Each of the wheels pull one string about 15cm when moving from 0 to 180 degrees. If more torque is needed the nails pulling the strings can be moved closer to disk center. If more movement is needed they can be moved a bit more outwards. Each string is then guided trough a small hole in the white Teflon supporting blocks. I use Teflon simply because I have a lot of.
Tried to make it service friendly.
It is not.