I posted a question about a problem I was having with a crackling finish using water based polyurathe. I did a little experiment separating out a few variables, and found that that the problem was an incompatability with the shellac that I used as a sealer. The product did not specifically state any known problem with this, so for anyone else who might care to know, Ace brand, water based poly is not compatible with a shellac sealer. I am aware that other brands state that they are not compatable with shellac, but since the Ace does not say, I thought I'd point it out. Lesson learned.
Brian