Oops, guess that panel didn’t work well, it was completely destroyed, turned out it was the raku clay and all the other models that had been fired were a different clay. The raku clay should have been better that the other clay since it’s designed for rapid heating and cooling.
Oh well, no real loss since I have a mold of it, but it was a surprise it had started cracking and breaking before the kiln was even 700 degrees.