Sept 18, 2020: UPDATE - I shaved the top of the mask so it doesn't fit so high on your face. Can be worn with glasses (download version 4)

July 31, 2020: NEW DESIGN (less fog, better sound, filter/no filter option combined into one!) https://youtu.be/WK1oP-mYQ7k

Most of us are wearing face masks these days to stop the spread of COVID-19. Unless you are wearing an N95 respirator, the primary goal of your face mask is to keep you from spreading viral particles by sneezing, coughing, talking and even breathing! The masks also partially protect you from incoming viral particles.

Besides being somewhat uncomfortable, your mask covers half your face! So you smile with your eyes, greet with a nod, and try to speak clearly enough that others can understand your muffled speech.

But what happens when you meet up with a friend or stranger who needs to read your lips to understand you?

I have access to a 3D printer and had been printing and supplying the the Montana Mask during the peak PPE shortage in the United States. A friend approached me about making a transparent mask so that she could better communicate with people who are hearing-impaired. There are instructions for sewing cloth masks with transparent film around the mouth (including this one on Instructables) and one for 3D printing by A Mask for All. I was not entirely satisfied by either option, so I set out to design my own, using the Montana Mask as a base.

This design has a large window that allows full view of the mouth from someone standing in front. Just as with the Montana Mask, weather strips provide a seal around the face. Air flows through vents around the chin and cheeks (that can be covered with a filter), keeping the window from getting fogged up as the wearer speaks.

Transparent Masks help each of us
cover our face without hiding it,
be understood when we speak,
share our SMILE !!!

Supplies

3D Printer and filament (I used PLA)
Transparent Plastic (I used 7mil clear covers)
Surgical or cloth mask (optional)
Self-Adhesive Weather Strips (I used D-Profile, 5/16" wide and 1/4" thick)
Elastic Straps
Scissors
Hot Glue

Step 1: Print the Mask

Download the STL file and print with a 3D printer. With the front of the mask facing down, no supports are are needed for the mask.

Note: Version 3 has the original shape, as shown in the photos. Version 4 is trimmed down so that the nose component is lower (can be worn with glasses)

I printed with Bright White PLA on a MakerBot Replicator+ at 220 degrees using a padded base, 20% infill and 0.3mm resolution. If you are printing on a machine with a heated bed, you will not need a base.

Note: You can scale these designs down to fit different face sizes.

Step 2: Install the Window

Place the printed mask face down on a piece of transparent plastic and trace the shape with marking pen. Cut the transparent plastic to the same size as the mask.

Apply hot glue along the front brim of the mask and immediately attach the transparent plastic. I was using a low heat hot gun, so I applied the hot glue in sections, pressing the transparent plastic down as I went, so as to get a good seal.

Ensure you have a good seal all around. You do not want air entering through gaps in the window!

Step 3: Attach the Weather Seal

Apply the weather seal to the inside edge of the mask, using its own adhesive.

The Montana Mask YouTube channel has a great video showing how to do this!

Step 4: Fit the Mask to Your Face

To get the best seal, you can heat the nose bridge of the mask slightly with a hair dryer or warm water. Then, press it against your face. It will quickly cool for a personalized fit.

The Montana Mask YouTube channel has a quick demonstration of fitting the mask with warm water:

Step 5: Finish Up With Elastic Strips

Feed soft elastic bands through the holes in the mask, one band passing through the top and bottom holes on the right side of the mask and one band passing through the holes on the left side. Choose a length so that when attached to your face, the elastic straps fit comfortably behind your ears while holding the mask snug against your face.

I prefer to include a little extra length in the elastic bands and use an ear saver (like this one) to secure the mask.

Step 6: Attach Your Filter (Optional)

Shorten the straps of a surgical mask a bit by tying a knot in each side. Secure each end to the knob at the top of the 3D-printed mask and wrap the surgical mask around the openings of the 3-D printed mask. Change the mask each time you use it!

If you do not have access to a surgical mask, choose a mask made of a material that is at least as breathable as the surgical mask. This Smart Air Filters page has a very thorough assessment of common household materials.

Step 7: Keep Your Mask Clean!

Masks will trap viral particles

Do not touch the mask while you are wearing it.
Wash your hands after handling a used mask.
Place the mask in a dry, sunny location between uses.
Clean your mask often with alcohol or with soap and water.

Snap a photo wearing the mask and share it in the comments! (don't forget to smile)

DISCLAIMER: This is a work in progress. Visitors to this site are encouraged to make the mask as described, conduct their own testing and provide feedback. I assume no liability and make no representations, warranties, or guarantees regarding the safety, efficacy, or appropriate use of these masks in any particular situation.