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Try these quick and easy techniques before calling a pro
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A bolt is a piece of hardware typically used to hold two or more pieces of lumber in place. Unfortunately, during construction, it is possible for a bolt to break. While this is unusual, inexperienced or rushed work increases the likelihood of it happening. Learning how to remove a broken bolt is essential for the completion of construction or home improvement projects.

Method 1
Method 1 of 2:

Using an Extracting Kit

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  1. Using a hammer, mark the center of the broken bolt with a center punch. This will help you drill into the center of the bolt as closely as possible, putting you at less risk of damaging the threads of the broken bolt. [1]
  2. Watermark wikiHow to Remove a Broken Bolt
    [2] A left-handed drill bit is threaded in the opposite direction, so the reverse setting on your drill is what will actually drive in the bit. You want to use a left-handed bit because it will torque in the opposite direction as the broken bolt, which will stop the bolt from being driven in tighter. [3]
    • If you’re lucky, the left-handed bit will grab and unscrew the bolt enough by itself for you to grab the bolt with a pair of vice grips or channel locks and finish removing it from there.
    • Make sure you use the appropriate size drill bit. The bits in the extracting kit should have a table letting you know what size to use based on the size of the bolt you need to remove. Using too big a bit will risk damaging the threads on the bolt, and using too small a bit will require a smaller, weaker extractor with a higher risk of breaking off during the process.
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  3. Watermark wikiHow to Remove a Broken Bolt
    Based on the type of extracting kit you purchased, the extracting bit will have a tapered, left-handed bit at one end and either a hex head or a T-handle head at the other. Since the extractor is also a left-handed bit, it will also work into the broken bolt with a counterclockwise movement. [4]
    • Since the extractor is tapered, you should initially tap it into place with your hammer before switching to a socket or T-handle.
  4. Watermark wikiHow to Remove a Broken Bolt
    As you continue to tighten in the extractor , the tapered end will catch and the torque will work to loosen the bolt once the extracting bit is snug.
    • Continue turning the extracting tool counterclockwise until the broken bolt has been completely removed from the surface in which it was embedded.
    • Be sure to take your time during this process to prevent excessive damage to either the bolt or the item from which you are removing it. You also want to work the extractor as gently as possible because they are made of hardened steel, and a broken off extractor will be even more difficult to drill out.
  5. Watermark wikiHow to Remove a Broken Bolt
    During the bolt-removal process, it is likely that small amounts of metal fillings will have come off of the bolt. If you plan to replace the broken bolt with a new one, it is important to first remove all of these fillings and shaving. You can most easily accomplish this with either a magnet or compressed air. [5]
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Method 2
Method 2 of 2:

Using a Welding Technique

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  1. Watermark wikiHow to Remove a Broken Bolt
    Just like you would using the extractor, you want to use a hammer and a center punch to mark the center of the bolt.
  2. Watermark wikiHow to Remove a Broken Bolt
    Drill out the center of the bolt. Use a bit that is roughly one-quarter the diameter of the bolt and drill it out. [6]
    • This method of extraction is typically reserved for bolts that are too corroded to be removed with an extractor, so you do not need to worry as much about tightening the bolt while drilling it out with a right-handed bit, but using a left-handed bit can’t hurt.
  3. With any threading the bolt still has exposed, tighten a hex nut onto it. You want to attach the nut firmly, but back it off around half a turn, so that it’s not completely flush with the surface into which the bolt is embedded. [7]
  4. Watermark wikiHow to Remove a Broken Bolt
    Weld the bolt to the nut. This is a quick weld, but you do not want this to be your first attempt at welding. If you need to, have an experienced friend complete the weld, or you can always practice on something else first.
    • Be especially careful if the surface into which the broken bolt is embedded is one that will melt to the steel bolt or nut. Because of this, this method works best against a surface such as aluminum, which does not easily weld to steel.
  5. Watermark wikiHow to Remove a Broken Bolt
    After the weld has had time to cool, the hex nut has essentially been welded into place as the new head of the bolt and can probably be removed with a socket or a wrench.
    • The weld is strong, but it will not be unbreakable. For especially corroded bolts, the nut may have to be welded back in place more than once.
    • In order to break the corrosion bonds, try slowly working the bolt back and forth initially. Once it starts to loosen, continue working both directions but more so counterclockwise, so you can begin removing it entirely. [8]
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      Warnings

      • Go slow when using an extractor and don’t overpower it. Breaking an extractor off in a broken bolt requires an even stronger material than the hardened steel of the extractor to remove.
      • Take every necessary precaution if attempting the welding method, including a welding jacket, welding helmet, gloves, pants without cuffs, and boots.
      • Wear eye protection when drilling out the broken bolt since the process will create metal shavings.
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      Things You'll Need

      • Power drill
      • Left-handed drill bit
      • Extracting bit
      • T-handle
      • Vise grip
      • Magnet
      • Hammer
      • Center Punch
      • Compressed air
      • Hex nut
      • Welder
      • Welding helmet
      • Welding jacket
      • Gloves
      • Safety glasses

      About This Article

      Article Summary X

      If you want to remove a broken bolt without welding, center punch the broken bolt, then drill a pilot hole into the center of it with a left-handed drill bit. Next, put an extracting bit into the hole you just drilled and rotate it counter-clockwise until it tightens and unscrews the bolt. Finally, remove any metal filings with a magnet or compressed air before putting a new bolt in the hole. Keep reading to learn how to remove a broken bolt by welding a nut onto it!

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      Reader Success Stories

      • Anonymous

        Feb 7

        "- The drill bit shown on stage 2 seems to be right-handed, not lef.- Stage 4 speaks of extractor bit, but the video ..." more
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