Three Ways to Remove a Broken or Stripped Screw
Three ways to extract a broken and stripped screw
I had eight stripped and broken screws that were rusted and completely stuck that I need to remove to replace a part. I started with trying to find a screwdriver that fit the remaining grooves as well as possible, but as soon as I twisted, the screw was completely stripped.
Start by Applying a Penetrating Liquid
Often times a screw is rusted and the corrosion bonds between the screw and what it's screwed into. Using a penetrating oil like liquid wrench will break down the rust and help loosen the screw.
If you are trying to remove a stripped screw that is rusted, applying a penetrating oil should be the first step. Other types of chemicals can be used to break down rust and clean screws. I've had good success with Pepsi and Coke. They are both high in acid. Also, lemon juice will work. Pour the liquid on the screw and let it sit. It often takes multiple applications for the liquid to eat its way through the grooves of the screw. I've also had success using Easy Oven Off on stuck screws. I just spray it on liberally and then come back the next day.
Extract a Screw with Pliers
The first screws I was able to remove with a pair of pliers. From the top of the screw, I clamped the pliers tightly around the sides of the screw head and twisted. Slowly I was able to pull the screw out. This technique works best when the screw still has grooves, but the head is broken off so that a screwdriver won't work.
Removing a Screw with Pliers When the Head Breaks OffClick thumbnail to view full-size
Using a Screw Extractor Kit
When I couldn't get the pliers around the head, I tried to use a screw extractor kit. Using the largest size I could, I put the extractor in my electric drill and reversed the screw out. The extractor is made of extremely hard metal. I had to press down on the screw with all my force to dig the extractor grooves into the stripped out screw head and then I applied a low amount of power to the drill. If you go to quickly, the screw will be completely destroyed.
The local hardware store should carry a kit or individual bits. They range from $3 for a single bit to $60 for a high-end kit.
The screw extractor worked on a few screws, but a few others were too tough.
Screw extractors work best when the threads of the screw are stripped and the head of the screw is broken off flush to the surface so that it's impossible to grip with pliers.
Screw Extractor Photo
Drill the Screw Out with Metal Drill Bits
Some screws won't come out with pliers or a screw extractor kit. For the third option and last resort, I used drill bits for metal. Pushing the bit straight down on the head of the screw I hollowed out the screw until the screw was destroyed.
I also used the drill bits to weaken the head of the screw and pulled the head off. Then I used pliers to twist the remaining portion out when enough of the screw was exposed.
A Few Other Techniques I Tried to Remove the Screws
The screws were rusty and caked in oil so I tried to clean them with WD40. That seemed to help when I used the screw extractor kit.
I also tried heating the screws with a small torch. That seemed to make it easier to drill them out when they were hot.
I spent a good four hours removing eight screws with these techniques. They aren't pretty, but they work.