I recently did two quick test dives, one in a bathtub and one in a pond. I noticed when testing in a bathtub I got about a half a teaspoon of water in each battery tube. This happened within 15 minutes when the openrov was floating on the surface of the water so I know this would get worse the deeper it went. For the second testdive in the pond I used clear rtv to seal the ends(i did this to just get another dive in).
I can see small cracks on the battery tubes. During the first assembly I couldn’t insert the endcaps without taking off the small edge on the ID of the tubes.
Following this comment,Comment 25 on Step 84, I used an exacto knife to carefully trim this lip. I think from inserting and removing the endcaps multiple times the chamfered edge created cracks that got larger and larger each time. I believe a tool to unscrew the endcaps would work better than rocking each side back and forth. This rocking motion could have made the cracks worse too.
I think it would be best to get new battery tubes and repot the ends. I guess I could solder the new potted ends to the old wires and use hot glue and heatshrink to keep water out of the soldered connection.
What are everyone’s thoughts and how do I order battery tubes and battery endcaps?
In the photo below note how the cracks go past where the oring seals.