Face shields can be used to help protecting personnel against COVID-19 through airborne droplets [CDC 1]. The current shortage and crisis calls for easy-to-manufacture and to use products [CDC 2]. This is a safety enhancement of the Prusa RC3 face shield band, printable in two hours or less, even at 70% infill. It has a safety hook to prevent the transparent plastic sheet from sliding and it also protects the forehead using half of the same type of standard-size sheet. It uses less material, since it does not need the printing of a brow guard or fully covered top, since the top plastic sheet is playing that role.

 

[CDC 1] https://www.cdc.gov/coronavirus/2019-ncov/prepare/transmission.html

[CDC 2] https://www.cdc.gov/coronavirus/2019-ncov/hcp/ppe-strategy/face-masks.html

 

Features:

 

. Safety hook preventing the bottom transparent plastic sheet from sliding

. Fully covering the face and the forehead with secured plastic sheets

. Using US-standard three-hole punch size and regular size plastic sheets

. Washable and reusable, and sheets also easy to swap

. Spaced away from the face to accommodate glasses and goggles and prevent fogging

. Large tabs to accommodate many types of elastic straps

. Fast to print and using less material than shields with solid tops or guards — approx. bounding box in mm: 200x147x30

. Can also be 3d-printed in batches of two or three, placed next to each other

 

Materials:

 

. 3d Printed headband (in PLA or other similar materials), rough quality slicing is sufficient, 70% infill with several solid bottom and top layers and minimal support (about 1mm) for the overhang hook, only for its lowest part. The support can be stacked onto the central lower prong and not necessarily on the building plate.

. Elastic band, such as regular sewing buttonhole elastic (for pants), rubber band

. clear plastic letter sized sheets: one for the bottom, and a half, cut lenghtwise for the top, both three-hole punched.

 

Note: three sheets and two headbands can be used to make two face shields. It is also a good idea to have a few spare sheets, for a quick swap, before needing to thoroughly wash and disinfect everything.

 

Procedure:

 

. 3D print the headband and clean the small supports between the front prong and the overhang hook

. Affix the elastic band.

. Cut one transparent sheet in half lengthwise, and three-hole punch it. Also three-hole-punch another sheet. The placement of the holes does not need to be very precise with respect to the edge of the sheet, just roughly in the middle of the length. What matters is only the distance between the holes.

. Affix the bottom, full-sized transparent sheet: first slide it up in between the central lower prong and the overhang hook, then into the prong, and then, slightly pulling, make the side prongs pass through its other holes.

. Affix the top half, at an angle: first the central top-prong through the central hole, and then the two side prongs, one by one, by slightly pulling.

 

When correctly inserted, the edges of the sheets should be tightly against the front part of the headband.