A simple and quite effective Bubble machine, or whatever you call it in English.... It is a Seifenblasenmaschine, you have to love german... As a Fan i use a 120mm radial Fan, you need quite some power The Motor for the Wheel is a N20 with 100 rpm, since i can controll both Motors with a simple pwm motor controller you can twist it best for your bubble solution. For Power i use a small 12V LED driver.