[swedishsteel]

I have found that they need to be shaken a LONG time, with theory being they have sat for a long time on a store shelf and all the pigment settles to the bottom, just like in a gallon can of paint. I have a vibratory parts polisher with a bowl and when I'm going to use a can of spray paint I shake it in that for several minutes, the longer the better. Since I started doing that I've had few problems with clogging. Just yesterday I used up several partial cans on the interior of a '67 Mustang body--it's a coat of many colors but it will all be covered and I just wanted a coat of paint on the steel--and none of the old cans plugged up. Just for insurance I keep several nozzles sitting in a closed container submerged in lacquer thinner.