The first project by Jay Barber and Edward Osgerby for Vitra, Tip Ton is a chair that lets you rock forward and back while you work. British industrial designers  Barber Osgerby run a successful studio from London and have gained international recognition on the back of projects including the olympic torch for the 2012 Summer Olympics in London and their Tobi Ishi table for B&B Italia. Here, Edward and Jay discuss the ideas behind Tip Ton and its relationship to their manufacturing approach to the torch.