A window muntin apparatus and system, and methods for forming the same. The muntins are formed from a substrate of a lignocellulosic material that has been applied with a desired muntin shape and machined by a computerized numerically controlled (CNC) machine. In general, the substrate of a lignocellulosic material is typically formed by impregnating a substrate of a lignocellulosic-material with an isocyanate-resin material, removing excess isocyanate-resin material from the impregnated substrate by impinging air at a high flow rate upon the impregnated substrate, polymerizing the resin by applying water to the impregnated substrate, the water being at a temperature sufficient for polymerization and removing the water from the polymerized resin-impregnated surface.