PaperMake: DIY Half-Face Mask for Everyone

Design Motivation

On 25th March 2020, the Covid-19 pandemic had already struck the world hard. With severe shortages of surgical masks around the world, with people turn to interesting innovations in a bid to minimize exposure to the virus particles which are naked to our eyes. The most promising designs were 100% layered cotton fabric which were sewn with/without slit as well as an optional nose bridge. With amazing people pooling together resources to sew and cut pieces of fabric together, that brings me to ponder about those who fall through the cracks and do not have access to such fabrics, sewing machines, 3D printers or lasercutters.

As a design engineer, maker and papercraft enthusiast, I decided to explore and challenge myself on the possibilities to design a functional mask that could be printed in an A4 sheet of paper, cut and folded into a reasonably functioning mask which could potentially provide users with some sort of protection or containment from large particles. This design would hopefully give an alternative avenue for individuals to find protection for themselves as not everyone have the same resources.

Functional Requirements/Constraints

In a sheet form, flat-packed and able to be mass produced via stamping/laser-cutting/cutting
Usage of household objects which are readily available and cheap
Modular in nature (filter per user availability; sheet material to form mask can be plastic)
Minimize large particles expelled by wearer when you are ill, from reaching the environment (Good seal)
Used as physical barrier to protect user from large droplets
Large enough area for breath-ability and added resistance against coughing

WARNING:

This design is NOT validated by healthcare professionals for use.
Wearing an unvalidated mask may increase your risk of a contracting the virus by giving you a false sense of security.
Wearing a validated mask, practice social distancing and proper hygiene like washing your hands with soap and not touching your faces are the preferred protection methods so far.

Supplies

1 X A4 Sized ~0.3mm Cardstock/Plastic Sheet/Corrugated Cardboard (Template Printed; Non-porous)
4 X Rubber Bands
1 X Scissors/Pen-Knife
1 X Masking Tape/Double-Sided Tape (or non-porous tape)
1 X Sharp Tip Tool (e.g. Math Compass/Needle etc.)
1 X 10cm by 8cm Filter Sheet (size depends on your air inlet/outlet)

Step 1: Download & Print the Template

Download the template from the attachment. The .pdf document is set to A4 size. Make sure you have set the printer settings to the paper that you are using. Then set actual size and print in landscape. You may select the pages to print the necessary pages. Designs are on page 3 & 4.

Due to time constraints, the drafted document is mainly fitting the 99th percentile of the an average human's face (i.e. it's huge in some sense). An average chin to head height length of about 10 inches. If anyone's interested, I can scale to create different sizes but feel free to scale the design to suit your needs. Tell me if it works. Do note that scaling directly will impact the hole sizes as well.

PaperMake_Template_V7.2.pdf
Download

Step 2: Cut Out the Template

Most of the assembly instructions are in the video of this Instructable and in the .pdf document as well. You may refer to it for further instructions on how to make the cut-outs. If you have followed the instructions properly, you will end up with a similar layout as per image. An average manual cutting time takes about 5-8 minutes.

*Note:

If you have a lasercutter or cricut machine, you may make the cutouts respectively.
The ones shown in the image was cut by a lasercutter so that it's more presentable.
The design can also be stamped by a die for mass production (2D designs are beautiful isn't it!)

Step 3: Make Mountain Folds and Valley Fold

Create mountain folds on the dotted lines and valley folds on the dashed lines.

Pro-Tips:

Feel free to score these lines with a penknife and ruler prior to bending to make the folds easier.
To allow seamless assembly make sure that the width of the slits that were cut are cut to length and remove any burrs/fraying on the cardstock from penknife cutting.
For the nose bridge area, fold the sides of the mask inwards while pushing down on the top of the flats (see photo for illustration)

Step 4: Insert the Flaps Into the Slits

Pro-Tip:

To hold the mask in place, insert the flaps into the slips and fold the flaps backwards (see images)

Step 5: Cut, Paste and Seal the Edges

Using non-porous tape and a pair of scissors, cut pieces of tape to size and seal off all the 4 interfacing edges to create a seemless barrier to the mask.

Pro-Tip:

Use a wide enough tape to ease for application
Cut half of the width on the ends to seal of intersecting faces (see 2nd image)
Press down firmly on the edges to ensure good seal

Step 6: Attaching the Filter

Find a piece of usable filter material (e.g. 100% Cotton Layered Cloth etc.) and slice it up into a approximately 10cm by 8cm (or cut to whatever shape you have deemed suitable for your size)
Cut a strip of double-sided tape and place it at one end of the filter and remove the liner
Place the filter into position at the mask
Tape up the rest of the edges of the filter onto the mask
Press down on the edges and use a wider width tape to ensure better sealing.

For further information on the types of materials to use:

Beware of the material that you are using. Some filters contain glass fibers which may cause damage to the lungs if inhaled. Also, some materials deteriorate with washing. Thus, their lifespan might not be long as well. Research your materials well before using!

Pro-Tip:

If you want your mask design to be resistant to pressure built up (e.g. coughing), make sure your path of least resistance for air flow is through the filter and not through the sides or the top of your mask
To do this, you can increase the area of ventilation, tighten your mask (i.e. increase resistance on other edges relative to the ventilation areas) or choose a filter combination that is breathable but still be able to protect against virus particles.
Particle Filtration Efficiency (PFE) is the metric to evaluate a good filter.

Please comment down below on any proven filter combinations for me to add to this list.

Step 7: Cut 4 Elastic Bands Into Strips

Use a pair a scissors and cut the elastic bands.

Pro-Tip:

Choosing an elastic band that has high stiffness will vary how tight your mask is
The ones use in the examples are your off the shelf elastic bands
You may use a band tensioner to increase force of your bands later

Step 8: Loop the Rubber Band Onto the Mask

Follow the images shown above.

Step 9: Tie Two Strips of Elastic Bands Together

To form a complete ear loop, tie two elastic bands together with a square knot.

How to tie a square-knot:

https://www.youtube.com/watch?v=FjQmT32qzWU&t=82s

Pro-Tip:

Vary the eventual length of the hook (inversely proportional to the stiffness of the elastic band)
Pull taut on both ends of the rubber to tighten the knot

Step 10: Complete!

And....you're done!

Seal Check:

Conduct a seal check by covering the air outlets with your hands.
Inhale deeply check for pressure being felt in the mask (refer to the end of video for example)
Exhale out deeply and feel for any air leak (refer to the end of video for example)

Please note once again that this mask provides some sort of protection if built well but is still not validated by any healthcare professionals. Use with caution.

Step 11: Bonus: Improving Seal+Comfort With Mask Straps

Sticking true to my design objectives and constraints, I have created a prove of concept mask strap that can be produced quickly using a pair of scissors. Currently, a 0.3mm cardstock is used in the design. Changing into plastic sheet will increase its durability and resistance against moisture. A template will be up soon if there's interest. Do comment down below me if anyone is keen.

Alright! That's all for now!

Stay safe and take care.