Apologies if this is old hat, but I use a couple of lovely Carmex miniature tool holders for internal screw threading. Fantastic things but rather expensive. I came to change the tip on one and found the M2 Torx screw to be stuck and immune to all my normal tricks to get it out. As the methods used got more and more desperate, the tiny T6 Torx socket got more and more mangled.
I resorted to a method I have used in the past with jammed stuff (including the odd tap) at much larger scales and was successful, saving the tool holder.
I took a nut and ran a countersink into the thread from one side, then I sat it on the head of the torx screw, and with the mig welder set to minimum, welded it on to the countersunk head of the screw. The M2 screw then came out easily with the aid of a spanner. The thing I was pleased about (apart from saving a chunk of money) was carrying this off at this small scale. A replacement screw came from Protool the next day…fantastic service!

