01 of 05
The Screw Extractor
They say good things come in small packages and that's true when it comes to this handy little tool called a screw extractor. When you have a screw head that is stripped or broken off or a bolt that has a stripped or broken off head, it can be impossible to remove without this tool. Screw extractors come in a range of sizes for screws of diameters ranging from 3/32 inch to upwards of 1/2 inch.
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- Drill and drill bit
- Screw extractor bit
- T-handle or locking pliers
02 of 05
Screw Extractor Design
A screw extractor is a high-strength steel shaft with a square head on one end and reverse tapered cutting screw threads on the other end. The square head fits into a T-handle that's used to turn it the extractor (see next slide). You can also grip and turn the head with locking pliers.
The tapered threads are at the business end of the tool. These are designed to screw backward, or counterclockwise, into the screw or bolt after a pilot hole has first been drilled. The end is tapered so that... the extractor digs into the damaged screw deeper and tighter as the extractor is turned. So while you're turning the extractor counterclockwise, it's digging into the damaged screw more and more while the damaged screw is backing out.Continue to 3 of 5 below.
03 of 05
The T-handle gets its name from its "T" shape. The handle fits over the end of an extractor bit and usually can be tightened with a knurled nut that works like a drill chuck. T-handles are made to fit a variety of extractor sizes, and many types also work with taps for threading holes, so they're not a uni-task tool. Again, if you don't have a T-handle, you can turn a screw extractor with locking pliers.Continue to 4 of 5 below.
04 of 05
How to Use a Screw Extractor: Step 1
Drill a pilot hole into the center of the damaged screw, using a power drill and the appropriate size of bit. If the head of the damaged screw is rough or uneven, it can help to start with a very small pilot hole, such as with a 1/16 inch bit. Then, drill a larger hole with the bit sized for the extractor. Keep the following tips in mind:
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- Since you're drilling in metal, keep the drill speed slow and steady; drilling too fast will overheat the bit and dull it quickly.
- Be very careful not to... break off the drill bit inside the hole, especially when drilling with small bits.
- The pilot hole diameter varies according to the extractor size you are using. Follow the recommendations on the package that came with the extractor.
05 of 05
How to Use a Screw Extractor: Step 2
Prepare the extractor and remove the damaged screw with the following steps:
- Grip the extractor bit firmly with a T-handle or locking pliers.
- Place the extractor bit into the pilot hole in the damaged screw.
- Using a hammer, tap the extractor firmly into the pilot hole.
- Apply downward pressure on the extractor while turning it counterclockwise to remove the damaged screw.
If the extractor slips and loses its bite in the screw, try these tips:
- Tap the extractor more firmly to get a better bite into the... screw.
- Push down more firmly as you turn the extractor counterclockwise.
- Enlarge the pilot hole slightly and try again.