Because I have been rebuilding parts of my ROV due to the blow-up of my original ESC design, I've taken the opportunity to reduce the size of the tubes which house the electronics and cameras. When I started out, I had no real understanding of how much space these two systems would take, nor how buoyant two large, mostly empty, tubes of air would be. The counter this buoyancy I've had to add more weight; and that just makes the whole thing heavier for nor real gain.

So, I've replaced the original Blue Robotics tubes with custom sized Blue Robotics tubes (195mm each - a reduction of about 1/3 on the default tube size).

You can see the tubes below, both before and after install. I've also removed one of the 1 pound lead weights in anticipation of re-adjustting the buoyancy - once I finally get it back in the pool.

One of the nice side effects of reducing the tube size is that I can now fit the top thrusters inside the cubic frame rather than having them perched on the top (you can just see one of them on the right/middle). I much prefer the ascetics of this, and it also makes the top surface far less fragile.