15-03-2021, 04:05 PM
If you don't have a thread file, a knife-shaped needle file will do.
Usually the biggest difficulty is that the end of the shaft has spread, so any file will do to bring the outside diameter back to where is should be.
Then judicious use of a fine file to make the thread look something like it should do.
Once the nut is past the "restored" bit, it is on reasonably good threads, and when tightened the rough bit is poking out past the end of the nut - so it hasn't got to be anything like perfect.
Usually the biggest difficulty is that the end of the shaft has spread, so any file will do to bring the outside diameter back to where is should be.
Then judicious use of a fine file to make the thread look something like it should do.
Once the nut is past the "restored" bit, it is on reasonably good threads, and when tightened the rough bit is poking out past the end of the nut - so it hasn't got to be anything like perfect.