USE/CARE OF HANDTOOLS & MEASURING TOOLS - OD1621 - LESSON 2/TASK 2
TYPES OF DRILLED HOLES.
USING A TAP AND TAP WRENCH.
(c) Check the tap for straightness in the hole by using a square,
as shown in figure 142 on the following page. Check to see that the tap is
in line with the axis of the hole and at right angles to the face of the
work. Check at more than one position around the tap.
(d) It is not necessary to feed the tap into the hole with any
pressure, as the threads will pull it in at the proper rate. Keep the tap
straight ((c) above).