COVID-19 low-cost disposable face shield

The COVID-19 crisis has seen the world coming up with novel solutions to personal protective equipment (PPE). In many countries the problem is less to do with a shortage of PPE and more to do with distribution challenges of getting the PPE to the users. For this reason local distributed manufacturing, through the use of 3D printers and/or laser cutters, is becoming a popular method for resolving such distribution challenges.

Face shields have been a popular example for which 3D printers have been proposed. This is completely fine if just making a few shields, but scaling up to larger production, particularly with desktop printers, can be hard. Some of the shortest print times we have seen, just for the shield frames, have been around 20 minutes. In contrast, laser cutting is a substantially faster method of manufacturing face shields.

Associate Professor Don Clucas, of the University of Canterbury, has developed a rapidly producible, disposable, low-cost face shield for medical staff. Most importantly, it is very similar to what medical staff are used to wearing, so is less likely to see any objection to it being used. It may also be of use for essential care facilities like aged care homes and people working with the disabled, family and friends looking after infected and quarantined patients. Also essential staff working in supermarkets may feel more comfortable if wearing one. Although the DHBs may have plenty, the wider community that could benefit from may not. Sometimes these things provide comfort to the wearer and makes them more comfortable to go to work.

Comprised of a laser cut 0.25mm clear PET "visor", a laser cut foam pad for spacing and ventilation and an elastic band, it can be manufactured in about 15 seconds of laser cutting for the visor and just over 15 seconds for the foam pad.

The DXF or AI files for laser cutting are available below:

Visor

visor DXF file

 

visor Adobe Illustrator file

 

dimensioned PDF of visor for manual cutting

Notes: Use 0.25mm thick PET as is commonly used by the packaging industry for vacuum forming. When laser cutting, it is best to raise the PET above the honeycomb to avoid soot marking the bottom of the visor.

WARNING: Great care should be taken when laser cutting , and laser cutters should not be left running unobserved.

After cutting, use 50/50 dish washing liquid and water to clean the shield. This both cleans and helps prevent static and fogging.

Foam block

foam DXF file

 

foam Adobe Illustrator file

 

dimensioned PDF of foam for manual cutting

Notes: the foam is 30mm~35mm thick open cell foam like that used in foam mattresses.

WARNING: Some foams are extremely flammable! Great care should be taken when laser cutting foam, and the laser cutter should not be left running unobserved.

When laser cutting, it is best to raise the PET above the honeycomb to avoid soot marking the bottom of the foam.

If necessary, wash the visor using a 50/50 dishwashing liquid and water mix, and dry it before use. This process can reduce fogging.

Washing of the foam can also be done with another detergent, even use a washing machine and dryer. However, it must be thoroughly dry before sticking.

If you come up with any further improvements, please email them to us at olaf.diegel@auckland.ac.nz and we'll update the downloadable files on the site.

The model wearing the face shield is Emma Clucas, who also put together the first production run of face shields.

ASSEMBLY INSTRUCTIONS

First laser cut the PET visor and foam block with the files provided. If no laser cutter is available, they can also be cut by hand. Then follow the simple assembly instructions below. If you are making many units, we suggest you make a jig to make assembly faster and more precise.

copyright 2020, olaf diegel