Very nice!
Hmm how big is your tub?. Dimensions and volume? On the PG tutorial he used 50 gallon rubbermaid drum, with 1 cup of borax. I am using a 48 gallon container with 1 cup of borax.
I tried some more test dips tonight to mixed results. The temperature of the water and garage was stable. The first couple were exactly the same result, skinned over no good.Then we got 3 in a row to work , then 2 that didn't. This leads me to believe that the temp humidity and borax content must all be in perfect order for the viscosity of the paint you are using.Testors is the only paint i have used, but i think you can account for the drying time by adjusting the other factors ie thinning the paint,borax etc).I also believe that the water surface is critical.The first color down has to be the perfect viscosity and weight to create the exact surface for the other paint to move on.Too little and it dries and strands the other colors, too thick and it overloads and the colors clot.
here is one i did that worked
http://i151.photobucket.com/albums/s153/shrly2/swirls023.jpg