A Guide to Thread Repair
Are you looking for a permanent solution to restore a defective thread to its nominal size? If so, then you've come to the right place. This article is designed to help you quickly repair defective threads in 5 simple steps, so read on to get the information you want.
Thread Repairing Tools
Causes of Thread Damage
Thread damage can occur due to a number of factors. Typically, thread damage is caused by incorrect fastener installation, use of incorrect bolt torque, breakage of the tap or fastener in the hole, or microscopic thread wear due to prolonged vibration during machining applications.
Thread Repair Kits
Thread repair kits allow for the removal of damaged threads in a hole and their replacement with new threads of the same size. Thread repair kits typically include a tap, twist drill, mounting handle, breakage tool, and thread insert, and a tap wrench may be required for thread repair. For your convenience, we offer different types of thread repair kits.
How do I repair a thread?
There are various methods of thread repair. If the external thread is damaged, it can usually be repaired by using a pitch gauge to determine the pitch and then running the appropriate thread file on it. If the damage to the threads is super small, the threads can be repaired by turning the nut up and down.
If the internal threads are damaged, re-turning the hole with a larger diameter thread tap is an option, provided there is room for a larger fastener. When creating a new, the larger threaded hole is not optimal or possible, the use of a thread repair tool is recommended.
Steps to repair threads
1. Drill out the damaged thread using the correct diameter drill bit.
2. Tap the hole with a tap to accept the threaded insert.
3. Drill the threaded insert into the hole and secure it below the surface of the part.
4. Unscrew the insertion tool to release the torque, allowing the threaded insert to expand slightly and lock into the part.
5. Disconnect the threaded insert from the shank foot that returns through the hole.
In all cases, please follow the safety instructions for drilling and thread cutting. And be sure to wear personal protective equipment (PPE) for your protection before starting work.