I showed a photo a few posts back of the 100-year-old fret wire that I was to use on the “gut” guitar.  The wire has no studs because it was produced by drawing it through a hole with the typical T-shaped profile.  I have seen the tool that Manuel de la Chica used to do this and it was called a “trefilador”.  A literal translation of that word would be trifiler (as in three-way profiler) The traditional way to get the wire to wedge into the fret slots is to strike the tang with a half-round file to produce irregularities on it.  In the video you can see the process which I decided to use.  The irregularities are very irregular and next time I will either use modern fret wire or a modern tool (which I have) that crimps the wire to get the wedging effect.  The frets were noticeably deformed by this process and hammering them in straight became a bit of a challenge.  Below you can see the photo of what was left after I finished fretting, there wasn’t much extra wire.  Sorry about the blurry video, no focus on the video camera.