During the time we ran Wheelsmith, we made millions of spokes. The threading dies used in the big industrial machines are exactly the same as Mr Morizumi employs. Duh. We tracked wear and usage.
As many as 50,000 threadings can be achieved on one set especially if you micro-adjust thread depth (a Morizumi exclusive feature), and flip the dies since one half gets more use as we often shorten spokes by less than a full thread length.
Always best to use oil when threading and brush out the dies after a few runs. Any oil will do and rag or brush is effective. Use stuff that’s sustainable and smells good.
The 12/13g threading die set is a direct replacement for stock 14/15g dies. Leave any shims in place.
14/15g threading die set
12/13g threading die set