I want to/am currently in the process of swirl painting one of my guitars.
In swirl painting, you fabricate a colored film of oil paint on water with borax. The borax is used to better spread the color film. I think it increase the surface tension.
Now, since in Germany, as a private household you can't get borax anymore, so I can't get my hands on borax.
Does anybody have an idea of a substitute? My practical chemistry skills have gotten quite rusty after years of theoretical chemistry, so I could use some help here.
Soap wouldn't help because the oil paint would dissolve then (I think?).
Could I use a thinner for the oil paint? Would that give me the same results?
Or would you say borax isn't even needed?