>>10450209When you spray paint from a can into a container (and not into the open air), the propellant gets trapped and has no time to evaporate into the air (as it does when you spray paint a surface from a can).
The propellant then proceeds to evaporate at its natural rate, as it does the paint where it evaporates from (and the container where the paint is) gets cold (as to why, see physics textbook). Eventually it passes the freezing point (and the water that condensed on the container turns to ice).
You need to wait until the container warms up (on its own) back to the room temperature, which would indicate that the evaporation is finished. If you put anything into the container while it's still below room temperature, it will cause the remaining propellant to boil and make a mess.
In short, spray the paint into the container and leave it alone until it is not cold to the touch. Then you replenish the thinner (which also evaporated) and close the container. When you open it next time, do it slowly until you see no bubbles form upon opening.
Mixing the paint continuosly speeds up evaporation and minimizes thinner losses, but DON'T mix it with a stick, the mixer has to be the same temperature as the liquid, which is why magnetic stirrer works so well.
>>10450210That's a real short straw, doesn't give the paint much time to expand until it hits the container. I use a 6"+ (20cm+) piece of silicone tube that fits the spray nozzle and dip the other end into the bottle.
