I've updated Basschat with up to the above stages. The next couple of weeks are going to be a bit bitty - I need Alex here to fine-tune the neck profile and his and my calendars are like ships passing in the night!
In the meantime, someone on Basschat was interested how the Steinbergers work - below is what I posted if it is of any interest :
You wind the knob at the back until the spindle rises to the top, exposing the string hole at its base:
You thread the string through the hole and pull tight while clamping it by rotating the 'T' bar at the top (the T is a simple screwed clamp):
You then rotate the knob at the back in the opposite direction, which pulls the spindle down into the housing and takes the string with it, tightening it as it goes. This is the 4th string now at full pitch:
Clearly, the far end of the string can be clipped at the other side of the spindle but, while I am fitting am removing the strings regularly, it is easier to leave them long.
It is a very clever design and they are well made:
They are as smooth as silk. No backlash and very accurate and controllable tuning.
They can be placed anywhere, unlike conventional tuners that have to be close enough to the headstock side for the adjuster clearance. And so, the headstock can be any shape you like.
The string is always 'at the bottom of the peg', maximising break angle over the nut