Abstract: An apparatus and method for creating and using a lightweight custom-molded orthopedic appliance are disclosed. The orthopedic appliance is made up of an inner and an outer bladder containing components which, when combined by rupturing the inner bladder, react to form a rigid foam substance which may be conformed to the shape of the body part or surface in need of support, cushioning, or immobilization, and which quickly cures to form a firm, supportive brace for the affected body part.