buoyancy

2 Articles

A model submarine is shown on a dock. The body of the submarine is made out of a series of acrylic tubes, with other parts made out of grey plastic.

3D-Printed Parts Nearly Sink RC Submarine

April 13, 2026 by 21 Comments

Of all the remote-control vehicles one can build, a submarine is possibly the hardest: if something goes wrong with almost any other vehicle, it’s easy to recover and repair, but a submarine is a very different affair. This nearly lost [James] of [ProjectAir] his latest project, a 2.7-meter long RC submarine, but it survived to make a few test sails.

Before building the full version, [James] made a test prototype. These submarines use large syringes as ballast tanks, pulling water in and out of the submarine body. The plungers are driven by a lead screw, and have a linear potentiometer for feedback. This can be wired in the same way as a servo motor, making it compatible with the RC controller. The controller receives its signal from an antenna in a buoy tethered to the submarine. Since initial tests worked well, [James] moved on to the full-scale model.

This was made out of radially-arranged acrylic tubes, with all but the top tube left open to the water. At the back of the submarine there were servo-actuated fins and a propeller, which would allow it to steer, ascend, and descend underwater. To waterproof the servo motors, [James] sealed them as much as possible, then filled them with oil. The other water-exposed electronics were either potted in epoxy or coated with a waterproofing compound. During testing, the submarine descended without issue, but was reluctant to resurface. Most of the external components had been 3D printed, and water infiltrated the infill below a certain depth. [James], however, managed to recover it before it was permanently lost, and managed to make a few other dives at a very limited depth.

On the other end of the spectrum from an RC submarine, we’ve also seen a rubber band-powered submarine. We’ve also seen a smaller, but more dive-ready RC submarine. Continue reading “3D-Printed Parts Nearly Sink RC Submarine” →

RC submarine surfaced in a pool

RC Submarine Build Starts With Plenty Of Research

August 13, 2024 by 19 Comments

[Ben]’s a 15-year-old who loves engineering and loves taking on new challenges. He’s made some cool stuff over the years, but the high water mark (no pun intended) has to be this impressively documented remote controlled submarine.

His new build starts off with more research than the actual building. [Ben] spent a ton of time investigating the design of the submarine from its shape, to the propeller system, to the best way to waterproof everything, keeping his sub in tip-top shape. He decides to go with the Russian-style Akula submarine, which is probably the generic look that most of us would think of when we hear the word submarine. He had some interesting thoughts on the propeller system (like the syringe ballast we’ve seen before), and which type of motor to use. In the end, he decided with four pumps that would act essentially as thrusters. fill a chamber with water, allowing the submarine to submerge, or fill with air, making the submarine buoyant, allowing it to resurface.

However, what we found most interesting about his build is how he explains the rationale for all his design decisions and clearly documents his thought process on his project page. We really can’t do [Ben]’s project justice in a short post, so head over to his project page to see it for yourself.

While you’re at it, check out some of these other cool submarine builds that we’ve featured here on Hackaday