The design of the screw extractor is elegantly simple. It consists of three elements:
- Square Head
- Shaft
- Reverse Tapered Cutting Screw Threads
The square head is mostly for being fastened into a "T" Handle that can be used with this tool to turn it (see next section). The square head can also be used to turn the extractor by using an adjustable wrench or vice grip pliers.
Shaft
The extractor is made of high strength steel and the shaft ties everything together. The vice grip type pliers can also be used to grip and turn the round shaft if desired.
Tapered Threads
This is the business end of the tool. The threads are designed to screw BACKWARD or counter-clockwise into the screw or bolt after a pilot hole has first been drilled. They are tapered so that the extractor digs into the damaged screw deeper and tighter and the extractor is turned. So while you're turning the extractor counter clockwise, it's digging into the damaged screw more and more and turns the damaged screw counter-clockwise which of course loosens and removes (extracts) the damaged screw. Simple huh?
