Prototype vol. pedal

[WineRider]

How easy is it to make a volume pedal? 1 hour, then a couple of hours at least in working out the gearing for the two pulley's. I have just finished a 'prettier one and will post once the lacquer is dry.
The seat is so simple...even for me.
I still can't get pics on here so here's the url: http://www.winerider.com/prototypes