A hybrid microspherical styli gluing and assembling process on micro-EDM

This article describes a hybrid gluing and assembling approach on micro-electrodischarge machining (EDM) to fabricate microglass spherical stylus tips for microcoordinate measurement machines (CMM) probing heads. Combining wire electrodischarge grinding (WEDG) technology and position controlling function of EDM, a microglass ball could be glued onto the front-top of the microtool successfully. Photo images and adhesion strength measurements were carried out to evaluate the gluing quality of the glass ball-ended stylus tips. The experimental results show that deviation of the largest profile of micro-stylus tips with a 0.07mm diameter could be as small as 1.53 μm, and the adhesion strength is approximately 12 mN without any detachment or bending. With further improvements of epoxy glue materials, this assembling process on micro-EDM will be a new approach to fabricate microspherical stylus tips for micro-CMMs probing heads.