Using a bolt extractor is a common method for removing stubborn or broken bolts, screws, or studs when a standard tool cannot grip them. It works by biting into the damaged fastener, allowing you to unscrew it.
Here's a breakdown of how to use a bolt extractor:
Preparing the Damaged Fastener
Before you can use an extractor, you need to prepare the fastener:
- Clean the Area: Remove any rust, dirt, or debris around the damaged bolt head or shaft.
- Locate the Center: Use a center punch to mark the exact center of the bolt or screw you need to extract.
- Drill a Pilot Hole: Using a drill bit that is smaller than the bolt's diameter (the extractor set usually specifies the correct drill bit size), drill a hole into the center of the damaged fastener. Drill deep enough for the extractor to get a good grip, but be careful not to drill all the way through if possible.
Selecting and Using the Extractor
Choosing the right extractor and inserting it properly is crucial for success.
Step-by-Step Extraction
Here are the steps involved in using the bolt extractor:
- Select the Right Size: Choose an extractor that matches the size of the pilot hole you drilled. Extractor sets come in various sizes, often color-coded or marked with numbers.
- Insert the Extractor: Place the pointed end of the extractor into the pilot hole.
- Tap the Extractor: You'll need to find the right amount of force to tap the extractor in. Use a hammer to gently tap the extractor into the hole. This forces the extractor's threads or splines to bite into the metal of the damaged fastener. Not enough force and the extractor won't bite into the hole. It might take a few attempts to get it seated correctly and biting firmly.
- Apply Turning Force: Once the extractor is firmly seated and has a good bite, attach a wrench or tap handle to the other end of the extractor.
- Unscrew Counter-Clockwise: Slowly and steadily turn the wrench or handle counter-clockwise. As you turn, the extractor's reverse threads will grip tighter into the damaged fastener, eventually turning it out of the hole.
- Remove the Fastener: Continue turning until the damaged bolt or screw is completely removed.
Practical Tips for Success
- Lubrication: Applying a penetrating oil to the seized fastener before starting can significantly help loosen it. Allow the oil time to work.
- Heat (Caution!): In some cases, carefully applying heat around the area (not directly to the bolt unless necessary and safe for surrounding materials) can help break the bond of rust or threadlocker. Use caution and appropriate safety gear.
- Steady Pressure: Apply steady, even pressure when turning the extractor. Jerking motions can break the extractor, making the situation worse.
- Multiple Attempts: As the reference notes, if the extractor doesn't bite initially or the bolt is very stubborn, it might take a few attempts to seat the extractor properly or to get the bolt to turn.
- Extractor Types: Be aware there are different types of extractors (e.g., spiral flute, square head). The method described above primarily applies to spiral flute extractors, which are common. Always follow the specific instructions for your extractor set.
Using a bolt extractor requires patience and the right technique, particularly getting the extractor to bite firmly into the damaged fastener as described in the reference.
