The LME Laboratory Mixing Extruder is a unique laboratory tool developed to evaluate the processability of a variety of plastics and rubbers prior to production. From very fine powders to coarse materials, the LME will meet many extruding needs. The LME possesses a moveable header and dial gauge that allows for constant mixer adjustability. While in operation, the rotational shearing (mixing) is controlled by adjusting the distance between the end of the rotor and the inside header. This unique feature, not found in other extruders, allows for various extrudate mix levels in a single sample run. The rotational shearing of the LME system provides extensive and intensive mixing and can be used in the production of polymer blends or alloys. These blends have been found homogeneous enough to be spun into fibers over the entire range of composition. Since mixing may be independently adjusted, agglomerates of additives, such as fillers or pigments, may be accurately controlled.