MaskTech: Sewing "swim lanes" for the ribs first

Mid 2021 update:  High thread count cotton and/or multi-layer polyester satin isn't a good choice for high filtration masks. They're not breathable enough at mid filtration performance. And additional layering to get to hight filtration still only decreases breathability further. With that they get hot and uncomfortable as well as giving your chest muscles a good workout.

Just practicing here, this mask is for the trash rather than for donation

Zipties (cut up here as the ones I had were too long)

Sticking out a little, for the sake of the photo:

Folded again, ready to sew:

Pushed home, then sewn:

Excess cut off:

Bias tape sewn, mask no longer inside out:

Holding it to my face, it feels solid. The ribs are 

holding everything into position quite nicely.