How to Remove a Stripped Hex Bolt Head

By T.J. Black
Hex bolt and nut

Whether you like to work on cars, motorcycles or helicopters, there may come a time when you run into a stripped hex bolt. When this happens, you'll want to be able to remove it without wasting time you could be spending on other parts of your project. With the right tools, any mechanic can fix the problem quickly and inexpensively.

Find the hex driver that is one size larger than the stripped hex bolt head.

Place the hex driver over the head of the bolt.

Twist the hex driver to attempt to back out the hex bolt. The extra space will sometimes allow you to back out the bolt even with a stripped head.

Use a rotary tool and a cutting wheel to cut a slit in the top of the hex bolt head.

Place a flat-head screwdriver into the slit. If you prefer to use a Phillip's screwdriver, make sure you cut the cross slit to create the "X" shape.

Turn the screwdriver to back out the hex bolt.

Use a rotary tool and a cutting wheel to cut off the head of the bolt.

Position the rotary tool as close to the head as possible. If you leave enough of the thread, you may be able to use a pair of vise grips to back out the bolt.

Find a drill bit that will allow you to drill into the center of the bolt if you can't get a grip on the thread. You will want to base the size of the drill bit on the size of the screw extractor you plan to use.

Get a screw extractor kit with bits in the correct size for your hex bolt.

Work the screw extractor bit into the hole you drilled. Take your time with this step; any movement from side to side can break the bit.

Turn the screw bit extractor counterclockwise to work the bolt out.

Purchase a special tool designed to remove stripped bolts. These tools bite deeper into the metal as you turn, creating the torque needed to remove the bolt.

Heat the hex bolt head. This works for bolts securing non-aluminum surfaces.

Use a left-hand drill bit in place of screw extractor kit.

Weld a new head onto the bolt after you cut the stripped head off of it. Allow the weld to dry completely before you attempt to remove the bolt.

Tip

It may help to lubricate the stripped hex bolt head with penetration fluid before you attempt to remove it.

Warning

If you decide to use a rotary tool, keep in mind that it may cut into the surface around the head of the hex bolt.