The ABC Face Shield

grabcad

Atlanta Beats Covid (ABC) has been working closely with Atlanta Shield Makers to develop a face shield designed specifically for healthcare workers. Our unique approach focuses on 3D printing a master mold, then using that mold to cast plastic parts. This innovative design meets the following requirements: Beginner-friendly for new plastic casters, adaptable to various three-hole-punched visor materials, optimized for minimal silicone usage, easy to demold, and scalable for large production quantities. To achieve these goals, we've created a remixed Prusa (US) that incorporates a browshield and several small geometry changes to make it molding-friendly. The Solidworks part file _0_ contains the geometry for each subsequent part, providing the best results when remixing. This is where you should start. It's also possible to 3D print the ABC face shield frame directly by downloading and slicing file _1_. We've had excellent results with a coarse 0.35mm layer-height PLA print taking around 2 hours. For molding and casting, we provide two STL files ready for use: File _2_ contains the frame geometry from _1_ but with an additional flat plinth that provides a crisp edge when molding. To achieve the best results, print this file in a high-resolution printer such as SLA or Polyjet, or post-process it. We've had great success with SLA, Polyjet, and acetone-smoothed ABS. File _3_ is simply a mold box that provides a 0.5" border around the outside of the part to contain the silicone rubber. It fits snugly around the plinth, secured with hot glue or tape to create the final master pattern ready for pouring. We use Smooth-On MoldStar 16 for this (around 22floz per mold), but many other silicone rubber options exist. The last part to be made is the strap clip, which hooks over the rear-most pegs on the frame and incorporates a tension adjustment. File _4a_ provides the DXF of this part for laser cutting, where we use 0.100" acrylic with good success. File _4b_ is the 3D version of this part in case you prefer to 3D print it. For the visor material, we've proven our frame with several options: overhead transparency acetate with three-hole-punched holes, binder covers with three-hole-punched holes, and 34mil PET sheet CNCed or laser cut according to the original Prusa geometry found here: https://www.prusaprinters.org/prints/27950-prusa-face-shield-us-version We finish the assembly with the following components: 12mm self-adhesive foam cut into 9"x0.75" strips, available at https://tntcosplaysupply.com/product/eva-foam-sheets/, and 0.5" knitted elastic found at https://tntcosplaysupply.com/product/eva-foam-sheets/. Note that this design or variants similar to it are free to use. Please share it far and wide, and we'd love to hear your feedback or remixes.