--- In makingthings@yahoogroups.com, "gpak99" <gpakbulk@...> wrote:
>
> hello list,
> i'm working on a project that involves pulling a piano string that
it stretches back and forth
> to get tone differences.

have you considered the effect of all this tuning on the string
itself. seems like it would get harder and harder to tune then break.

perhaps a linear actuator to stop the string at different places along
its length. maybe a piece of guitar nut or bridge or for a brighter
tone a piece of glass or metal tube.

this might also be more visually interesting.

also how are you planning to set the string in motion? pick? hammer?
magnets?