We present an innovative drawing tool that can detect tangible drawing instruments on a capacitive multi-touch tablet. There are three core components to the system: the tangible hardware, the recognizer used to identify the tangibles, and the drawing application. Our tangible drawing instruments include a ruler, protractor and set square. Users can apply these familiar physical instruments to construct digital ink drawings on a tablet in an intuitive and engaging manner. The user evaluation shows that the tangible drawing tools are easy to use and have a high rate of recognition on the touch screen.