When wrenching on your Jeep, truck, or SUV, one universal truth seems to always apply. At some point throughout the day, something will go awry. When this occurs, frustration builds, excess time is expended, and more often than not, a few choice words are said. However, one must still handle the task at hand, keeping a level head to circumvent the issue that has arisen.
Few situations illustrate this exact scenario quite as aptly as that of being forced to contend with a stripped or rounded bolt. At times, stubborn bolts can give even the most experienced of mechanics a run for their money, and every trick of the trade must be employed in order to achieve a meaningful resolution.
However, the question still remains, just how does one go about removing a stripped or rounded bolt?
What Is A Stripped Bolt?
If you have yet to encounter a stripped or rounded-off bolt, consider yourself among the fortunate minority. Finding yourself in such a predicament can be more than a little taxing on your blood pressure, and possessing an innate sense of creativity is a must in order to emerge victorious.
When someone says that a bolt is stripped, they are most commonly referring to a condition where a bolt’s hex-shaped head has taken on a rounded profile, to which a traditional wrench or socket will no longer fit. This presents a problem, as it is seemingly impossible to remove a bolt without being able to grip its head to impart rotational force.
When dealing with a stripped bolt, a wrench or socket will simply turn in place with minimal pressure, since there are no longer any defined corners to which such tools can grab. In the bulk of cases, one can feel as a wrench or socket “slips” across what little remains of the bolt head’s once-pronounced corners.
What Causes A Bolt Head To Strip?
A bolt’s head can round off for a number of reasons, or alternatively, as the culmination of several factors. Perhaps the most common of these reasons is that of attempting to use an incorrectly sized ratchet and socket, or wrench, for bolt removal.
This occurs most frequently when a standard-sized socket or wrench is used while removing a metric bolt, or vice versa. Though it might seem as if this incorrectly-sized tool fits the fastener in question, just enough free play remains to prevent a solid grip on the head of the bolt, thereby allowing the malleable metal head to round off when force is applied.
Rust and corrosion can also play a significant role in causing a bolt head or nut to round out. It is quite common for a heavily-rusted bolt head or nut to round out or strip, even when using the proper size wrench. Problems of this nature tend to be significantly more common in northern climates, where salt and calcium-chloride are frequently used as de-icing agents during periods of wintry precipitation.
How To Remove A Stripped Bolt
When a bolt head or nut is stripped or rounded off, one must formulate a game plan. Performing such a task is far from a textbook operation by any stretch of the imagination, as no two sets of circumstances are exactly the same. While one particular case might allow plenty of room in which to work, this is often not the case. More often than not, such occurrences take place within tight confines, where available work space is heavily restricted.
Assessing the situation at hand is key, as doing so allows you to choose the best possible route for extraction. The size of a bolt, its condition, and the specific torque to which it is tightened are all valid considerations when choosing how to proceed. While one particular approach might work perfectly when dealing with small fasteners torqued to minimal specifications, larger or significantly tighter bolts can potentially warrant an alternative response.
The following are the top methods for removing a stripped nut or bolt.
Reshape Edges
If a bolt is only slightly stripped, one can often get away with simply filing the edges of the bolt’s head back into a squared, true form. While this will almost certainly take a little time and an ample dose of patience, the reward is well worth any work put in. Once the compromised bolt has been restored to its prior shape, a socket wrench can be used to resume removal.
In the event that the use of a file has not sufficiently refinished the bolt’s head, a grinder can be used to quickly reshape the troubled fastener. However, care should be taken to avoid removing too much material from the bolt or nut in question.
Use an Extractor
The use of a specialty extractor socket is by far the easiest way to remove a stripped bolt. Sockets of this nature are offered in various sizes and feature spiraled ridges within their recesses. When turned with a ratchet, these ridges bite into the head of a stripped bolt, providing a solid grip. Once this contact has been made, the stripped bolt or nut can be removed in the same manner as would be the case if not in poor condition.
It is also worth mentioning that not all bolt extractor sets are created equally. Lower quality extractors have a tendency to slip, causing further damage to the already degraded bolt. Finding success when using this method begins with selecting only quality extractors for use, such as those made by Irwin. Before beginning the extraction process, it can also be quite helpful to liberally spray the offending bolt or nut with a premium penetrating oil, such as Kroil or PB Blaster.
Use Vice Grips or Locking Pliers
The use of hand tools such as vice grips or locking pliers can also be helpful when attempting to extract stripped nuts and bolts. Doing so involves clamping down tightly on the stripped fastener and slowly, yet steadily, twisting it. When employing this method of removal, it is absolutely essential to maintain a tight grip on the bolt head or nut that is being removed. If a solid grip is not maintained, further rounding of the stripped fastener will occur.
While this method can be quite effective when removing smaller fasteners that are torqued to minimal standards, substantially greater difficulty is to be expected when removing large or otherwise seized bolts. In any event, the use of a quality penetrant is always advisable prior to the onset of the extraction process.
Use a Hammer and Chisel
One can also use a hammer and chisel to remove a stripped or rounded bolt. In order to do so, a chisel must be driven into the edge of a bolt's head by way of a swift blow delivered from a hammer. With each strike of the hammer, the bolt’s head is turned slightly in a counterclockwise fashion. Doing so effectively loosens the stripped or stuck bolt, saving you from being forced to take any further measures.
When striking a bolt head with a hammer and chisel, the chisel’s point of impact is immensely important. A blow to the center segment of a fastener is of little value. Instead, aim for the outer edge of a bolt head or nut’s profile, as this “walks” a bolt free from its location. Direct your blows in a manner that replicates an attempt to cut away a specific corner of a bolt head. This is the point at which maximum rotational force is rendered. Alternatively, an air hammer and dull chisel bit can be used on the heads of larger fasteners in a similar manner.
Turn A Bolt Into A Screw
At times, a rounded off or stripped bolt can be removed like a large screw. This process begins by cutting an elongated slot in the bolt’s head, to which a flathead screwdriver can be fitted. A secondary cut can also be made in a perpendicular fashion to the initial cut. This will allow the use of a Phillips screwdriver should the need arise.
By turning a screwdriver in a slow yet steady fashion, stubborn bolts can often be removed. At this point, if the previously-mentioned cuts are true in angle and deep enough to present a solid hold, a handheld impact driver can be used to impose additional force for removal.
Weld On Additional Head
Yet another method of extracting a stripped bolt is to weld a new head in place atop that which has been damaged. This can be done by cutting the head off of a spare bolt and then using a welder to secure it to the stripped bolt that is to be removed. With the fresh bolt head in place, removal should be no more difficult than when removing any other bolt in respectable shape.
When choosing which size donor bolt to use, it is invaluable to select that which features a head that is equal to or slightly larger than the bolt head which is being removed. This allows a socket to be positioned over the fresh bolt head, without coming into contact with the stripped bolt head below. Although typically bulkier than a bolt head, a nut of the appropriate size can also be welded atop a stripped bolt in a similar manner.
Apply Heat
If none of the prior steps have proven successful, the most efficient way to proceed is by applying heat to the affected area. Heat causes the metal to rapidly expand, and heating the area directly surrounding a stubborn bolt’s location can loosen it substantially. This can be done one of two ways: with a handheld propane torch or an oxy-acetylene torch.
Once the area surrounding a bolt has been heated, a rapid cooling agent, such as Freeze-Off can be used in order to cause the bolt to contract. The two opposing forces of heating and cooling are, more often than not, the perfect combination for unseizing the most reluctant of fasteners.
Drill It Out
At times, even the best-laid plans fall short, and those made when attempting to remove a stripped or rounded bolt are no exception. When your subsequent removal efforts fall short and no other viable methods for extraction remain, there is little else one can do but drill out the offending bolt. However, doing so should be done only as a last resort.
Before drilling, care should be taken to mark the center of your bolt. The most viable method of doing so is to make a small indention with the use of a center punch and hammer. You will then drill down through the center of this bolt while keeping a level of awareness as to the angle at which you proceed. Begin drilling with the smallest drill bit at your disposal, increasing gradually in size from one bit to the next.
You will eventually begin to notice that the outer diameter of the hole that you are drilling reaches the bolt’s threads. At this point, the remainder of the bolt should be free enough to unthread by hand. Upon the bolt’s removal, it is of vast importance to inspect the threads of the hole into which the bolt was threaded.
If any damage is observed, it is imperative to make any necessary repairs prior to the installation of a new bolt as a replacement. A properly-sized tap can be used in many cases to rectify any damage which has occurred. However, when these threads have been badly damaged, it becomes necessary to drill out any remaining threads and re-tap the point of mount to the next applicable size.
Dealing With Stripped Screws
Aside from being forced to deal with the occasional stripped bolt, it is also common for the avid DIY mechanic to encounter stripped out screws. While this scenario can also be quite troubling to contend with, there are several ways to remedy such a predicament. The following removal tactics can be used on all screw types, including those with flathead, Phillips, hex, and Torx heads.
Use a Left-Handed Drill Bit
In many cases, a stripped screw can be removed with a left-handed drill bit. These specialty bits are designed to “grab” as they rotate and will often unthread a troublesome screw when in use. The use of bits of this nature is an excellent first step when attempting to remove a stripped screw, as they prepare such a screw for the next most potent means of removal, even if it is not successfully extracted during this step.
Use an Easy-Out (Screw Extractor)
If a stripped screw is not successfully removed with the use of a left-handed drill bit, the next step of the removal process is to use an easy-out. Easy-outs, or screw extractors as they are known alternatively, are small bit-like tools that are intended to grip the inside lip of a seized screw that has been drilled. These tools come in two main types: straight and spiral fluted. One can experiment between the use of each type of extractor to find what works most applicably. Simply tap the extractor into your previously-drilled hole and turn in a counterclockwise fashion.
Drill It Out
In the event that the above-mentioned methods of removal have been employed to no avail, a stripped screw can be drilled out in its entirety in an identical manner to a bolt. Simply start this process with a small drill bit, working up gradually in size. Upon reaching the outer diameter of the affected screw, simply spin it free from its bore with a set of quality pliers. It is also imperative to analyze the threads of the borehole into which the stripped screw was threaded. If any damage is observed, the use of a properly-sized tap will be necessary.