How do you remove a stripped Allen screw?

Allen screws, also known as hex screws or hex bolts, are a popular type of fastener characterized by an internal hexagonal socket in the head. This socket allows tightening or loosening the screw with an Allen wrench or hex key. However, Allen screws are prone to stripping if too much torque is applied or if the wrong size hex key is used. A stripped Allen screw has rounded internal edges in the socket that prevent the hex key from getting proper purchase to turn the screw.

Removing a stripped Allen screw can be challenging, but there are several methods you can try to extract the stubborn fastener. This article provides step-by-step instructions on 5 different techniques for removing stripped Allen screws:

• Using vice grips or pliers
• Using a screw extractor
• Drilling out the screw
• Using a Dremel or rotary tool
• Filling the socket with super glue or epoxy

Read on to learn how to deal with a stripped Allen screw and restore your equipment to working order. With some patience and the right tools, you can remove the stripped fastener.

Using Vice Grips or Pliers

Vice grips or locking pliers are a good first option for removing a stripped Allen screw. The key is clamping the vice grips as tightly as possible onto the outside of the screw head. This may give enough grip to unscrew the fastener by turning the vice grips counterclockwise. Here are the steps for this method:

1. Select vice grips or curved jaw locking pliers that will fit over the Allen screw head.
2. Clamp the vice grips tightly onto the screw head, as close to the base as possible.
3. Turn the vice grips counterclockwise to loosen and back out the Allen screw.
4. If the screw won’t budge, try tightening the vice grips further or hammering on the vice grips handle to vibrate the tool while turning.
5. Repeat the process if the vice grips lose grip on the screw.

Vice grips provide extra leverage and gripping power compared to Allen wrenches. The ridged teeth on the vice grips jaws dig into the screw head for traction. This method works best on Allen screws that are not completely smooth or rounded off.

Using a Screw Extractor

A screw extractor is a specialty tool engineered for removing stripped or stubborn screws. Extractors bite into the screw head and provide reverse threading to back the screw out when turned counterclockwise. To use a screw extractor:

1. Select an extractor bit that matches the size of your Allen screw.
2. Use a center punch tool and hammer to make an indent in the center of the screw head.
3. Press the extractor into the indent and turn it counterclockwise with a wrench.
4. Apply firm downward pressure while turning the extractor to keep it seated in the screw.
5. Continue turning counterclockwise to back the screw out of the hole.

The key with screw extractors is letting the tool do the work—don’t force it. The extractors are made of hardened steel and will chew into the screw with applied downward force. Lubricating the extractor and screw with penetrating oil can also help facilitate the process. Screw extracting kits are available at most hardware stores.

Drilling Out the Screw

If other methods fail, drilling out the Allen screw is an option. Use a drill bit slightly larger than the screw shaft (not the head) to bore out the screw. Here is the process:

1. Select a drill bit 1-2 sizes larger than the minor diameter of the Allen screw shaft.
2. Mark the screw’s center point with a center punch.
3. Use a low RPM setting on the drill to avoid excess friction and overheating.
4. Drill into the exact center of the screw, applying firm pressure.
5. Frequently back the bit out to clear metal shavings that can bind the drill.
6. Once the drill cuts through the full thickness of the screw, it will spin freely.
7. Switch to a larger bit if needed to finish clearing out the screw.

The goal is to drill deep enough through the center of the screw to sever it, allowing you to then easily unscrew the remaining portion by hand or pliers. Take care not to drill too deeply and damage the equipment threads underneath. Remove any burrs or leftovers with a screw tap tool.

Using a Dremel or Rotary Tool

A Dremel rotary tool provides another option for cutting, grinding, and polishing out a stripped Allen screw. Follow this process:

1. Select a small, thin grinding wheel, carbide bit, or metal cut-off wheel accessory.
2. Use a low speed on the Dremel tool (15,000 RPM or less).
3. Hold the grinding wheel at a 45° angle to the Allen screw recess.
4. Carefully grind and smooth out the interior of the socket to make it round again.
5. Test fitting an Allen wrench and continue smoothing the socket as needed.
6. Once an Allen wrench fits snugly again, unscrew the fastener.

Dremel tools allow precise, controlled removal of metal to reshape the damaged Allen socket. Take it slow and smooth to avoid excess cutting. The interior socket just needs rounding out enough to accept an Allen wrench for removal.

Filling the Socket with Super Glue or Epoxy

Filling the Allen socket with a glue or epoxy resin can re-shape the damaged interior so a hex wrench fits snugly again. Cyanoacrylate super glue and JB Weld two-part epoxy work well for this technique. Here’s how to do it:

1. Clean out the interior of the Allen screw socket.
2. Fill or overfill the socket with super glue or mixed epoxy resin.
3. Allow the adhesive to fully cure per the manufacturer instructions.
4. Use a small round file to shape the cured glue down to the size of a new Allen socket.
5. Test fitting a hex wrench and file/sand the socket down gradually until the wrench fits tightly.
6. Insert the Allen wrench fully into the socket and unscrew the fastener.

The cured glue or epoxy fills in the stripped socket and provides fresh material for cutting new hex socket sides. Filing the adhesive down flush with the top of the screw head also helps grip the wrench. This method works well for deeply damaged screws with minimal intact metal remaining.

Preventing Stripped Allen Screws

Prevention is the best solution for avoiding the headache of removing stripped Allen screws. Here are some tips:

• Use the correct size hex wrench – never force a mismatching Allen key into the socket.
• Apply inward pressure when tightening screws to keep the wrench seated fully.
• Use a ball end Allen wrench for better angled access in tight spots.
• Lubricate screws and wrench with machine oil or WD-40 for easier tightening/loosening.
• Avoid overtightening Allen screws beyond hand tight levels.
• Consider replacing worn Allen screws for easier ongoing use.

Following torque specifications and using quality hex wrenches sized for the screw can go a long way toward avoiding stripped Allen heads. Also inspect equipment regularly and address any loose Allen screws before they become damaged.

Choosing the Best Method

Selecting the right stripped Allen screw removal technique depends on:

• How badly damaged or rounded-off the socket is
• The equipment and location of the screw
• Available time and tools
• Whether the screw needs to be reused or not

Vice grips or pliers may work for screws with some intact edges remaining in the socket. Severely rounded internal sockets will require screw extractors, drilling, Dremel cutting, or epoxy fill methods. Extractors provide the cleanest removal option if the screw does not need reuse. Drilling, rotary tools, and glues are more destructive if salvaging the screw is preferred.

The surrounding material is also a factor. Drilling works well on softer woods or plastics but risks damage to metal parts. Test options gently in inconspicuous spots first when working on sensitive equipment. In many cases it takes trying more than one technique to find what works best for freeing up the stuck fastener.

Conclusion

Stripped Allen screw heads are certainly annoying but solvable with the right approach. Before attempting removal, assess the extent of socket damage and equipment involved. Have proper tools on hand like vice grips, extractors, carbide drill bits, Dremel, adhesives, and Allen wrenches. Work methodically applying gradual inward pressure with each technique to avoid collateral damage. With patience and care, you can successfully remove the stripped fastener, then take steps like using proper torque, lubrication, and wrench fitting to prevent future issues. Stuck Allen screws don’t stand a chance against these proven extraction methods.