I received an inquiry about being able to add a filter opening to my two-layer cotton masks. As these masks are already in the possession of many folks, I sought a simple solution.
I have experimented on my personal masks and there is a relatively simple option for folks who might want to “hack” their masks.
With my inner side facing me, I flipped the nose flap out of the way. Then I pinched the two layers of fabric and separated them so I can work with the inner layer.
I then used sharp scissors to snip a slit near the top just below the seam line. When wearing the mask, the slit sits just about at the nose tip. However, I also experimented with making the slit about an inch below the nose flap. I do not recommend a lower slit; it flapped open as it ran along the gap between lip and nose. (I’m glad I tested that one on an early Beta test mask of mine.)
I made the slit quite wide for a filter that may be more stiff. It ends about a thumb-width away from where nose flap pinched, or a little more than an inch from the side. It could be made less wide if you are comfortable manipulating your filter inside.
I do not have an overlocker/server machine, as I’m sure most folks don’t, so I turned to Aleene as I often do.
I keep a mini pack of Aleene’s fabric glues as any mender should. Aleene’s glue products are generally found at any Craft store. These are from Michael’s some years ago. I applied Stop Fraying to the edges of the slits, with particular attention to the corners. However, any of the fabric binding/bonding glues should work to keep the edges from fraying.
The Stop Fray does not include drying instructions, but I’m going to guess 24 hours should suffice before I can wash it since it is not needing to hold stuff together. It was dry to the touch in less than an hour.
As for what size filter can be used, an adult mask can accommodate something just less than 9″ and just over 3″.