Making a Custom Die on the Proxxon PD 250/e Lathe

Making a die is the natural counterpart to making a tap, and is the reason I made my shop made tap in the first place. The custom slideway threads on my G Boley watchmakers lathe are an unusual geometry, but are damaged, and I need to chase them with a die to clean up the form. I researched the techniques involved from books and YouTube videos, and took the shop made tap out for its first real work. The thread in question is a left hand 4mm by pitch with a 55 degree angle. It predates most modern thr