discussion / Biologging  / 12 October 2022

Water leakage in aquatic tags at deeper depths

Hi Folks

Does anyone have experience building their own aquatic tags? We are building a GPS-LoRa telemetry system. Although all the functions are working properly, we are having trouble with design. Water almost always leaks in, even at 20m depth. We are currently 3D printing the exterior.

Anyone else face these issues? What solutions did you employ? I will be grateful for further help regarding this.



What material are your 3D prints in and what printing technology are you using. I tried printing cases for terrestrial use in PLA. Even with an epoxy coating I was getting condensation forming inside my case. I'm still not certain if it was leaking in or was coming from moist air at the time of closure but in another thread some other Wildlabs members recounted similar problems with PLA.

Hi Hari,

We build various tags that need to work down to several thousand meters.

PLA is biodegradable, so whatever you do you'll end up with ingress if only using this alone. There are some waterproof SLS processes, but you will find condensation still prevents an issue. We use ABS or POM (CNC'ed) instead of 3D printing with o-ring seals for tags that are submerged for long periods of time, but for the ultimate solution you really want to pot your tags with a resin such as MG Chemicals 832WC - MG Chemicals and then break out a programming cable to some non conductive pins so you can still access the tag when potted inside the resin. You'll then not have to worry again.

Potting into PLA or an SLS 3D print works, so this could be the simplest route for you (i.e 3D print your enclosure and pot inside it once you've added the necessary breakout pins, or use bluetooth etc for comms and a reed switch to manage the tag once potted.

Hope this helps,