Gauge maker's tolerance.1. first system as shown in fig 4.50In this method workshop and inspection gauges are made separately and their tolerance zones are different.

2. second system (revised gauge limits) as shown in fig 4.51Under this system the disadvantages of inspection gauges are reduced by reducing the tolerance zone of inspection gauge and the workshop gauge tolerance remain the same.

Gauges for tapers:a taper is tested by using taper plug and ring gauges. the important thing in testing a tapered job is to check the diameter at bigger end and the change of diameter per unit length.