USA 3-hole | 15mm | RC3 | ear flare | face shield

prusaprinters

<p><strong>A remix of Prusa's RC3 face shield with:</strong></p> <ul> <li>USA 4.25" 3-hole punch spacing (1/4" or 6mm holes)</li> <li>15mm z-height (quicker print with minimal impact on durability)</li> <li>improved comfort near ears via 7.5° flare</li> <li>filets instead of chamfers to reduce fabric snags</li> <li>simplified rubber band hold</li> <li>no logos</li> </ul> <p><strong>v2.1 update:</strong></p> <ul> <li>Mounting posts updated<ul> <li>post spacing corrected</li> <li>optimized for pre-punched overhead projector sheets OR manual 3-hole punch with circular holes</li> <li>posts have ridges at the tip to prevent thin plastic from falling down</li> </ul> </li> <li>Comfort<ul> <li>165mm model added for better fitment on smaller heads</li> </ul> </li> </ul> <p><strong>v2.2 update:</strong></p> <ul> <li>rubber band holder updated to prevent band from falling off when face shield is not in use.</li> </ul> <p><strong>v2.3 update:</strong></p> <ul> <li>step file added</li> <li>mounting posts widened by 0.5mm to improve fitment for larger sheet holes</li> </ul> <h3>Print instructions</h3><p><strong>For Mk2.5 and later (Mk2 OK too, but slice your own gcode!)</strong></p> <p>Standard PETG 0.4mm nozzle profile is OK but here are some optimizations for print speed without bumping extruder beyond 240 degrees and ruining quality:</p> <ul> <li><strong>layers &amp; perimeters</strong><ul> <li>0.25 layer height</li> <li>3 bottom and 3 top layers</li> </ul> </li> <li><strong>speeds</strong><ul> <li>70-90 mm/s inner perimeter speed</li> <li>60-80mm/s outer perimeter speed (depending on printer tuning, there may be surface ghosting which won't affect durability or comfort)</li> <li>60-70mm/s gap fill (most "gaps" are long stretches between perimeters so this won't vibrate the printer unlike other models)</li> <li>100-200mm/s infill</li> </ul> </li> <li><strong>infill</strong><ul> <li>15%</li> <li>gyroid interior, rectilinear top/bottom</li> </ul> </li> <li><strong>advanced</strong><ul> <li>0.5mm first layer extrusion width (improved bed adhesion)</li> <li>0.6mm infill (speed)</li> <li>0.5mm solid infill (speed)</li> </ul> </li> </ul>