Summary Evezor is a SCARA class robot and today we etched the letter U into glass See a video of the making of here Our tool post, once again, was just a hunk of 2X4. Then we used a hose clamp to secure the rotary tool to the tool post. We used a diamond bit to do the glass etching and some lightly soapy water as coolant. Find out more about our arm at See our other projects we've made with our arm Hot Wire Foam Cutting