Who would have thought that fretlets would become a “theme” so fast. While still crazy busy installing the fret scanning system in my new guitar (see previous post), I got approached by local guitar player Julia Reidy about the possibility of modding a guitar for unusual tunings, e.g. just intonation or Asian tuning systems like slendro.

This is not a new idea of course – there’s many examples of such guitars and one can even buy necks with certain tunings. The challenge though was to build this in a way that would allow for experimentation, i.e. with flexible fret positions.

After some research we came across the Youtube channel of Tolgahan Çoğulu and decided to try something similar. The way he approached the problem was to cut long channels into the fretboard and then put fretlets on small pieces of wood that can slide inside these channels.

Our first experiments were done on an old beater guitar of Julia’s. I decided to use little pieces of brass instead of wood to put the fretlets on:

The trick is to get the size of the channel just right, so the friction keeps the brass piece in, but allows for it to be moved around.

Here’s the neck with 10 pieces:

After this proof of concept, we moved on to the actual guitar. I had an old fretless guitar that I had stopped playing decades ago, so it was the perfect instrument to bring back to life for this.

Of course, cutting the channels with the required precision (<0.1mm) was another job for the CNC. Sadly the longest cut I can make with my current machine is 400mm, so I couldn’t do the whole length of the neck in one pass…

…but with some extra effort I eventually got it done:

And here’s a picture by Julia with the majority of the fretlets installed:

Looking forward to the music!