How to make the ultimate DIY coronavirus mask

[dreamshark]

This is for you, bibliophile ! For people who are not interested in making masks, the tldr version is: mixed materials are best. Good combinations are a layer of cotton plus a layer of silk or chiffon or polypropylene. For even greater effectiveness, include a pocket for a removable filter of some kind of non-woven material. Fit, breathability, and adjustability are also important. And yes, if you follow these guidelines you will end up with a mask that protects the wearer as well as other people.

Here's my favorite Gen 2 mask. The outer layer is a densely woven cotton. Inner layer is an unusually soft piece of chiffon, which both provides electrostatic filtering and is outstandingly breathable. There's a filter pocket currently holding a piece of soft felt. The design is super adjustable, which allows me to get a close fit at the sides and top. The side channels not only allow any kind of fastener to be used, they can be scrunched down as needed to get the perfect fit at the sides. And there's a pipe cleaner in the top edge for fitting around the nose.

More detailed info and links below the pictures. If you would like me to make you a mask, let me know.

The point of using mixed materials is to get different types of filtering. Tightly woven cotton is good at mechanical filtering (for larger droplets). But if you add a layer of a "negatively charged material" you get electrostatic filtering that stops smaller particles. And a non-woven filter material (such as felt, polypropylene, interfacing) provides even more mechanical filtering without affecting breathability very much. That's important because if you overdo the dense cotton and make the mask too hard to breathe through you just end up drawing air in around the sides and sabotaging the whole filtering thing. That's also why all the adjustability features are important: you need a good fit.

Here's a link to an article from a couple of months ago by a textile scientist. Note that she did not do any filtering experiments, just analyzed existing medical masks and applied her specialized knowledge of fabrics to make some suggestions. I also note that although she may know a lot about the chemical composition of fabrics, she doesn't appear to know much about sewing. She seems to think that you would have to throw away mask components made from interfacing after each use, which makes no sense. Interfacing is meant to be sewn into clothing to stiffen it, and is (of course) perfectly washable. It's too stiff to MAKE a mask from, but would make a perfectly fine permanent filter layer.  She has some interesting suggestions for materials that I hadn't thought of or seen elsewhere.

And here's a link to the recently released ACS study that recommends mixed fabrics. These guys did actual studies, but the kind where you blow stuff through a swatch of fabric rather than sewing it into masks. I assume that's why they make no suggestions about the specific order of the materials (inner/outer layers) and don't even get into the "protects the wearer" vs "protects others" controversy. I was impressed by how closely the results matched the textile scientist's hypothetical analysis. I guess there really is such a thing as "negatively charged fabric." Huh.

Here's a link to my mask gallery. My favorite masks are at the top. Construction notes are in the (i) Info field. Here's some of the combinations of materials that I've used since I started Gen 2.

• Ultimate Music Mask (featured above): quilters cotton/chiffon with felt filter
• Japan Scarf Mask: Heavy silk scarf for outer layer+ white cotton inner layer. My default non-intrusive filter is a piece of polypropylene from reusable shopping bag. 
• Forest Silk Mask: 3 layers of delicate silk + forest green poly/cotton blend. Polypropylene filter
• B/W Music Mask: Woven cotton outer layer+ medium heavy black silk inner. No filter at the moment for coolth
• I've retrofitted some of my older all-cotton masks with electrostatic filters: either a couple of layers of polypropylene or (my latest brainstorm) crumpled pieces of light silk from torn up old scarves. Adds electrostatic filtering with practically no weight and makes the mask soft and puffy. And my refusal to throw away those tattered old silk scarves is finally vindicated! 

 

 

Comments

[spiderplanet]

Looks great! What are you using for the "ties" (for lack of a better term)?

[dreamshark]

My two favorite types of fastener are:

1) One continuous loop of some kind of elastic strung through the ear channels and tied (or otherwise fastened together). You need about 30". The mask shown in this entry uses something called Stretch Magic Silkie necklaces that can be daisy chained together. The only problem with them is that there is no easy way to change the length. Two of the long ones just happen to work perfectly for Richard, who has a giant head. Two short and one long works for me. If you don't happen to have these weird devices lying around, a piece of round elastic cord works great. A long piece of flat elastic also works, although it tends to get twisted.

2) One long bootlace (or two shoelaces tied together) strung through the side channels and over the top. 48" is the ideal length. You position the top portion on your head, pull it down through the side channels to tighten, and tie it at the nape of the neck. A variation that makes this method even better is to sew a 6" piece of flat elastic in the middle. It looks a little sloppy, but gives the absolutely best and most configurable fit.

OTHER OPTIONS
* If you insist, you can string short pieces of elastic through the side channels and loop them around your ears. Apparently this works for some people. It doesn't work well for me, and rarely works at all for men with larger heads. It is the most popular form of fastener for cloth masks, mostly because people don't realize there are better options.

* I also have some older masks where I sewed cloth ties into the corners. You can use shoe laces, lengths of bias tape, repurposed drawstrings, or even lengths of t-shirt material pulled tight so they roll up. This works fine, but the side channels give a better fit so I don't use that design any more.

[spiderplanet]

The best mask I made uses short pieces of T-shirt yarn, with a rubber band tied in between. I made bias tape at first, it's unpleasant with long hair and it tends to get tangled up.

I like it well enough that I would do that method if I were making more. I bought some better made masks from better sewers than me, so I'm all set now.

[dreamshark]

It is very hard to make a mask that just works for anybody, especially deciding on a strategy for securing the mask.

For me the One Long Bootlace method works the best. It took a little practice putting it on at first, but it's by far the most adjustable. But anything that has to be tied is a problem for people with arthritis or small children, which is why I finally gave in and bought a whole reel of round elastic cord, which opens up more possibilities.

I hadn't thought about long hair. I can see how that complicates the whole tying at the nape of neck thing. I would think that the continuous loop of round elastic would still work with long hair. I put the bottom part of the loop at the nape, but I think it also works to put both parts of the loop over the hair, right? Like with those eye masks people use on airplanes?

What kind of ties are on the masks you bought, and how does that work for you?

[spiderplanet]

The ones that I bought are a single long loop of elastic. Elastic doesn't get caught in hair as easily as rubber does, so it's good. Having the least little bit of rubber band that is necessary is probably my preferred method because I know it's the least likely to catch in my hair. I wear a hat at work, it's nice that the only rubber part goes on top of my hat.

[dreamshark]

By "elastic" do you mean that flat white elastic strip, usually about 1/4" wide? What do you mean by "rubber"? Are you talking about an actual rubber band? Or round elastic cord like this stuff I just bought and am currently enamored of:

https://www.amazon.com/gp/product/B00PUPYL50/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

"Rubber" could also describe my Stretch Magic Silkies, but nobody but me has ever heard of those. They are rubbery but very smooth. Not sure if they would catch in long hair or not. They don't catch in my hair.

[spiderplanet]

Yes, "elastic" is 1/4" elastic cord, "rubber" is uncoated rubber bands. The round stuff looks pretty good. I bet that works great.

[spiderplanet]

I have a bracelet that exploded. What is the approximate diameter of a "stretch magic silkie"? That looks like it might work.

[dreamshark]

Stretch Magic Silkie necklaces are 2mm. Here's what the package looks like.

https://www.joann.com/pepperell-braiding-stretch-magic-silkies-necklace-cords-black-and-white/1438225.html?utm_source=google&utm_medium=cpc&gclid=Cj0KCQjw9IX4BRCcARIsAOD2OB2RARkdUzoW5dpRYPwGsyYdvoBCqS4_uUKRHgX8bom2WtwkGRqr_rcaAo_bEALw_wcB

[spiderplanet]

This is much closer to 1mm. I should accept that I'm going to use embroidery floss and accept reality.

[arkuat]

I am so glad you have kept up with this and gotten further into it!

[dreamshark]

Thanks for the encouragement! I hope your elephant mask is working for you. That one was kind of a nice combination of materials (especially for hot weather) but would have been even more effective with a filter pocket. I think it's a pretty mask and the colors are good for you, but have never seen it on. If you feel like taking a selfie wearing the mask I wouldn't mind seeing it.