How to Drill Out a Grade 8 Bolt

When a grade 8 bolt gets stuck in one of your vehicle's components and you've stripped the bolt head off, there is only one way to remove it: you must drill out the bolt. Because grade 8 bolts are extremely hard, you will need a metal cutting drill bit and a drill capable of spinning at 3,000 RPM.

Things You'll Need

  • Drill capable of at least 3,000 RPM
  • Steel-cutting drill bit
  • Select the right sized drill bit: the drill bit must be just slightly smaller than the bolt you are drilling to avoid damage to the internal threads on the component you are drilling into.

  • Place the drill bit in the center of the bolt.

  • Start drilling on a slow speed to create a groove in the center of the bolt.

  • Increase speed to the highest speed once a groove has been started. Drill all the way through the bolt until it is removed. You may need to periodically remove some bolt fragments from the area you are drilling.