How do you remove an Allen screw without an Allen key?

Removing an Allen screw without the proper Allen key can be challenging, but there are a few methods you can try to get the job done. An Allen screw, also known as a hex screw or Allen bolt, has a hexagonal socket in the head which requires an Allen key (also called a hex key) to loosen or tighten. If you don’t have the right size Allen key, don’t worry – with some determination and the right tools, you can still remove the screw.

Why Remove an Allen Screw Without the Proper Allen Key?

There are a few reasons you may need to remove an Allen screw without having the matching Allen key:

• You lost or misplaced the correct Allen key
• The previous owner or installer used a non-standard Allen key size
• You don’t have a full set of Allen keys to find the right size
• You need to remove the screw in an emergency situation

While having the proper Allen key size makes the job much easier, you can still get an Allen screw out without it using some simple tricks and alternative tools. The difficulty will depend on how tightly the screw was installed originally.

Can You Damage an Allen Screw by Removing it Improperly?

Attempting to remove an Allen screw without the matching Allen key size can potentially damage the screw, especially if a lot of force is used trying to turn the screw head. Here are some ways an Allen screw can become damaged:

• Stripping the hex socket – A tool that does not properly fit the socket size may strip out the shape of the socket making it more difficult to remove.
• Rounded out socket – An improper tool used with force can wear down and round out the distinct hexagon shape.
• Shearing off the head – Too much torque on the screw head without the proper Allen key could potentially shear off the entire head.
• Cracking the screw – Poor fitting tools may crack the metal of the screw head or threads.

To avoid damage when improvising tools, be cautious of using excessive force. Turn the screw in slow, controlled movements and stop if you encounter a lot of resistance.

Can You Remove an Allen Screw With a Screwdriver?

A regular flathead or Phillips head screwdriver will not grip an Allen screw well enough to provide sufficient turning force to loosen it in most cases. However, a screwdriver can be used to remove an Allen screw in some situations:

• If the Allen screw has become rounded or stripped, a flathead screwdriver may get enough grip to turn it.
• Use a hammer to carefully tap a flathead screwdriver into the screw socket to make a new grip.
• Try a Phillips head screwdriver if it fits snugly into rounded Allen screw corners.
• Alternate tapping a screwdriver into different corners of the socket to slowly turn the screw.

A screwdriver alone often does not have enough leverage for a tightly installed Allen screw. But it may work if the screw is already loosened or damaged.

Other Allen Key Substitutes to Try

While an Allen key/hex key is the proper tool made to fit Allen screw heads, there are some other common items you can substitute in a pinch:

TORX Drivers

TORX drivers, also known as star drivers, are six-pointed tools used on TORX screws. The pointed shape allows TORX drivers to fit into Allen screw sockets for improved traction. Use a TORX bit that closely matches the size of the Allen screw – T8, T10, etc. Apply steady pressure and turn slowly to avoid stripping the socket.

Hex Nuts/Bolts

Fitting an appropriate sized hex nut or bolt into the Allen screw’s socket can allow you to turn the screw. Tap gently to wedge the nut in place, then twist – the six points grip the socket better than a flathead screwdriver. Nuts and bolts allow for better torque versus makeshift tools.

Allen Wrenches

Use an Allen wrench (or hex wrench) that is close to the correct size if you don’t have the exact one. The closest size Allen will fit better than makeshift screwdrivers. Turn slowly and avoid stripping the socket. If you have a set of metric and imperial Allen keys, try both sizes.

Spoke Wrenches

Bicycle spoke wrenches have a hex shape that fits many Allen screw head sizes. Find one that closely matches and carefully turn the screw to avoid rounding. The long handle of the spoke wrench can provide good leverage.

Nail File/Emory Board

A metal nail file or emery board can be filed to fit into small Allen screw heads. Shape the end to create a makeshift Allen key, then slowly turn the screw once wedged into the socket. The metal file is stronger than an improvised plastic tool.

Tips for Removing Allen Screws Without the Key

Here are some helpful tips when attempting to extract an Allen screw without the proper Allen key size:

• Use penetrating oil or WD-40 to lubricate the screw threads first if corroded.
• Cut a rubber band and place it between the screw and your tool for better grip.
• Push firmly into the socket and turn slowly to avoid rounding off the head.
• Don’t force tools that don’t fit or overtighten and risk shearing the screw head.
• Use multiple tools if one slips – alternate between a TORX bit, hex nut, flathead, etc.
• Clamp vice grips or locking pliers on the exposed screw shaft for leverage.
• Place a block of wood against the threads and tap with a hammer if stuck.

Power Tools to Remove Stuck Allen Screws

Power drills, grinders, and cutting tools allow you to access and remove stubborn or seized Allen screws when improvised hand tools fail. Note that these methods will damage the screw head.

Drill Out the Screw Head

Use a drill bit slightly larger than the screw shaft to drill into the Allen screw head, removing the head completely. The remaining shaft can then be easily unthreaded. This method damages the head of the screw but preserves the threads.

Use an Angle Grinder

Carefully cut a slot across the screw head with an abrasive cut-off wheel on an angle grinder. This allows you to use a flathead screwdriver to remove the screw. Take care not to cut too deeply.

Cut the Screw With a Dremel

Use a Dremel rotary tool with a cut-off wheel to slice into the Allen screw head. Make two cuts opposite each other across the head to create a slot for a flathead screwdriver. Be cautious not to cut too deeply.

Extractor Tool

An extractor tool has tapered flutes that grip down into the metal as you twist it into the screw head. Once wedged in the extractor’s teeth grip the screw so you can turn counter-clockwise and remove it. This damages the head but removes even stubborn screws.

Alternative Solutions for Removing Stuck Allen Screws

If you are unable to remove the stuck or stripped Allen screw with improvised tools, there are a few options to completely remove the screw:

Cut Off the Screw Head

Use a Dremel or hacksaw to cut off the Allen screw head, leaving just the threaded shaft. With the head removed, the rest of the screw can then be unscrewed or pulled out of the hole. Be careful not to damage nearby material when cutting.

Drill Out the Entire Screw

For screws that are hollow or soft metal, use a drill bit slightly wider than the shaft to drill down through the head into the screw body and threads. Keep drilling until the entire screw is removed from the hole. This completely destroys the screw but removes it fully.

Helicoil Insert

If you must leave the damaged screw in place, you can insert a helicoil threaded insert next to it. The helicoil creates new machine threads so you can install a new matching screw nearby. This leaves the old Allen screw stuck in place.

Just Remove the Material

As a last resort, you may need to remove the object or material the Allen screw is threaded into. This could require cutting welds, unbolting adjacent parts, or completely replacing panels. If the screw is not critical it may be easier to remove it with the surrounding material.

Preventing Stuck Allen Screws

To avoid being in a situation where you need to remove an Allen screw without the right Allen key, follow these best practices:

• Always use the correctly sized Allen key – never force a mismatched tool into the socket.
• Regularly tighten and loosen the screw during long-term use to prevent seizing up.
• Lubricate screws periodically with penetrating oil to prevent corrosion.
• Start screws by hand with the Allen key before using a powered driver.
• Take care not to overtighten Allen screws – use torque limiting drivers if possible.
• Use anti-seize lubricant on stainless steel Allen screws to deter galling and seizing.

Conclusion

Removing an Allen screw without the proper fitting Allen key is certainly not ideal and risks damaging the screw. However in some circumstances it can be achieved through clever improvising and tool substitutions. Using torx bits, hex nuts, modified screwdrivers, spoke wrenches, and other shaped objects you can often get enough purchase to slowly back a screw out. Penetrating lubricants also help loosen stuck screws.

For stubborn or seized Allen screws, power tools like drills, Dremels, and grinders allow you to cut away and remove the screw head or body when improvised hand tools fail. But ultimately, having the right Allen key size matching the screw will make removal vastly easier and minimize the risk of damage.