Zap's Custom 3D Printed Facemask

[ZapWizard]

These days my EDC now includes a face mask.
I am not satisfied with the face masks currently on the market. They are either way too large and leak out the sides, or are simply uncomfortable and bulky.


Via the 3D printing nerd on YouTube: I came across the Bellus 3D App, which allows you make a surprisingly accurate 3D scan of your face using any iPhone that has Face ID.

Their app also can generate a 3D printable frame that makes existing masks fit better. And their frame solution works great to seal the edges and in general makes the mask a bit more comfortable. However it still pinched the top of my nose, and require extra straps. It also pulled down any mask material such that is smashed the tip of my nose.

As a mechanical product engineer I couldn't leave well enough alone and starting thinking of a better design. There are already a lot of very bulky designs out there, and the NIH is working to share [urlhttps://3dprint.nih.gov/ 3D printable personal protection gear[/url].

Here are my goals:

• Comfortable
• Easy to take on/off
• Seals to my face
• Swappable/washable filters
• Easy to clean components
• Doesn't smash my nose

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So after many hours of design and various alternate designs that didn't work for one reason or another, I have settled on this design. It uses a gasket, frame, filter holder, and cloth filter.

To design it I used the Bellus3D app to do a full head scan which  I could import into my CAD software (Solid Edge). I opened the scan in MeshMixer and then smoothed it out a bit. Solid Edge has some cool reverse engineering tools that let you work from tessellated models and 3D scans. This gives me some surfaces to work from that perfectly fit my face.

I then model in the silicone foam gasket that will seal against my face. The frame is then designed to half-grip the gasket. It specifically has gaps near the bridge of my nose to ensure that the harder plastic doesn't touch, only the gasket. The frame also has hooks for the strap, which I will use either bungee cord, or silicone o-ring stock as the material. (My prototype uses a thinner o-ring stock, and its actually quite stretchy and comfortable).

A series of magnets ring the inside and work to hold the filter onto the frame. A small gap between the two allows the fabric to wrap around and be held in place. The plan is to stitch the cloth layers together into easy to swap/wash patches.

N95 masks are made by actually spraying the fibers directly into molds. You can't buy the raw material on its own (no matter what Alibaba says).
To that end, I need to use a cloth mask. I did some research and can across an article that scientifically compared a bunch of various materials.
Their results showed that layers of 600 count cotton and chiffon was nearly as good as N95. So this is what I plan on using.

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So far I have 3D printed the prototype design on a FDM printer, and am using a nylon rope in place of the silicone gasket. The prototype only has roughly cut cotton layers right now, but it proves the design is both comfortable and seals very well.

I am still waiting some materials before I order the final 3D printed parts from Shapeways. The final parts will be made from Nylon which is dishwasher safe. It will also be much smoother and more durable than the PLA plastic the prototype is made from.

Even though it is custom fit to my face, it fit my wife quite well. This is many hours of work to design due to the complex curves involved. I ran into constant road blocks with the increasingly complex curves required to both make it fit, and be smooth on my skin.

[Vidar]

Interesting. There is a need for sure. Some masks seem kind of ok but doesn't actually work all that well. And those that do work is either hard to breathe through (small area of filtering) or rather bulky as you say. Some gas masks are quite comfortable, but they are on the bulky side. The GVS Elipse P100 is the most compact gas mask I got. While it fits inside a welding helmet or visor, and is quite ok to wear, it still looks out of place in a civil setting.

To make your modular design more universal and fit most people the face fitting part of it could be silicon and molded by the end user? That would reduce the need for 3D customization and instead substitute the end users actual face to make the final form fit. (Somewhat like one does for mouth guards in various contact sports).

The non filter parts would likely benefit from being made in materials that can withstand alcohol and or ozone for disinfection?

   

[ZapWizard]

So I have been living with my mask design for a few months now. I am glad I made it. It is comfortable to wear, even for hours. I can change the filters every day, and clean the frame with alcohol as needed.
I can take if off and leave it hanging on my chest , and putting it on takes just a second. I can easily adjust the tension on my face.

I altered the design so the magnets are now embedded in the gasket frame. It had to use a few more magnets due to them being thinner.

I added holes to allow me to stich the fabric in place if needed, but I didn't have to do that in the end. The fabric is just stretched around the front, then held in place by the magnetic force. The excess fabric ends up pleated on the inside providing extra filtration surfaces. Breathing isn't difficult due to the large surface area. My voice is attenuated compared to cheap masks. The perimeter seal stays solid, even when I talk.

I figured I would share some of the parts and materials I used for anyone wanting to do something similar.
The mask frame and vent pieces were 3D printed at Shapeways from SLS nylon. They can be 3D printed on a FDM machine, but are much weaker and not solid (harder to clean)
The front layer of fabric is a 4-way stretch denim. Basically a combination of 95% cotton and 5% spandex.
There is also an inner layer of 80% nylon / 20% spandex.
The magnets are small N52 magnets from McMaster.
The silicon foam gasket is also from McMaster
For the wrap around cord the best material I found is Silicone O-Ring stock. It is tough, stretchy, and easy to clean. I found normal elastic cord uncomfortable against my skin, and not easy to clean.
I used a elastic cord squeeze lock and ball end for the ends of the cord.

[pfrsantos]

Looks great. Glad you feel confortable with it.

 

Does it move out of place when you talk or open your mouth wider, like when yawning or so?

 

[ZapWizard]

The bottom side between my lip and chin, so it moves up and down as I talk, but doesn't loose seal. Ya, it would loose seal if I yawned.

[MadPlumbarian]

Nice job do you plan on making more of these?
I have my few that are just simple material and paracord, but I just started working on a steampunk one yesterday..
JR

[ZapWizard]

I have no plans on making them. The CAD design isn't easily adapted to different faces, I would have to start from scratch each time. The organic nature of the shapes also really taxed my CAD software and it crashed a lot.
If someone wants to pay big bucks, sure I am open to it, but these days folks think even custom items should be cheap.

[MadPlumbarian]

Oh I bet doing individual sizes would be costly, but maybe a universal?
JR