Scalex problems in enameling

I’m having difficulty in getting Scalex (ball clay) to work
consistently inpreventing oxidation during enameling. I paint it on
copper sheet where Iwant to avoid oxides, put enamel on the other
side, let it dry and fire. The scalex is supposed to flake off after
cooling (with no oxidation underneath), but sometimes it flakes off
during firing and I end up with areas ofoxidation on the metal. I’d
appreciate any hints, tips or suggestions that you have. Thank you.


I remember when Scalex really did the job. It was gray and not the
tan color it now is. Obviously something has changed in the mix.
Perhaps Thompson Enamels could tell us what that might be.


If the Scalex comes off in the kiln, often the metal was not
completely grease free before application. Donna in VA