spray paints going bad?

[deja-view]

I have a lot of spray cans that have gathered over the years...everything from Krylon, Dupli-color, Plasti-kote, etc. to regular model paints like Tamiya and Testor's. The last few times I wanted to use some of them a few wouldn't spray, but just dribbled out of the nozzle all over the place. The pressure was still there when I "tested" the lower tube below the nozzle, and the nozzles were clear. I do store a lot of my cans on their side (takes far less space and makes the shaking/mixing process much quicker).

So...are these paints just getting "old" and not able to be sprayed? Are the can/nozzle becoming corroded/corrupted somehow ( I have just moved from Las Vegas where moisture was never, ever a problem)? Have any of you grabbed a can of your favorite or chosen color for a project and had nothing but PHFttttttttttttt, dribble, dribble come out?

Edited September 3, 2013 by deja-view

[slusher]

l have bought paint like that but only a few times. l don't know if you should store paint on its side. l keep my paint at a controled temp and it keeps much longer..

[Dave Ambrose]

Sometimes the propellant will leak from the can. The paint is still there, but you can't spray it. I've had that happen to me on multiple occasions.