The Screw Extractor: All craftsmen have experienced the terror and toils of stuck bolts and screws; these tasks can quickly turn into some of the toughest jobs in the shop. When a screw or bolt gets stuck, or its head has been stripped or broken, it can be truly impossible to extract it. Craftsmen will go to excessive lengths, using excessive force to remove these frozen screws; but when the dust settles, craftsmen find the screw extractor. A screw extractor is a small, and yet miraculous device that gets into the center of a stuck screw, and releases its grips from the inside out.
The screw extractor is a small tool with big results designed to dive into the interior of a stuck screw (through a pilot-hole), bite into the it and turn the screw out counter-clockwise. Screw extractors range to fit screw-heads from 3/32" and 1/2" in diameter. They are built with a square head and shaft on one end and reverse tapered (cutting screw) threads on the other. The square head is designed to be fastened to a T-handle providing leverage to turn the extractor into the frozen screw. The square head can also be turned with vice grip pliers or an adjustable wrench. Extractors are manufactured with superior grade steel so that the shaft can be gripped with vice grips or an adjustable wrench for additional force or turning power. The extractors tapered threads are the real muscle of the device biting into the insides of a screw. The treads are designed to turn counter-clockwise, or backwards, reverse drilling into the center of a screw to pull it out. As the extractor is turned, it bites down tighter and digs deeper into the frozen screw and eventually begins turning the damaged screw with it. Essentially the extractor reverses the screw out of its frozen position.
Extraction: Drilling a pilot-hole into the damaged screw is the first step to getting it out: With a power drill, drill a hole into the center of the damaged screw's head. Start by using the smallest drill bit available and work your way up to a larger sized bit for a larger pilot-hole. Because the size of the pilot-hole will vary depending upon the size of the extractor, the extractor should come with a bit size recommendation on its packaging; this should help eliminate most of the guess work on your part.
After drilling the pilot-hole, firmly grip the extraction bit with a T-Handle or pliers and insert the extractor into the pilot-hole. Tap the top of the extractor with a hammer to secure it firmly into the screw. While exerting downward pressure on the extractor, turn it counter-clockwise (to the left) to begin releasing the stuck screw. If turning the extractor is difficult or unstable, tap the extraction bit down a bit more firmly into the screw. This should give the threads a better hold, and better biting power into the screw. You may also press down a bit more firmly on the top of the extractor, but be careful not the break the extraction bit off into the stuck screw. If a better bite, or increased pressure doesn't make the process any easier, you may try enlarging the pilot-hole. Slightly enlarge the pilot-hole and attempt the process again. This should have that stubborn screw out in no time.
Sometimes stuck screws or bolts can prove to be one of the biggest frustrations in the shop. Using a screw extractor, however, can eliminate that stress and get that screw loose with minimal time and effort. Before resorting to the most drastic measures, the screw extractor provide relief in eliminating that stuck screw.