Performance depends very much on the condition of the leadscrew, so the leadscrew should be cleaned periodically for best results. To clean the screw, first use isopropyl alcohol to dissolve old grease and contaminants. There are plastic components that may be damaged by some strong solvents. Apply a small amount of grease. The grease will reduce friction, backlash and sticktion. We use NyeClean 5077 vacuum grease available from www.nyelubricants.com. A similar grease with a compatible thickener and lubricant are also suitable.