Screw Extractor: How to Choose and Use One

What Is a Screw Extractor?

A screw extractor is a removal tool made from hardened steel that helps you take out damaged screws that no longer accept a standard driver. It works by biting into a drilled hole or the damaged head and turning the screw out counterclockwise. Many kits include matching drill bits and extractors sized for common screw diameters.

How It Works

Most extractors rely on two steps:
1. Create a centered pilot hole in the damaged screw (or use a built-in cutting end on some extractor bits).
2. Drive the extractor into that hole and turn it in reverse. The extractor’s cutting edges or flutes grip the screw as torque increases, backing the screw out.

Some extractors are used with a reversible drill set to slow speed. Others are turned by hand with a T‑handle tap wrench, adjustable wrench, or a small ratchet for better feel and control.

Common Uses in DIY and Home Improvement

Stripped hinge screws in door frames
Rusted deck screws with heads that crumble or cam out
Snapped screws in furniture repairs or fixtures
Corroded license plate screws on vehicles or exterior gates
Stuck cabinet hardware screws in soft wood

Using an extractor can save trim, drywall, tile, and other finished surfaces by avoiding over-drilling or prying.

Types of Screw Extractors

Spiral (tapered) fluted extractors: The most common type. The tapered, reverse spiral digs deeper as you turn counterclockwise. They’re fast and effective, but the taper can expand thin screws, making them tighter.
Straight-flute extractors: Cylindrical and usually driven into a drilled hole with a light hammer tap, then turned with a wrench. They reduce the wedging effect and are a smart choice for brittle or thin-walled screws.
Multi-spline extractors: Short, strong extractors with multiple splines. Often used for bolts too, paired with drill guides.
Two-step “damaged screw remover” bits: One end cuts or burns a new recess in the head, the other end bites and turns. These are great when the screw head is stripped but the shank isn’t broken.
Left-hand drill bit method: While not an extractor, a left-hand drill bit can sometimes grab and spin the screw out during drilling. Many kits include them because they reduce the need for a separate extractor.

How to Choose the Right Extractor

Match size to the screw: Pick the extractor size recommended for your screw diameter. Too small slips; too large can break or damage the work.
Consider material and condition: For rusted or heat‑treated screws, use high-quality extractors and cobalt or high-speed steel left-hand bits for the pilot hole.
Select flute style for the job: Straight-flute for thin or brittle screws to reduce expansion; spiral for general household screws where speed matters.
Look for a complete kit: A kit with matching left-hand bits, drill guides, and a T-handle makes setup easier and more accurate.
Ergonomics and control: If you’re new to extractors, choose a hand‑turned setup (tap wrench) to avoid over-torque from a drill.

Step-by-Step: How to Use a Screw Extractor

Prep the area: Clear debris. If the screw is rusty, apply penetrating oil and let it soak 10–20 minutes. For stubborn rust, alternate heating the area gently and letting it cool to break the bond (avoid heat near finishes or flammables).
Stabilize the work: Clamp the workpiece if possible. Wear eye protection; hardened extractors can chip if overloaded.
Mark the center: Use a center punch to mark the exact center of the screw. Centering reduces the chance of drilling off-angle.
Drill a pilot hole: Use the left-hand drill bit size specified by your extractor kit. Run the drill in reverse at slow speed. Sometimes the screw backs out during this step—great! If not, proceed.
Insert the extractor: For spiral types, tap the extractor lightly into the hole. For straight-flute, seat it firmly as instructed.
Turn counterclockwise: Use a T-handle or small wrench. Apply steady, moderate torque. If it doesn’t budge, stop and re-check. More force is not always better.
Work the screw free: Slight rocking (a small back-and-forth motion) can help. Re-apply penetrating oil if needed.
Remove and inspect threads: Once the screw is out, clean the hole. If threads are damaged, chase them with a tap or install a thread insert (e.g., Helicoil).

Common Mistakes to Avoid

Using a forward (right-hand) drill for the pilot: This can tighten the screw. Use left-hand bits in reverse when possible.
Choosing the wrong extractor size: Leads to slipping or breakage. Follow the kit’s chart.
Drilling off-center: You’ll thin the screw wall on one side and reduce grip. Use a punch and drill guides.
Applying excessive torque: Hardened extractors are tough but brittle. If one snaps in the hole, it’s very hard to drill out.
Skipping lubrication and patience: Penetrating oil, heat/cool cycles, and gentle persuasion save time compared to brute force.
Letting the taper wedge the screw tighter: For thin or hollow screws, try a straight-flute extractor to avoid expansion.

Care and Maintenance

Keep bits sharp: Dull drill bits wander and overheat. Replace worn left-hand bits.
Prevent rust: Store extractors dry; wipe with a light oil film.
Organize sizes: Keep the kit intact so the extractor matches the recommended pilot bit.
Avoid overheating: Use slow drill speeds with cutting oil on metal to protect both bit and extractor.

Related Terms and Tools

Left-hand drill bit: A reverse-spiral bit that can loosen a screw during drilling.
Tap wrench: A T-shaped handle for controlled, straight turning of extractors and taps.
Impact driver: Helps remove stuck screws before you resort to extractors.
Thread repair insert (Helicoil): Restores damaged internal threads after extraction.
Penetrating oil: Low-viscosity lubricant that seeps into threads to break rust bonds.

Practical Examples

Stuck door hinge screw: The Phillips head is rounded over. Try an impact driver first. If it slips, use a two-step remover bit: cut a new recess, flip the bit, and back it out. If the head snaps, switch to a straight-flute extractor to avoid wedging in the soft jamb wood.
Snapped deck screw in a joist: Center punch the broken shank, drill a small left-hand pilot, and attempt reverse drilling. If it doesn’t spin free, use a spiral extractor with steady hand torque. After removal, clean the hole and install a fresh screw of the correct length.
Rusted license plate screw: Soak with penetrating oil, heat the nut side gently if accessible, then use a spiral extractor. Protect paint with masking tape and move slowly to avoid slips.
Cabinet knob screw spinning in place: If the head is stripped but intact, try a damaged screw remover bit to create a fresh bite and turn it out without marring the cabinet face.

By choosing the right extractor type, drilling accurately, and working patiently, you can remove damaged screws cleanly and keep your project on track.