A 3D printed face mask with a 100% Silicone seal. The per unit cost is about $3 including screws. This is a one size fits all approach but can be scaled (uniformly, on all parts) up or down for different sized users. The silicone seal is thin and flexible. It's a good fit and comfort level on average.
Producing the mold can be done with silicone mold making material or 100% silicone caulk (some caulks may cause skin irritation). Smooth On Ecoflex 00-30 has been recommended by one individual in the medical community. The example uses caulk. For the exact process, watch this video https://youtu.be/gwOZ_gwkojg
The filter window is relatively large for easier breathing through dense materials however it is an irregular shape.
To build 1 device you will need; 1 Mask, 1 Filter Cap, 1 Mold (reusable), 1 set of 4 Strap Locks (if using 1/2" elastic band).
!!!This device has not been professionally tested to assess any aspect of the design or functionality. It has not been approved by any regulatory body and should serve as backup PPE only in the even that standard PPE is not available.
SHOPPING LIST:
Dritz Braided Elastic Band 1/2" - Black (appears to be sold out in most places)
100% Silicone Kitchen and Bath Caulk (Any brand. Food Safe is Good, or Aquarium Grade is Best)
Petroleum Jelly "Mold Release" (Any brand)
Screws and Nuts (4x) - Imperial: 8/32 x 5/8 Metric M3 x 16
Printer Plastic (Whatever is recommended by the medical community. I used PETG for the prototype)
