Snow [1998] suggested that up to 90% of all shell cracking is a result of the autoclave de-waxing cycle and that the majority of cracks are caused by bulk expansion of the wax as it is heated. Wax expansion produces stresses in the shell. If the induced stress becomes greater than the shell’s strength, the shell cracks. Therefore, minimizing wax expansion during melting should eliminate/minimize cracking. A clearer understanding of the factors affecting wax melt profiles can be gained through computational fluid dynamics (CFD) by modeling the interaction among wax thermal conductivity, shell thermal conductivity and autoclave temperature. The most favorable melt profiles result in low interior temperatures when melting is completed on the outer surface of the wax. For the first time, is has been shown that a high autoclave temperature (182°C), water saturated shell thermal conductivity (1.40 Wm-1k-1), and low wax thermal conductivity (0.30 Wm-1k-1) should result in a favorable melt profile. These parameters reduce the likelihood of shell cracking as a result of wax bulk expansion by reducing core temperature by as much as 21°C.