USE/CARE OF HANDTOOLS & MEASURING TOOLS - OD1621 - LESSON 2/TASK 2
c. Use of Extractors.
(1) Before using an extractor, make certain broken chips of screws,
bolts, or taps are removed from the hole. A sharp pointed tool, such as a
scriber, or a small brush may be used for this purpose.
(2) The use of the straight fluted type extractor (figure 148)
requires that a well-centered small hole be drilled in the broken unit
first. Enlarge the hole to receive the extractor tool. The correct drill
size is one size less that the extractor size to be used.
FIGURE 148.
USING STRAIGHT FLUTED TAP AND SCREW EXTRACTOR.
(3) Drive the extractor into the hole, slip the turn nut over the
extractor, turn it counterclockwise, and turn out the broken unit.
The
flutes will grip the walls of the drilled unit and remove it without
damaging the threads of the tapped hole.
(4) For screws or taps that are broken off below the surface, use the
correct size guide to center the drill before drilling the first small hole.
Enlarge the hole as before. Remove the drill and insert the extractor into
the hole.
Slip the turn nut over the extractor and turn out the broken
screw or tap.
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