I have a question about spray paint?

[david bailey]

Does spray paint every go bad??? I bought some from Wal-Mart off the shelve and treid spraying with it and all it does is sputter like it clogged up.I did like i always do with paint,i shook for about five minutes,i alsdo heated in water. The weather was nice in the mid 70s,i Also changed the nozzle on the can with a spare.and it still acted the same. Not only that but it was the good paint KRYLON,Not the cheap stuff.I went back to Wal-Mart to get another can ,to see if i have the same problem again.And the second didnt act like that.Could it be i got a bad can or paint someone elses returned??I also asked the people in the paint department how often do they rotate there stock.

[dizzyfugu]

Yes, rattle cans can "die". Had this case only once, though, with a very old acrylic paint that was already a couple of years old when I bought it. Worked fine when freshly used, but then, months/years later, when I wanted to use the paint again, it sputtered and was done. I assume that the pigments clump together, and that the compressed air diffuses from the can, so that the whole mechanism does not work anymore.

[Malcolm M]

It's only happened once to me and with a can of WalMart primer. It was fine for a few weeks then I put it away and the next time it shook fine no obvious clumping in the can but when I tried to spray it a thin stream of what resembled cream came out. I can only guess the propellant might have leaked reducing the pressure...I don't know