[little chevy2]

I've been painting cars for a hobby for about 8 years . I've allways used sherwin williams or dimensions paint. Every time i paint lately it goes on shiney and looks good but as it dries it looks like sand was thrown in it.i've tried base coat, acrylic, and urethane and all the same. i've tried every reducer at every temp and air pressure that i could think of. iIclean the car with purple cleaner and dawn like i always have and wipe it down with western select paint prep. i've been told it was everything from the weather too hot ,to solvent pop, too contaminents in my air supply so i bought the best filters i cou' ld find painted when it was 60 degrees 75 and still got the same problem. I tried a different brand og paint in a spray can (valspar) and did'nt have a problem, i even used old paint from previous projects that did fine when i painted them but now it is messing up with the old paint too. I think it might be the reducer, is their any chance of something in the reducer might have been changed from the company? I'm about ready to give up and throw in the towel, but if anyone has an idea what might bee wrong it wou'ld bee greatly appreciated.

[baddbob]

List all of the products you've been using and the order in which they've been applied. Are you using lacquer primer? Any sealer? Epoxy primer? Urethane primer? Painting over an exhisting finish or starting from bare metal on up? There's lots of variables that can cause you die back problems but without enough information nobody is going to be able to help. Most dieback problems are related to solvents being trapped, I'm assuming the paint looks Ok with a good gloss when you're done spraying but then later the gloss goes away? Bob

[little chevy2]

I have started with western 2k primer surfacer and then water sanded with 500, cleaned with western surface prep, and painted with dimensions acrylic emamel. I have painted on primed and old paint surfaces both together and separate and got the same results. Up until 8 months ago i have not had this problem with this paint and i haven't changed anything in the last 8 years of painting.

[baddbob]

It sounds to me from the info given that it might be your air system. You say you painted something with an aresol that turned out OK but everything thats been done with a spray gun in the last 8 months has died out? Is your compressor using much oil-more than normal? Did you use the Western surface cleaner for the last 8 years? Something has changed, either you're using a product or proceedure you didn't use before or something is contaminating your air, or the rate the paint is drying....?

[baddbob]

maybe the reducer if there's been a formula change.

[adtkart]

A couple of things come to mind.

Check your air lines. Not the hard lines, but the hoses themselves. Over time, the air hoses will break down on the inside. You could actually have the pressure dropping while shooting. I have seen it before in fuel lines, where the line will have it's own flapper valve inside, due to breakdown of the hose.

What are you using to wipe them down with as far as rags. Alot of people, myself included, reuse rags for that. My wife does the laundry, and cleans them for me. If the detergent was changed, or she used fabric softner, that will cause problems. If you are purchasing special rags for that, try a different brand.

If you know someone that has a portable compressor, borrow that and shoot a test panel, like an old fender. See what that turns out like.

Just something to check.

Aaron

[little chevy2]

I have a friend who paints airplaines, i have gone to his shop and painted an old piece of fender with the same paint and got the same problem. I just bought new hoses 6 months ago. I am using a devillbus gti millinium gun and about 22psi at the gun.I wipe down with paper towels. Thanks for the info so far, it is greatly appreciated.

[DUCKY]

I "DO" think it's your reducer.
I had similar problems once and I tried everything and finally
gave up. But when I switched reducer brand they went away.
I was using a really cheap brand and just by accident I tried
a premium brand when it was real hot, ever since I quit using
the cheap one and haven't had the problem since.

[budthespud]

I had the same problem and it was contaminants in the air coupling. I now keep an air line just for painting so this won't happen again. So far so good.

[Bee4Me]

I believe its the reducer as well. IMO sand grit type finish is a sign of the product drying to quickly or dry spraying on the panel.
You've been using the same "everything" for quite a while,so It's GOT to be the product. Does any of this paint/primer use a hardner? Some of these hardner/catylist products have a VERY limited "open" life. Some as short as 1 month.
Only other thing might be the PSI your shooting at. Could the gun be malfunctioning or gun reg. if your using one?
If this paint use's a urethane grade reducer,I'd try switching brands and SEE if that helps.

[Bee4Me]

I just read your other question and I have some Martin Senour base and I HAVE to use THEIR reducer with. I don't know WHAT it is about it but I tried Nason & Dupont Basemaker and it would NOT flash right.
I got the Cross/FIRE reducer,CR234, and it sprayed fine.