
How to Remove a Stripped Screw
from wikiHow - The How to Manual That You Can EditSometimes the head of a screw becomes worn and becomes difficult to remove due to slippage between the screw head and the screwdriver bit. This how-to discusses how to get these difficult-to-remove screws out of whatever it is that they have gotten stuck in.
Steps
- Avoid making the problem
worse. If the tool you are using is slipping, stop using it immediately.
Further slippage will only continue to wear down the screw head and make
it harder to remove. Definitely be sure you are going in the correct
direction for removal, which is usually--but not always--counterclockwise
("righty tighty, lefty loosy"). Pressing down hard as you are
unscrewing will help prevent slippage.
- Use a manual screwdriver
rather than a power drill. You will be able to put more pressure on the
back of the screwdriver (to increase friction) and to go more slowly. Not
all drills are strong enough to exert as much torque as you need to remove
a recalcitrant screw. Some chuckless drills will actually lose their grip
on the screwdriver bit if you put too much torque on them (especially in
the reverse direction).
- Get more torque with a socket
wrench. If you need a lot of torque because you are hurting your hand or
you are not getting results, the best tool is a socket wrench, a common
part of many professional screwdriver sets. This allows you to get 6
inches or more of lever arm rather than the half-inch or so a screwdriver
handle produces. This greatly increases the amount of torque you can put
on the screw for a given amount of hand pressure.
- Use a screw extractor. The
right tool for the job, assuming the screw head is worn but intact, is
called a "screw extractor". This is essentially a screwdriver or
screwdriver bit which has strong, rough metal threads right on the tip.
These are intended to burrow into the metal of the screw head and get
stuck there so you can put some torque on it.
- Use a screw extractor
like a normal screwdriver to remove the screw. Be sure to go slowly, and
press down hard enough to prevent slippage and engage the burrowing
threads.
- If the screw extractor
cant get a grip, you may need to drill a small hole into the screw head.
You will need a drill bit that is designed for drilling metal; a
wood-drilling bit wont survive. Be careful! If you drill too far, you
will destroy the head entirely or make it fragile enough that it will
snap off, making it even harder to get the screw out. Given the nature of
what you are drilling, pieces of metal may suddenly come flying out of
the assembly, so wear eye protection!
- There is also a
multi-spline type of screw extractor. The multi-spline extractor is like
a hex nut with splines instead of threads on the inner bore. The
multi-spline extractor fits over the head of the screw and over any
projecting stud. The internal splines (teeth) engage the rounded head of
the screw. Tap the extractor gently into place and turn it with a socket
wrench. The multi-spline extractor is good for Torx and Allen head screws
if the cylindrical body of the Allen screw is exposed. The multi-spline
extractor is typically described as "Bolt extractor 5-piece
set".
- Try a different screwdriver.
If you do not have a screw extractor and do not want to try to get one
just yet, you can try to use a different screwdriver or screwdriver bit. A
screwdriver with a bigger head may help. Some screw heads can accept
either a slot or a cross-head (e.g. Phillips) screwdriver. You may have
some luck trying the other kind. If you have them in your screwdriver set,
you might also try a Robertson (square), Allen (hexagonal), or Torx (six-pointed
star) bit, depending on the shape of the hole you have. You may have some
luck if you experiment with sizes.
- Tapping the screwdriver into
place with a hammer may be helpful. Tap it with a hammer, but be careful
and gentle as excessive force will destroy or remove the head of the
screw.
- Drill out the entire screw as
a last resort, and only if the screw is holding together metal objects. If
all else fails, it is possible to drill out the existing screw with a
power drill and bit of the same size as the screws shaft. This will most
likely remove the existing thread. Possible solutions at this point:
- Replace old screw with
a self-tapping (thread-forming) screw of slightly larger size.
- Use a nut and bolt
instead. If desired, weld the nut to one of the metal objects to create a
stationary, threaded mount.
- If the screw was large
enough, install a HeliCoil insert.
- Often placing a broad, flat
rubber band between the screw and the screwdriver will yield good results
if firm pressure and slow rotation is used. The rubber band acts to fill
in the space that the screwdriver cannot grip.
Video
- Use a screw extractor
like a normal screwdriver to remove the screw. Be sure to go slowly, and
press down hard enough to prevent slippage and engage the burrowing
threads.
- If the screw extractor
cant get a grip, you may need to drill a small hole into the screw head.
You will need a drill bit that is designed for drilling metal; a
wood-drilling bit wont survive. Be careful! If you drill too far, you
will destroy the head entirely or make it fragile enough that it will
snap off, making it even harder to get the screw out. Given the nature of
what you are drilling, pieces of metal may suddenly come flying out of
the assembly, so wear eye protection!
- There is also a
multi-spline type of screw extractor. The multi-spline extractor is like
a hex nut with splines instead of threads on the inner bore. The
multi-spline extractor fits over the head of the screw and over any
projecting stud. The internal splines (teeth) engage the rounded head of
the screw. Tap the extractor gently into place and turn it with a socket
wrench. The multi-spline extractor is good for Torx and Allen head screws
if the cylindrical body of the Allen screw is exposed. The multi-spline
extractor is typically described as "Bolt extractor 5-piece
set".
- Replace old screw with
a self-tapping (thread-forming) screw of slightly larger size.
- Use a nut and bolt
instead. If desired, weld the nut to one of the metal objects to create a
stationary, threaded mount.
- If the screw was large
enough, install a HeliCoil insert.
Learn how to remove a stripped screw using a screw
extractor.
Tips
- You might be lucky enough to
have a screw head (or exposed screw on the rear side of the piece) you can
grab with some pliers or a hex wrench.
- A stripped cross-head screw
can sometimes be extracted by using a hacksaw to saw a slot across the
center of the head. After the slot has been created a normal slot-head
screwdriver can be used to extract the screw.
- Try this simple
method:(explained for a star screw)
- (1) Hold & rotate
the screw driver using the dominant hand & guide the tip using the
other.
- (2) Without applying
any pressure rotate the driver in anti-clockwise direction, feeling the
traction for all the 4 possible configurations.
- (3) Keep going in
rounds until you feel the one with the maximum grip(after 1 full
rotation).
- (4) Stop & turn in
clockwise direction to achieve the configuration with maximum grip.
- (5) Now put all your
strength to push(concentrate more on this because,if you fail the head
gets worn out more)& rotate(anti-clockwise) the screw driver - If the
screw can be removed by a screw driver, this is your best chance
Warnings
- If you use a screw extractor,
it may get stuck to the worn screw and be very hard to remove. You might
not be able to use it again, but at least youve gotten your screw out.
- Power tools can be dangerous
and should only be used with adult supervision. Follow the manufacturers
instructions, and wear eye protection.
- Make sure the object you are
removing the screw from is well secured, that you have a tight grip on the
tool, and that if you slip, you wont get hurt. You may need to use a lot
of force, and you do not want that energy directed toward your body.
- Metal burrs caused by
stripped screws can cause injury or mechanical malfunctions.
- Welding is dangerous and
should only be performed by trained professionals.
Things You Will Need
- Screwdriver
- Screw extractor, screw
extractor bit, or screw extractor kit. $1-$20 in your local hardware
store.
- Socket wrench
- Power drill
- Metal-drilling drill bit
- Eye protection
- Work gloves
- Hammer
- Optional - professional
welder
Related wikiHows
- How to Fix a Stripped Screw Hole
- How to Read a Screw Thread Callout
- How to Hold
Small Screws Steadily on the Tip of a Screwdriver
- How to Reinstall Screws and Bolts
- How to Fix Sticky Drawers
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