Can anyone recommend the correct tool to touch up the damaged tang thread on a TR period army dagger? Also, if available where it might be obtained. Thanks.

You need to go to a machine shop with the blade. They will measure the thread with a thread gauge s and run a die over the thread. In most cases however the pommel is damaged rather than the tang. These can be fixed with the correct Heli-coil.
As an aside 75% of those buggered SA scabbard screws were messed up cause most guys do not run the right tap through the holes BEFORE putting in the screw. If you get the proper tap and take the time to do this you can achieve a beauty set.
Oh, the other 24.99%?
They are buggered cause people do not use the correct screw driver!!

A peek at taps and dies

Or, take the blade to the hardware store. Look in the metric nut section and find a nut that screws on to the threaded tang nicely and tightly. Note the box from whence it cometh. Buy or borrow a die of that size and run it down the tang.

Paul, and Dave - thanks to both for your advice.

Regards
Barry

Barry pass it to me at the next show and I will do it for you
Paul

Thanks, Paul

Hi Barry,
If it's any help I have the correct tap and die set and a helicoil kit to do the pommel.
Best wishes,
Ian