as the mold cavity 74 fills the rate proportionally increases to the optimum rate for the filling of the mold cavity 74 when the mold cavity 74 is approximately ninety percent 90 filled the maximum pressure set point of the hydraulic pump is lowered to a value which prevents the injection pressure from overcoming the clamp pressure the remainder of the material is injected into the mold cavity 74 allowing the pressure compensation characteristics of the pump to control the rate at which the material is injected this type of profiling describes a manner in which the tool is approximately ninety percent 90 filled using rate control with the last ten percent 10 using pressure control this is accomplished by the design of the hydraulic system and control software to begin the molding process the plastic injection material 68 is placed within the materials hopper 16 of the injection assembly 12 as the plastic injection material 68 is heated and plasticized within the injection assembly 12 the hydraulic cylinder 40 is actuated to move the slidable carriage 36 and movable mold section 48 into sealed engagement with the stationary mold section 62 as shown in fig4 when the movable mold section 48 and stationary mold section.