A molding system including an extruder assembly, a screw assembly having a longitudinal central axis, and a screw-moving assembly, the screw-moving assembly comprising a screw-moving actuator and a bias adjustment mechanism, the screw-moving actuator and the bias-adjustment mechanism being configured to connect to the screw assembly, the screw-moving actuator being configured to transmit, in use, a screw-translation force to the longitudinal central axis of the screw assembly, and the bias-adjustment mechanism being configured to transmit, in use, a biasing force to the longitudinal central axis of the screw assembly, the screw-moving actuator including an electric-motor assembly,a rack-and-pinion assembly a shaft assembly, and a piston assembly, the electric-motor assembly being coupled to the rack-and-pinion assembly, the rack-and-pinion assembly being coupled to the shaft assembly, the shaft assembly being coupled to the piston assembly, and the piston assembly configured to be coupled to the screw assembly; the bias-adjustment mechanism including a fluid-based actuator having a single piston arrangement and a fluid-reservoir assembly configured to accommodate, in use, a fluid consisting of a liquid or a flowable solid; the single piston arrangement contacting the fluid-reservoir assembly and being coupled to the screw-moving actuator, and characterised in that the bias-adjustment mechanism further includes: a first lock valve assembly; a first reservoir assembly; a second lock valve assembly; a first accumulator assembly; a fluid-supply assembly; a pressure-regulator assembly; a second reservoir assembly; a second accumulator assembly; a first pressure-transducer assembly; a second pressure-transducer assembly; the first lock valve assembly is in fluid communication with the fluid-reservoir assembly; the first reservoir assembly is coupled to the first lock valve assembly; the second lock valve assembly is in fluid communication with the fluid-reservoir assembly; the first accumulator assembly is in fluid communication with the second lock valve assembly; the pressure-regulator assembly is in fluid communication with the second lock valve assembly and with the first accumulator assembly; the fluid-supply assembly is in fluid communication with the pressure- regulator assembly; the second reservoir assembly is in fluid communication with the pressure-regulator assembly; the second accumulator assembly is in fluid communication with the pressure-regulatorassembly; the first pressure-transducer assembly is configured to sense pressure of the first accumulator assembly; and the second pressure-transducer assembly is configured to sense the pressure of the second accumulator assembly. a first lock valve assembly; a first reservoir assembly; a second lock valve assembly; a first accumulator assembly; a fluid-supply assembly; a pressure-regulator assembly; a second reservoir assembly; a second accumulator assembly; a first pressure-transducer assembly; a second pressure-transducer assembly; the first lock valve assembly is in fluid communication with the fluid-reservoir assembly; the first reservoir assembly is coupled to the first lock valve assembly; the second lock valve assembly is in fluid communication with the fluid-reservoir assembly; the first accumulator assembly is in fluid communication with the second lock valve assembly; the pressure-regulator assembly is in fluid communication with the second lock valve assembly and with the first accumulator assembly; the fluid-supply assembly is in fluid communication with the pressure- regulator assembly; the second reservoir assembly is in fluid communication with the pressure-regulator assembly; the second accumulator assembly is in fluid communication with the pressure-regulatorassembly; the first pressure-transducer assembly is configured to sense pressure of the first accumulator assembly; and the second pressure-transducer assembly is configured to sense the pressure of the second accumulator assembly.