Ceramic shell molds and methods of production

Claim 1

IN A MOLDING OPERATION INCLUDING THE STEPS OF PROVIDING A SET-UP HAVING A SPRUE AND A PLURALITY OF LATERALLY EXTENDING PATTENS ATTACHED TO THE SPURE, COATING THE SETUP WITH A REFRACTORY SLURRY CONSISTING ESSENTIALLY OF A RERACTORY POWDER SUSPENDED IN A BINDER SOLUTION, STUCCOING THE COATING WITH REFRACTORY PARTICLES, AND DRYING THE COATING TO FORM A REFRACTORY LAYER, AN IMPROVED PROCESS OF APPLYING THE REFRACTORY SLURRY COMPRISING PROVIDING A REFRACTORY SLURRY BATH, SUPPORTING THE SET-UP FOR ROTATION ON ITS HORIZONTAL AXIS AND SO THAT ONLY PATTERNS ALONG THE LOWER SIDE OF THE SET-UP ARE IMMERSED IN THE SLURRY BATH, AND ROTATING THE SET-UP SO THAT ALL OF THE PATTERNS ARE CONTINUOUSLY MOVED INTO AND OUT OF THE BATH AND SO THAT THE ATTITUDE OF THE PATTERNS IS CONSTANTLY CHANGED, WHEREBY THE SLURRY IS CAUSED TO FLOW OVER AND UNIFORMLY COAT THE SET-UP.