When evaluating a previously owned lathe it is important to know if the headstock spindle runs true. The most accurate method is to determine the spindle runout with a machinist’s dial indicator. An acceptable substitute can be fashioned by chucking a sharp pencil, ballpoint pen or, better, a fine felt marker into the headstock. Hold a paper card flat against the tailstock and crank the tailstock until the card just touches the point of the writing instrument. Turn on the lathe. You can adjust the offering price downward depending on the size of the ovals that are drawn on the card.