If clay is not fully cured all the way through- which means the heat has to reach the center of the sculpt for the full required time needed to cure- and that’s hard to accomplish in just a few minutes- (it takes longer depending on how dense the clay is)- then the clay on the inside of the sculpt doesn’t turn completely to solid. The partially cured clay on the inside of the figure will weaken the outer, hard shell of clay that IS cured- and cause it to deteriorate and crumble. This happens over time. You can’t see it or tell when the piece is first made.
This is why I hear about collectors who have pieces in their collections that are displayed in cabinets, not touched- and eventually ‘the arm fell off’ or the leg cracked. The oils in the clay ‘eat’ their way out and cause the outer, hard baked shell to crack. That’s why I use an armature, covered in clay and pre baked so that’s solid– that gives strength and correct proportions to the figure- and then the outer layers of clay are not thick and will cure all the way to the armature.
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