Instructions:For checking threads
- Find a hole with a similar size to the object (a bolt, stud or screw to be checked) (fig.1)
- Connect the object to the hole to see if the hole matches the object.
Note: when the object threads match hole threads, the object can be rotated smoothly. If un-smoothness occurs, it is an indication that the threads do not match. Connection with force may cause hole threads damaged.
For checking diameter
- Position the object against the innermost part of the V-shape groove.
- Find the point where the edges of the object and the gauge touch each other (see the arrows on fig 2), and read the marking.
For checking length
- Place the object on both sides of the gauge (SAE on the right and metrics on the left).
- One end of the object should align the upper line of the gauge (fig.3 and fig.4) and read the marking.