from Union Bridge Labs:

Part machine. Part monster.  The yarn monster eats raw yarn and excretes perfectly rolled yarn balls.  A wireless remote control allows for the adjustment of the speed at which the monster consumes your yarn.  Yarn Monster eats other yarn winders for breakfast.

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The yarn winder is powered by a stepper motor, which is driven by an Easy Driver & Arduino Pro Mini.  The Arduino receives speed instructions via XBee from a remotely connected potentiometer.

The remote & controller boards were both designed in Eagle and etched using muriatic acid and H2O2.  Click here to view an image gallery that shows the etching process.