Having came up with a potential idea of how the gauge would work I decided to make a scaled up working version made of MDF.
So far this gauge concept seems to be the one that I’ll use in the final iteration. The only problems I still have with it are; to find a drive belt for the gears (an elastic band gives a really delayed reaction between the gears), and then to shrink this system to a size appropriate for inside the audio recorder.
I’m hoping to have this area resolved well by the end of this project as it is an important interaction for my device. A smooth gauge system will make it feel and look much more professional.