Where abouts are you doing your painting mate and storing your paints??
If it's in the garage at this time of the year, the cold is a major factor as it thickens up the paint which doesn't help. I go through this everyday at this time of year and there is nothing like it!
I do a couple of things -
I get all the paints I'm to use and stack them on the radiator to warm them through. This helps a great deal - It doesn't matter how much you thin it if the paint is stone cold when your loading up the airbrush.
Also I warm the areas I'm about to paint with a hair dryer as it helps with the initial bond of the first pass with the paint onto the lexan, and with the first coats spray at a relatively low PSI. Keep the hair dryer going as this flashes the WB paints off and will help when building up the coats, this will help stop the spidering
