Here is a prototype of the nozzle for my CIJ Printer Project. The nozzle is made of an ultrasonic transducer from an ultrasonic bath with a hole drilled through the screw in the middle. For the 3D printer nozzle I drilled a M6 thread into the screw head and the M10*1 or 1/8" thread for the push in fitting was already at the other end of the transducer. I also placed an O - ring at the bottom of the push in fitting thread to prevent ink from leaking through the thread of the screw to the piezo. At the moment I have no driver for the piezos but I'm currently researching how to build one. There will also be a strobe LED needed to see the seperation of ink dropplets from the ink stream, which runs at the same frequency as the piezo.
So, next up will be building a test stand for the nozzle with strobe LED, a driver for driving the piezo and writing a script for automating the cycle.