You are not the only one with Rapco spray can issues. My first thought is to warm the cans, (warm water bath). Then shake the crap out of the cans. The problem is that the paint isn't in huge demand, and it sits on a shelf for who knows how long. The paint will settle in the bottom, and becomes very difficult to remix. I have seen where a saws all is fixed with an attachment to shake spray paint cans. The warm water bath will help to speed up the process. Then when you do get the paint to flow and you finish with what you are painting, hold the can upside down and spray until only the aerosol comes out. This will clear the tip of paint. Some folks remove the tips, and leave to soak in solvent in between use.
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