Is it ok to apply a clay slip over another clay body that have different shrinkage rates? For example, I'd like to apply Standard 710 with a shrinkage rate of 11.5%, over a sculpture made of Standard 420 with a shrinkage rate of 10%. Are the shrinkage rates close enough that I won't have cracking or other issues? It would be a thin coat, just enough to change the color.
At what point will the differences in shrinkage rates cause problems? I'm assuming the greater the difference, the more likely it would be to have problem.
Should I add anything to the slip to improve brushability? (That wouldn't affect the glazes.) I'm doing this because I love how glazes look on 710 but 420 is better for building.
I fire to cone 5.5 in oxidation if that makes any difference.
thank you!