Using a thread file to repair bolt threads. If you have a bolt with damaged threads, you could buy a new bolt, use a die to recut the threads, use a thread chaser, or repair them with a thread restoring file. A thread file does the same thing as a thread chaser but the file is cheaper and can repair threads on a much wider variety of bolts since diameter is not a factor. See the links below for the parts and tools I used:

SAE Thread Repair File (11-24 TPI):
https://amzn.to/37fKnP5 (affiliate*)

SAE Thread Repair File (9-32 TPI):
https://amzn.to/3lRySl6 (affiliate*)

Metric Thread Repair File (0.75-3.0 TPM):
https://amzn.to/2T16P6j (affiliate*)

SAE & Metric Thread Restorer File Set:
https://amzn.to/2T1hspN (affiliate*)

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