I got a new job at a startup this summer that has soaked up most of my time. That's not a bad thing because it is my dream job and I really like all my coworkers, but the clam project is my dream project, so I want to keep pushing forward. It's the nature of free software/open source projects that they are not profit driven and are dependent upon support from other things. I am hoping to find a better balance, so I can keep making progress.

I have passed two major milestones for my ability to contribute to this project. I have become a diver and gotten my open water certificate for scuba, and can now start working in the environments where the clams will be. I have also transitioned all of the design and fabrication of the clam to CAD and 3D printing. That is really important, so that I can test the clams without worrying too much about losing them. The first two prototypes I made with thermoforming, casting, hand cutting and finishing. I initially considered them more as works of art than prototypes, and was really sad when they burned out during testing. Now, I can print out a new design, test it, and keep moving forward when the clams are lost.

I have recently completed the first new 3D printed saturometer siphon and am beginning testing. It is essentially a gas collector and a water pump. The gas collector is made from a long length of silicone tubing. Silicone is gas permeable, so that if you have a thin enough membrane, and enough surface area, you can have a significant amount of gas pass through. An absolute pressure sensor is then used to measure the pressure of the gas in the tube, and give the total dissolved gas pressure.

The water pump is made from a silicone chamber and two valves. The valves are made from diaphragms taken from my air respirator, and 3D printed holders. Water flow is essential for getting an accurate pressure reading, so water needs to be pumped across the gas collector. This design is too big to fit into the clam, so it will need to be tested and miniaturized.