Ordinary marking gauges tend to follow the grain of the wood and often have trouble marking a straight line. If used improperly the marking pin will sometimes drift with the grain or start to chatter and give unsatisfactory results. Wheel Marking Gauges solve these problems. They exhibit less tendency to drift with grain or to chatter and their hardened, beveled wheels leave a straight, almost hairline thin mark. Since the wheel is both sharp and beveled, it cuts through erratic grain while forcing the gauge face against the stock to maintain accuracy.