How To Use A Screw Extractor
Introduction
Dealing with a stripped, broken, or damaged screw can be incredibly frustrating during any repair or DIY project. Fortunately, screw extractors are specialized tools designed specifically to remove these problematic fasteners. Learning how to properly use a screw extractor can save you countless hours of frustration, prevent damage to your workpiece, and help you complete your project successfully. This comprehensive guide will walk you through the entire process of using a screw extractor effectively, from preparation to execution.
What You’ll Need
Before starting the extraction process, gather these essential tools:
1. Screw extractor set (various sizes)
2. Variable speed drill
3. Appropriate drill bits (smaller than the screw diameter)
4. Center punch
5. Hammer
6. Penetrating oil (like WD-40 or PB Blaster)
7. Safety glasses
8. Work gloves
9. Adjustable wrench or pliers
10. Optional: Vice grips or locking pliers
Understanding Screw Extractors
Screw extractors are specialized tools with left-handed (counterclockwise) spiral flutes. They work by biting into a pre-drilled hole in the damaged screw when turned counterclockwise, which is the same direction used to unscrew most fasteners. Most extractors come in sets with different sizes to accommodate various screw dimensions.
Step-by-Step Guide to Using a Screw Extractor
Phase 1: Preparation
1. Assess the damaged screw to determine the appropriate extractor size needed.
2. Apply penetrating oil to the screw and surrounding area. Let it sit for 10-15 minutes to loosen any rust or corrosion.
3. Clear any debris around the screw head to ensure you have a clean working surface.
4. Put on your safety glasses and work gloves for protection.
Phase 2: Creating the Pilot Hole
1. Use the center punch and hammer to create a small indentation in the center of the damaged screw. This prevents the drill bit from wandering.
2. Select a drill bit that’s smaller than the screw diameter but large enough to accommodate your extractor. Generally, you want a hole about 1/4 to 1/3 the diameter of the screw.
3. Set your drill to a slow speed to prevent overheating the screw.
4. Carefully drill a pilot hole into the center of the screw. Apply steady, moderate pressure and drill to a depth of approximately 1/8 to 1/4 inch, depending on the screw size.
5. Keep the drill perpendicular to the surface to ensure a straight pilot hole.
Phase 3: Using the Extractor
1. Select the appropriate size extractor for your pilot hole. The extractor should fit snugly in the hole without forcing it.
2. Insert the extractor into the pilot hole by hand, applying downward pressure.
3. Once inserted, attach an adjustable wrench or pliers to the square end of the extractor.
4. Turn the extractor counterclockwise (left) with steady, even pressure. The flutes of the extractor will bite into the sides of the hole.
5. Continue turning counterclockwise until the screw begins to back out of the material.
6. Once the screw is loose enough, you may be able to remove it by hand or with pliers.
Troubleshooting Common Issues
If the Extractor Won’t Grip:
1. The pilot hole may be too large. Try a larger extractor or start over with a new pilot hole in a different location on the screw head.
2. Apply more downward pressure as you turn the extractor.
3. Ensure you’re turning in the correct direction (counterclockwise).
If the Screw Still Won’t Budge:
1. Apply more penetrating oil and let it soak longer.
2. Gently tap the extractor with a hammer to help it bite deeper into the screw.
3. Try alternating between clockwise and counterclockwise motions to break up corrosion (just a slight movement, not enough to damage the extractor).
If the Extractor Breaks:
This is unfortunately common with cheaper extractors or extremely stubborn screws. If this happens:
1. You may need to drill out the entire screw and extractor with a carbide bit.
2. Consider seeking professional help, as removing a broken extractor can be challenging.
Alternative Methods
If the screw extractor method isn’t working, consider these alternatives:
1. Use locking pliers: If enough of the screw head is exposed, grip it firmly with locking pliers and turn counterclockwise.
2. Try the rubber band technique: Place a rubber band between your screwdriver and the stripped screw head to create additional grip.
3. Cut a new slot: Use a rotary tool with a cutting wheel to create a new slot for a flathead screwdriver.
4. Weld a nut: For larger screws, weld a nut to the damaged head and use a wrench to remove it.
Frequently Asked Questions
How do I know what size extractor to use?
Choose an extractor that matches the size of your pilot hole. Most extractor sets include recommended drill bit sizes for each extractor. Generally, you want an extractor that’s slightly smaller than the screw diameter but larger than your pilot hole.
Can I use a screw extractor on any type of screw?
Screw extractors work on most types of screws and bolts, including steel, brass, and aluminum. However, they may be less effective on extremely hardened screws or titanium fasteners.
Why did my extractor break inside the screw?
Extractors can break if too much force is applied, if they’re used with a power tool instead of by hand, or if the extractor is of poor quality. Always use high-quality extractors and apply gradual, steady pressure rather than sudden force.
Do I always need to drill a pilot hole?
Yes, a pilot hole is essential for the extractor to work properly. Without it, the extractor won’t have enough material to grip and may slip or break.
How can I prevent stripping screws in the future?
Use the correct size and type of screwdriver, apply downward pressure while turning, avoid using worn-out bits, and don’t overtighten screws. For power tools, use the appropriate torque settings.
By following these steps and recommendations, you’ll be well-equipped to tackle those stubborn, damaged screws that stand in the way of completing your projects. Remember that patience is key—rushing the process often leads to more complications and potential damage to your materials or tools.