Full Face Snorkeling Mask Respirator Filter Conversion

thingiverse

<h3>Design history</h3> During the summer of '19 Henry Alfredo pioneered converting a snorkel diving mask into a gasmask: https://www.instagram.com/p/BzDeL8WoGLT/ Now during the Wuhan Virus craze i'm happy to see many people also discovered the other use of snorkel masks. Companies seemed to have filed for patents since the start of 2020 yet i'm pretty sure i've established prior art. I publicized the design so people can lower their full face respirator costs and refill their own cartridges. This design began as a way to replace my used GP-5 gasmask filters. As such can be directly screwed on the GP-5 mask. This so called ГОСТ 8762-75 (interstate standard) is a 40mm thread type with a 4mm thread pitch. Have used the 3d printed filter with new activated carbon extensively during spray painting indoors. <h3>Design updates</h3> DOP_4 is preferred over DOP_3. Added a chamfer for comfort. Removed the inner seating ridge for the 5/4" rubber for a cleaner print. CAP_4 is the preferred bottom screw cap after printing it in 200 microns. It also has chamfered edges. CAP_3 is a too tight fit. CAP_2 is a bit too loose. Kept them included in case you need a tighter/looser fit depending on your outcome. <h3>Convert your snorkeling mask into a respirator.</h3> Filter has a substantial volume which you can fill with any material at hand. Note that activated carbon doesn't filter out viruses. Rubber 5/4" gasket ensures airtight seal. This is commonly available at the hardware store. I've already made an adapter which fits to the noname brand snorkeling mask, will make one for the Decathlon mask soon. <h3>Printing instructions(WIP)</h3> Preferably print in ABS and seal with acetone to keep all parts clean and airtight. CAP_4 has a tendency to warp in ABS so add at least a 5-7mm brim. All parts with threads preferably are printed in 200 micron layers heights. The rest can be printed in 300 microns (although 200 is better). No support needed on any part. FILTER_DOP_4 ideally should be printed in TPU. <h3>Assembly instructions (WIP)</h3> Drop some acetone into CAP_4 and roll it around near the threaded edge, brushing excess acetone along the threads. Same goes for DOP_4. After you have used acetone to join the threads and sealed all the prints, leave it for an hour at least to dry. Don't try to acetone two sides of a print at once it will leave ugly fingermarks. If GASMASKER_FILTER_5 and CAP_4 encounter a lot of friction inspect and trim away the base of GASMASKER_FILTER_5 where elephant feet created unwanted threading. After drying screw DOP_4 and CAP_4 on and off repeatedly until no chafings are coming off. Treat the threaded side again with acetone. This seals the print and strengthens the screw thread. The bottom seal relies on pressing your filter material underneath AFTEKEN_RING_3 against GASMASKER_FILTER_5 by screwing it together with CAP_4, friction keeps it in place. AFTEKEN_RING_3 doubles as a template to cut filter material to size. MESH_BOTTOM_1 and MESH_4 should be inserted with the rim facing the user. Add scotch tape to MESH_4 as a pull tab for easier removal. <h3>Viral Filter concept</h3> Still researching. If you aren't sure your HEPA vacuum cleaner bag is safe, don't use it. https://smartairfilters.com/en/blog/best-materials-make-diy-face-mask-virus/ https://smartairfilters.com/en/blog/paper-towel-effective-against-viruses-diy-mask/ https://smartairfilters.com/en/blog/diy-homemade-mask-protect-virus-coronavirus/ https://www.consumer.org.hk/ws_en/news/2020/covid-19-diymasks?fbclid=IwAR3kJO1b4vFGtmijvE_sRvVUN7OHaX1YyiGnJNYkAE9zd49SlJ0A0_RPVVo https://www.businessinsider.nl/homemade-mask-using-hydro-knit-shop-towel-filters-better-2020-4?international=true&r=US <h3>Sanitation instructions(WIP)</h3> An one hour 65°C dishwasher cycle on ABS parts works fine. Parts in ABS probably won't hold in autoclave temperatures >90°C due to deformation. It seems ABS doesn't tolerate bleach very well so the dishwashing machine or hand-washing with soap and water is the recommended approach. Clean all parts thoroughly before inserting new filter material. Preferably store in a sealed bag when not in use. <h3>Disclaimer</h3> Use at own risk. Depending on the pressure drop of how you stuffed the filter usage duration should be limited. Advised not to use it alone.