This week’s selection is the 3D printed Valved Snorkel by designer Robert Werner.
Werner is a prolific designer, having posted multiple unusual and complex designs to public forums. Several of his designs involve airflow, including a pollution meter, the snorkel described here, and even a ventilator valve.
One question that immediately comes to mind is this: “Why do you need a valved snorkel? Isn’t a snorkel just a curved pipe?”
Mostly it is, but there are a couple of problems with using just a simple pipe from the air above the water to your mouth for breathing. These can result in “Sudden Snorkel Death”, which Werner explains happens quite frequently in Hawaii.
One issue is that the water pressure increases slightly as the water depth is increased. This pressure differential increases the difficulty in pushing air, and while this is negligible for many people, some with less breathing ability can be affected.
The second problem is more insidious. If you look at the entire breathing system with a snorkel attached, you’ll see that the pipe adds an additional length to that path. And that means there is an additional volume of air to push out each breath. Imagine a short, inadequate breath: it would push “used” air up the pipe but not quite far enough to clear the end. Thus a second breath would simply reuse much of the previous breath!
This reduces the oxygen content and makes it harder to breathe, and then the swimmer must breathe more frequently, and then things can go wrong.
The answer is to use a valved snorkel, something used mostly by divers and professionals. The valve enables the snorkel to separate incoming and outgoing air to avoid this issue. That’s what this design is all about.
Valved Snorkel Design
Werner has provided two variations of the snorkel design. One uses a cheap, un-valved snorkel as the base for modification, and the other builds the entire snorkel from scratch.
The most complex part of the construction is the valve itself, which Werner designed in Autodesk Fusion 360.
Werner provides a set of detailed instructions on an Instructables entry, while the files themselves are stored publicly on Thingiverse for download at no charge.
3D Printed Snorkel In Action
Werner has successfully used the snorkel design, and but ran into some interesting issues. One related to the density of the parts. Depending on the amount of infill used, the parts may or may not float. This is important for recovery of lost items when in the water, as you want them to drop straight down instead of floating where they can drift to unknown distant locations.
Another issue was the thermal resistance of the materials. Werner found that on a hot beach PLA could begin deforming if the ambient temperature was too high and the snorkel was left in the sun. Perhaps PETG might be a better material for this design.
This could be an interesting design to work on while awaiting the arrival of summer.