After many weeks of careful construction and some small problems I finally got it all working and will be doing some open water dives. Here’s a sneak peak at my setup ready for another test dive. The ROV works well and the stability is incredible. The BlueRobotics team has put together something special here.
If you want a slightly smaller one, 3d printer fillament spools are that size, but narrower, and could be extended wider if you replace the center spindle. I have about 30 of them in a pile at the moment.
I got the pelican cases from Ebay. The tether reel is permanently attached to the case and I have made knotches on the case so the tether can pay out with the lid closed.