sprayed a VW Bug about a year ago and it came out fine but I ended up using very little reducer in it. I think I may try this paint w no reducer and see what happens.
Ill also change my water trap location. I drained it before and it did have a lot of water from the last time I used it. Its a non oil type of compressor and they seem to make water really bad. I'll run a 25 ft hose from compressor to the separator then connect my air line. I have a feeling that may be the problem.
Are you using the same paint, hardener, and thinner made by and recommended by the same manufacture? Mixing different manufactures products can sometimes cause all kinds of problems.
Use a new hose from the separator to the gun. You might have contamination in the hose from previous use. I keep a hose that I only use for painting.
You really should try to find a piece of steel pipe. It cools better than the rubber hose. If you use rubber hose use a large diameter. 50 feet of 3/8 hose may be restrictive. It might not let you get proper air pressure at the gun.
You say you wiped the hood down, then sanded with 400. Are you wiping down with wax and grease remover after you are sanding with 400? Using a tack rag?
I agree, "solvent pop". make sure you wait the appropriate time between your first "light" coat, and second coats....if it says 30 minutes, give it 35-45 minutes.. just my experience. I have had to repaint a few times due to lack of patience.
I helped a friend out who was having similar issues. He was using the blue paper shop towels when he wiped it down with wax & grease remover. It did a good job of removing the **** in the towel, and transferring it to the metal. We went into the kitchen and stole some regular paper towels, a good wipe down and all was well.
I'm using a kit. So it's all by the same manufacture. Deff not orange peel. Iv painted alot of base coat clear coat and I know orange peel. New hose from compressor. I wiped car down w wax and grease remover before sanding. Then with 91% alcohol after car was masked. Tack raged it w air right before painting. Which leads me to think that it most likely is from water. I'm going to change my filter setup this afternoon. Paint a practice panel and see what happens.
"Tackragged with air",that might be your problem. Use a Real Tack rag NO air. You are just spraying contaminents back onto the surface your trying to clean.
I've seen a lot of professional painters use the air from there spray gun with a tack rag. That's the process that I was mimicking. But now I think that my Air Supply is contaminated and that might be my problem
Contamination comes from 3 places you. the environment, and the object you are painting. During the wax -n- grease removal process , out of habit DO NOT hold the Rag/Paper towel ON the can lid you poor from, it (the rag/paper)can contaminate the can, OR it (the can) may already be contaminated from before. And MAKE sure What you wipe with is pure/clean, and meant for body shop use. Make sure the neighbor guy, or ANYone in the AREA has not spritzed / sprayed Armor All within a 6 mile circle, well not that bad, but you get the idea.
Sometimes that can , or MUST be done , but for the most part, stay within the factory parameters/ instructions.
I'm no pro but I drained mine everyday and it was a 30 gallon tank and I was surprised at the amount of water that would drain out every nite from running all day, and u should move ur water separator at least 20 feet and I would put 2 on just to be safe I ran 2 and 1 oil separator and never had a problem but I think ur fish eye is from ur base coat I'll almost bet check with the company that makes the paint and ask them if they have a solution to ur problem if not try a diff primer jmo Sent from my iPad using The H.A.M.B. mobile app HotRod Harry
Wax and grease remover is meant to clean the surface before any paint prep or body work is started. A fast evaporating solvent such as PPG DX 320 is, in my opinion and experience, a better last cleaning material before spraying starts. I don't see the point of using compressed air along with a tack rag. Blowing off/out is best done earlier in the process to allow contaminants to settle and become trapped on the wet floor or ****ed out of the booth by the exhaust fan. A tack rag traps and removes particles from the surface and painting environment. Why blow them to another point on the vehicle or the painting environment ready to cause problems later?
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