Drilling Jig for RoboSub Competition Buoys
One of my coworkers was in a pinch--he was building 12 buoys as game pieces for the RoboSub competition field and needed about 40 of these 3 inch plastic "cookies" drilled very precisely and quickly. I made a quick drill jig for the drill press that aligns the cookies and guides the drill bit.
This project was another classic "whiteboard design, CAD, build". I considered a simple circular hole indexing jig like shown in this video, but chose to use a simpler template design so that multiple cookies could be drilled at once. I modeled the jig including the cookies as a SolidWorks assembly, and used assembly cuts to make holes for the alignment rods and bolt holes. I made detailed SolidWorks drawings with coordinates of the hole locations so that I could precisely locate them on the digital readouts of the lab's manual 3-axis mill.
This project was a great opportunity to learn about interference and clearance fits from the lab's machinists. I had 3 different fits to consider: the screws for clamping the cookies between the plates, the alignment rods, and the drilling holes. SolidWorks was helpful for determining screw clearances. A helpful machinist directed me to the tolerance charts for a proper interference fit.
This project was another classic "whiteboard design, CAD, build". I considered a simple circular hole indexing jig like shown in this video, but chose to use a simpler template design so that multiple cookies could be drilled at once. I modeled the jig including the cookies as a SolidWorks assembly, and used assembly cuts to make holes for the alignment rods and bolt holes. I made detailed SolidWorks drawings with coordinates of the hole locations so that I could precisely locate them on the digital readouts of the lab's manual 3-axis mill.
This project was a great opportunity to learn about interference and clearance fits from the lab's machinists. I had 3 different fits to consider: the screws for clamping the cookies between the plates, the alignment rods, and the drilling holes. SolidWorks was helpful for determining screw clearances. A helpful machinist directed me to the tolerance charts for a proper interference fit.