Threads are present in practically every manufactured part. However, overuse or poor installation techniques can cause permanent damage to a thread. Unfortunately there is no easy fix, and you may have to use hardware to salvage the thread. As such, would like to share a few of our tips on how to fix a stripped thread.
Option 1: Re-tap the Hole
If the hole has been lightly damaged you may be able to re-chase the thread. Simply re-run a fresh, clean tap through the damaged hole. This is typically done by feeding the tap in from the bottom of the part and chasing the thread through the damaged region. Unfortunately this option will only work if the thread is lightly damaged. This may also fix a thread if there is plating build up or if the thread is dull from overuse. For a detailed perspective on how to chase a tapped hole please read our article found here.
Option 2: Insert a Helicoil
If the thread is cross threaded or shows significant damaged, then the thread will need to be replaced. The first option we recommend for fixing a stripped thread is a helicoil. Please reference our article on how to install a helicoil here. Helicoils are a great option since they can be installed from either end of a tapped hole and they are relatively inexpensive. However, they do require special STI taps and tangs can get lost within your part. Tangless helicoils are always an option, but they are more expensive and less readily available. We recommend the following suppliers for helicoils:
For a size guide please see the chart below:
Option 3: Insert a key-insert
If you are in need of a heavy thread replacement or if you expect a thread to be going in and out a lot, we recommend utilizing a key-insert. Please reference our article on how to install a key-insert here. Key inserts require readily available taps and provide a strong, sturdy solution for stripped thread repair. However, they do require a few more tools and you may have to enlarge the hole by a significant amount.