Chemical bonded resin sand mould system has high dimensional accuracy, surface finish and sand mould properties compared to green
sand mould system. The mould cavity prepared under chemical bonded sand mould system must produce sufficient permeability and
hardness to withstand sand drop while pouring molten metal through ladle. The demand for improved values of permeability and mould
hardness depends on systematic study and analysis of influencing variables namely grain fineness number, setting time, percent of resin
and hardener. Try-error experiment methods and analysis were considered impractical in actual foundry practice due to the associated cost.
Experimental matrices of central composite design allow conducting minimum experiments that provide complete insight of the process.
Statistical significance of influencing variables and their interaction were determined to control the process. Analysis of variance
(ANOVA) test was conducted to validate the model statistically. Mathematical equation was derived separately for mould hardness and
permeability, which are expressed as a non-linear function of input variables based on the collected experimental input-output data. The
developed model prediction accuracy for practical usefulness was tested with 10 random experimental conditions. The decision variables
for higher mould hardness and permeability were determined using desirability function approach. The prediction results were found to be
consistent with experimental values.