Casting covers major area of production all over the world. Resin bonded casting is widely used in today’s manufacturing industries. Furan

No bake casting is most widely accepted in indian foundries due to its excellent surface finish and dimensional stability. It is a self-setting

binder and it has a lower work and strip times. Though the casting process is also known as process of uncertainty, in the present study, an

attempt has been made to investigate the effect of Grain Fineness Number, Loss of Ignition, Potential of Hydrogen, % of Resin with

respect to sand, Sand Temperature and Compressive strength of the mould on Sand Inclusion defect – one of the most dominating defect in

the Krislur Castomech Pvt. Ltd. Industry situated at Bhavnagar, Gujarat, India. The experiments were conducted based on response surface

methodology (RSM) and sequential approach using face centered central composite design. The results show that quadratic model with

removal of some insignificant term is comparatively best fits for Sand Inclusion Defect.