First build the one way valves. These silicon valves consist of a PLA housing with a central pin. A carefully cut round section of silicon sheet sits in this housing and is centered through a punch hole in its center. A tiny PLA nut is glued over this pin to hold the silicon valve sheet in place. The silicon valve works by having its edge carefully abut the rim of the valve seat and allowing its minimally supported central area to intermittently seal and open with the direction of the air flow. The roll of silicon has two protective layers on either side which should be removed. Cut squares of the material that will accommodate the size of the siliconCuttingForm. Place the silicon under the form and carefully outline on a good soft cutting surface with an 11 blade. You should have a good even circle. I also have an STl file for a cutting disc where I made a sharp edge and had some luck punching out a perfect ring of silicon on a concrete floor with a hammer--but this was hit or miss. Take the silicon disc and center it on the back of the valve housing and place a mark exactly in the center where the pin sits. Take a punch and punch a central 3.5 mm hole slightly larger than the pin in the silicon disc. Flip the valve over and place the silicon hole over the pin and make sure the disc fits perfectly around the margin. It must seal completely for it to work. Glue the ValveNut over the pin to hold the silicon disc in place. You can use either super glue or E6000. The trick is just to have the Nut sit on the silicon sheet--no attempt should be made to glue it to the silicon-- only to the pin. Don't get messy at this point. Repeat this process with the other valve seat. This sounds more difficult than it is, honestly I can make these valves in about 30 seconds.

Air flows through the valves from the flat side to the pin side. When they're glued you can test the valve polarity by blowing through them. Glue the inlet valve to the left side of the snorkel body. I use E6000 to get a watertight seal. Use just enough to seal the edge in and push it all the way in to the retaining ring position in the snorkel body. Don't over-glue which could cause dripping of glue onto the silicon valve and ruin it. Glue the exit valve on the right side of the valve body and seat it at the retaining ring. E6000 takes overnight to dry. Test out the polarity by breathing into the mouthpiece if everything was done correctly you should hear the valves click open and shut and air will be sucked in from the left and be expelled out the right. For the commercial snorkel build glue the inletTubeLargeSnorkelConventional.stl onto the inlet side with E6000 and either a FishFaceSnorkel.stl or nonFishExitCover.stl cover over the exit side. Take the silicon mouthpiece off the commercial snorkel and put it on your 3D printed body and remove the lower mouthpiece plastic section from the ribbed silicon tube and attach the 3D snorkel body in its place. Go out and Snorkel!