A stuck screw can prove to be the ultimate nuisance, the proverbial "thorn in one's side" as craftsmen strive to complete a project or repair. Stuck and stubborn screws are generally caused by rust and corrosion that accumulates and sticks around the screw's body. To release the screw, you must break it loose from the corrosion that binds it. To achieve this breakaway, try these five sure-fire extraction methods and you should have that stuck screw un-stuck in no time.
1.) Chemical Removal: Chemical removal methods are the first, most gentle techniques to try. To dissolve the binding corrosion you can apply a number of easily accessible products: lemon juice, hydrogen peroxide, and even Coke or Pepsi can loosen a stuck screw. Any anti-corrosive solution works better when left to soak into the screw-hole, because of this, even if the chemical doesn't release the screw, it softens it up for the next removal step(s). If you tap the screw while applying rust remover, it may help the chemical to penetrate further into the screw-hole releasing more of the screw. Once you've let your solution set into the screw, attempt to loosen it once more. Remember not to use a solution that could stain or damage the material housing your frozen screw.
2.) By Force/Impact: Before beginning this process be certain you have the correct sized screwdriver. A wrong sized screwdriver can strip the head off your frozen screw and amplifty the supreme annoyance of screw extraction. If you can move the screw at all try to tighten it - in doing so you may break the screw free from the corrosion holding it in place. If you can't move the screw but its head is slightly elevated, you may be able to grip, and turn the screw with vice grips or pliers. If, however, the screw's head is not sticking up, you may try inserting the screwdriver in the the screw's head slots. Lock your pliers or vice grips to the top of the screwdriver shaft, and while keeping downward pressure on the screwdriver, and using the vice grips as leverage, try turning the screw. This additional leverage/force may break it free. You may also try hitting the screwdriver with a hammer (while the screwdriver is inserted into the screw's head). Remember to do this lightly so as to not destroy the tip of your screwdriver. If you can, also try hitting the screwdriver while turning it - this combination of impact and rotation should break the screw free from adhesion.
3.) Heat/Cold: Before using temperature extraction methods, be certain the material housing the screw can withstand temperature changes. That said, you can use a propane or butane torch to heat and consequently expand the screw. You can also use a soldering iron or even a hot glue gun (without glue) to heat up a frozen screw. The expansion should allow you joggle and reverse the screw free. If the material around the screw can not tolerate heat, cold temperatures, although less effective, may work for you. Keep ice on the screw's head - if accessible, dry ice is most effective. When the screw is sufficiently cold try turning again. Note: If you choose to heat up your screw - don't apply lubricating oils (as they are flammable) to the screw until it has entirely cooled. You may need to repeat heat and cold cycles several times to break the screw loose. Always be mindful when using temperature extraction methods - both can cause severe burns when not careful.
4.) Destruction: If you absolutely have to get the screw out, and it still has not budged, you can attempt to destroy the screw. These methods are generally reserved for last resorts and craftsmen must be mindful to keep the screw hole intact. If the screw hole becomes damaged it is much more difficult to replace that stuck, rusted, and stubborn screw. First: place a steel punch or small chisel slightly off-center in the screw's head-slots. Repeatedly hit (with a hammer) the top of the punch or chisel counter-clockwise (remember, righty tighty - lefty loosy). Several impacts should effectively loosen the screw. You may also try drilling out the screw. When drilling out a screw, keep your drill bit dead-center. If you have access to left handed drill bits these put more turning pressure on the stuck screw as it turns. Eventually the screw should begin to turn and release.
5.) Drastic Measures: These are definitely last resorts, however, screws with a totally stripped or broken head may be impossible to remove without a "screw extractor." A screw extractor is a marvelous little device (only about $5 - $10) with a square head and reverse tapered cutting screw threads on the other end. The square head is built to be fastened to a T Handle but also works with an adjustable wrench or vice grips. After a pilot hole has been pre-drilled into the stuck screw, the counter-clockwise threads are designed to screw backward into the screw's body. The extractor digs into the damaged screw, begins to turn it, and ,at last, releases it from the grasps of corrosion. Be extremely cautious not to break-off the screw extractor inside your stuck screw. If this happens, you're basically, well... stuck. If a screw extractor can't get the job done, and you are now more hell-bent than ever to get that screw out, there is one last option. Spark erosion. Spark erosion, or electrical discharge machining is a technique that utilizes rapid repetitions of electrical discharge to disintegrate metals. This method effectively melts, or dissolves the screw while leaving the screw hole and surrounding materials unharmed and intact. Spark erosion machines are truly impressive, but are also pretty difficult to gain access to. In order to utilize spark erosion you must find a service that provides this type of machining. In the long run it may not be worth the hassle. Keep trying, show that screw who's the boss, and persistence will prove the most effective method for success.
Removing stuck screws can be an immeasurable hassle, but one of these methods is bound to loosen that pesky screw. Good luck, and always be cautious!