I sprayed the light sand color from tamiya TS 46 into a jar and baaam it worked. I used a drinking straw from wal-mart and it worked out great put the one end on the round part that sprays paint and put the straw in jar.. An also angle the jar about 45 degree angle ; then raise the angle as the jar becomes full.The only bad thing is you have to wear gloves so you don't get paint all over your hands. So the spray doesn't spray back out of the jar. I got 1 normal paint jar done and might get two.
Happy Modeling
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(++) 1:35
PS Now I can use other colors only offered in spray cans.