Peoplefrom with everything from surgical masks to to bandanas, but keeping those coverings securely over your mouth and nose isn't always easy. Surgical masks loop around your ears and can be uncomfortable. Cloth masks with ties take longer to put on and need to be tied tightly. Bandanas cover a large area, but not closely, and can slip off easily.
Having previously, I still hadn't found exactly what I was looking for. Using mostly cloth masks (yes, made by my mother) and more recently a black bandanna worthy of a stagecoach robbery, I wanted something that would make it easy to put on and take off my face covering, while also holding it in place securely.
So I fired up a 3D design program, in this case the easy-to-use (and free) browser-based Tinkercad, and started designing my own set of mask clips. One of my favorite 3D printing tricks is to combine 3D-printed parts with magnets to create more useful designs, so I sketched out a set of mask clips that don't require you to tie anything or latch plastic clips together. Instead, my clips use small magnets to fit together securely.
The version here is the result of some trial and error: As I printed and tested different designs I made the hole for the magnet deeper, so it fits flush with the plastic, and enlarged the strap holders for easier adjustments. There's just one STL file (the file format for 3D printing software) -- print two copies of it and they should fit together perfectly.
In this case I used magnets with a diameter of 8mm and a depth of 3mm. I got them at a hardware store, but they're easy to find online as well. If you want to use different-size magnets, you can tweak the design in my Tinkercad file, located here. Depending on your filament and printer, the magnet should fit snugly in the clip, but I used some super glue to permanently attach it.
You can download the STL file for my magnetic mask clip here from Thingiverse, or dowload the original Tinkercad file here.