That sucks Don. When you are ready for the Vallejo, shake the crap out of it and when you are done, shake it some more. Let the model sit 24 hours or more if you are going to do any masking. While you can use it straight out of the bottle, I always add their flow improver if I am spraying a large area. I spray for about 5 seconds and then send a blast of straight air through the AB to remove any paint build up on the tip. I do this with all acrylic paint. Follow Vallejo's clean up instructions. DO NOT USE IPA TO CLEAN-UP unless you like a gummy nightmare