Are you a knitting enthusiast trying to save money? Here's how you can build a relatively simple machine to reclaim wool from sweaters.
Design blog PSFK showcases how Kingston University student Imogen Hedges created her "un-knitting machine" based on pedalling power from bicycles. The un-knitter sits and pedals, which pulls wool from a sweater and runs the fibre through a steaming kettle to make it easier to handle before being collected on a spindle on the bicycle's wheel. If you have an extra bicycle wheel and gearing, you could make your own with a bit of woodwork.
With this device, knitters can buy cheap sweaters from second-hand stores and reclaim the wool. Seems like a good way to make a conceivably expensive hobby a bit more frugal.