Push core

Recently, I've been working in my lab to build samplers called push cores. They're clear plastic tubes that can be pushed into the seafloor to collect sediment samples. Usually, push cores are deployed by remotely operated vehicles (ROVs), but I wanted a smaller set that could be handled by SCUBA divers.

To get started, I wanted to gather reference images, so I searched "push core" online. What I got back was page after page of ab-blaster workouts and personal trainers. No, I do not want to push myself and build core strength, Google. Not what I meant! 

A set of push cores that I made

I was actually able to get the original drawings of WHOI's push core design from our machine shop, which helped a lot. I had to redesign the handles (which were supposed to be welded steel - I can't weld) and make sure the cores were small enough to fit inside a standard cooler so we can keep them cold during transits at sea. 

The good news about designing sampling gear for divers is that divers have much greater dexterity than an ROV. Even with thick gloves and tons of gear, a 10-fingered human beats a robot claw any day. I was actually able to simplify the design of the cores themselves and not worry about the increased complexity in using them because I know the divers can handle it. 

As I worked on the cores, it felt like for every step I did, there was another step that cropped up. I actually changed parts of the design as I went along, and on top of that, I had to request repairs for three different power tools (our belt sander dates from the 1960s). Box after box of supplies from McMaster-Carr showed up in my lab until I had found just the right sizes of everything. I cut, drilled, sanded, and assembled 27 cores plus the quivers to carry them in. One of the technicians in my department called my mess in the shop "colossal," but you know what, it was worth it.

In the end, I ended up with something that's pretty sleek. I look forward to using the push cores in the field!