Applying Thermal Lining To Rocket Tubes Requires A Monstrous DIY Spin-caster

September 2, 2025 by Donald Papp 18 Comments

[BPS.space] takes model rocketry seriously, and their rockets tend to get bigger and bigger. If there’s one thing that comes with the territory in DIY rocketry, it’s the constant need to solve new problems.

Coating the inside of a tube evenly with a thick, goopy layer before it cures isn’t easy.

One such problem is how to coat the inside of a rocket motor tube with a thermal liner, and their solution is a machine they made and called the Limb Remover 6000 on account of its ability to spin an 18 kg metal tube at up to 1,000 rpm which is certainly enough to, well, you know.

One problem is that the mixture for the thermal liner is extremely thick and goopy, and doesn’t pour very well. To get an even layer inside a tube requires spin-casting, which is a process of putting the goop inside, then spinning the tube at high speed to evenly distribute the goop before it cures. While conceptually straightforward, this particular spin-casting job has a few troublesome difficulties.

For one thing, the uncured thermal liner is so thick and flows so poorly that it can’t simply be poured in to let the spinning do all the work of spreading it out. It needs to be distributed as evenly as possible up front, and [BPS.space] achieves that with what is essentially a giant syringe that is moved the length of the tube while extruding the uncured liner while the clock is ticking. If that sounds like a cumbersome job, that’s because it is.

The first attempt ended up scrapped but helped identify a number of shortcomings. After making various improvements the second went much better and was successfully tested with a 12 second burn that left the tube not only un-melted, but cool enough to briefly touch after a few minutes. There are still improvements to be made, but overall it’s one less problem to solve.

We’re always happy to see progress from [BPS.space], especially milestones like successfully (and propulsively) landing a model rocket, and we look forward to many more.

Continue reading “Applying Thermal Lining To Rocket Tubes Requires A Monstrous DIY Spin-caster” →

Stripping GoPros To The Bone For Model Rocketry

December 1, 2024 by Danie Conradie 11 Comments

The small size of action cameras has made them a great solution for getting high-quality experimental footage where other cameras don’t fit. GoPros are [Joe Barnard]’s camera of choice for his increasingly advanced rockets, but even the smallest models don’t quite fit where he needs them. They also overheat quickly, so in the video after the break, he demonstrates how he strips and customizes them to fit his required form factor.

[Joe] starts out with a GoPro HERO10 Bones, which is a minimalist version intended for FPV drones. He likes the quality of the 4K 120 FPS video and the fact that he can update the settings by simply holding up a QR code in front of the camera. The case appears to be ultrasonically welded, so careful work with a Dremel is required to get it open. The reveals the control board with an aluminum heat sink plate, and the sensor module on a short ribbon cable. For minimal drag[Joe] wants just the lens to poke out through the side of the rocket, so he uses slightly longer aftermarket ribbon cables to make this easier.

The camera’s original cooling design, optimized for drone airflow, meant the device would overheat within 5 minutes when stationary. To increase the run time without the need for an external heat sink, [Joe] opts to increase the thermal mass by adding thick aluminum to the existing cooling plate with a large amount of thermal paste. In an attempt to increase heat transfer from the PCB, he also covers the entire PCB with a thick layer of thermal paste. Many of the video’s commenters pointed out that this may hurt more than it helps because the thermal paste is really intended to be used as a thin layer to increase the contact surface to a heat sink. It’s possible that [Joe] might get better results with just a form-fitting thermal block and minimal thermal paste.

[Joe] is permanently epoxying three of these modified cameras into his latest rocket, which is intended to fly at Mach 3, and touch space. This may look like a waste of three relatively expensive cameras, but it’s just a drop in the bucket of a very expensive rocket build.

We’ve seen GoPros get (ab)used in plenty of creative ways, including getting shot from a giant slingshot, and reaching the edge of space on a rocket and a balloon.

Continue reading “Stripping GoPros To The Bone For Model Rocketry” →

Rocket Mounted 3D Printed Camera Wheel Tries, Succeeds, And Also Fails

December 6, 2022 by Ryan Flowers 29 Comments

[Joe] at BPS.space has a thing for rockets, and his latest quest is to build a rocket that will cross the Kármán Line and launch into the Final Frontier. And being the owner of a YouTube channel, he wants to have excellent on-board video that he can share. The trouble? Spinning. A spinning rocket is a stable rocket, especially as altitude increases. So how would [Joe] get stable video from a rocket spinning at several hundred degrees per second? That’s the question being addressed in the video below the break.

Rather than use processing power to stabilize video digitally, [Joe] decided to take a different approach: Cancelling out the spin with a motor, essentially making a camera-wielding reaction wheel that would stay oriented in one direction, no matter how fast the rocket itself is spinning.

Did it work? Yes… and no. The design was intended to be a proof of concept, and in that sense there was a lot of success and some excellent video was taken. But as with many proof of concept prototypes, the spinning camera module has a lot of room for improvement. [Joe] goes into some details about the changes he’ll be making for revision 2, including a different motor and some software improvements. We certainly look forward to seeing the progress!

To get a better idea of the problem that [Joe] is trying to solve, check out this 360 degree rocket cam that we featured a few years ago.

Continue reading “Rocket Mounted 3D Printed Camera Wheel Tries, Succeeds, And Also Fails” →

Amateur Rocket Aims For The Kármán Line, One Launch At A Time

October 10, 2022 by Ryan Flowers 17 Comments

When it comes to high-powered rocketry, [BPS.space] has the unique distinction of being the first to propulsively land a solid-fueled model rocket. How could he top that? Well, we’re talking about actual rocket science here, and the only way is up! All the way up to the Kármán line: 100 km. How’s he going to get there? That’s the subject of the video below the break.

Getting to space is notoriously difficult because it’s impossible to fully test for the environment in which a rocket will be flying. But there is quite a lot that can be tested, and those tests are the purpose of a rocket that [Joe] at [BPS.space] calls Avalanche. Starting with a known, simple design as a test bed, numerous launches are planned in order to iterate quickly through several launches- three of which are covered just in this video.

The goal with Avalanche isn’t to get to the Kármán line, but to learn the lessons needed to build a far bigger rocket that will. A home-brewed guidance system, a gimballed spin-stabilized 4K camera, and the descent system are among those being tested and perfected.

Of course, you don’t have to be a rocket scientist to have fun with prototyping. Sometimes you just want to 3D print a detonation engine, no matter how long it won’t last. Why not?

Continue reading “Amateur Rocket Aims For The Kármán Line, One Launch At A Time” →

BPS.Space Succesfully Lands A Model Rocket

August 5, 2022 by Danie Conradie 16 Comments

If you’ve been following [Joe Barnard]’s rocketry projects for the past few years, you’ll know that one of his primary goals has been to propulsively land a model rocket like SpaceX. Now, 7 years into the rollercoaster journey, he has finally achieved that goal with the latest version of his Scout rocket.

Rocket touching down — We have touchdown!

Many things need to come together to launch AND land a rocket on standard hobby-grade solid fuel rocket motors. A core component is stabilization of the rocket during the entire flight, which achieved using a thrust-vectoring control (TVC) mount for the rocket motors and a custom flight computer loaded with carefully tuned guidance software. Until recently, the TVC mounts were 3D printed, but [Joe] upgraded it to machined aluminum to eliminate as much flex and play as possible.

Since solid-fuel rockets can’t technically be throttled, [Joe] originally tried to time the ignition time of the descent motor in such a manner that it would burn out as the rocket touches down. The ignition time and exact thrust numbers simply weren’t repeatable enough, so in his 2020 landing attempts, he achieved some throttling effect by oscillating the TVC side to side, reducing the vertical thrust component. This eventually gave way to the final solution, a pair of ceramic pincers which block the thrust of the motors as required.

Another interesting component is the landing legs. Made from light carbon fiber rods, they are released by melting a rubber band with nichrome wire and fold into place under spring tension. They also had to be carefully refined to absorb as much impact as possible without bouncing, which killed a few previous landing attempts.

Scrolling back through [Joe]’s videos and seeing the progress in his engineering is absolutely inspiring, and we look forward to his future plans. These include a functional scale model of the belly-flopping starship, a mysterious “meat rocket”, and the big one, a space shot to exceed 100 km altitude.

Continue reading “BPS.Space Succesfully Lands A Model Rocket” →

So Close To Landing A Model Rocket On Its Tail

November 27, 2020 by Danie Conradie 44 Comments

We’ve become so used to seeing SpaceX boosters land themselves back on the pad with clockwork reliability, that it’s easy to forget it took them a good number of attempts to get right. Inspired by SpaceX’s work, [Joe Barnard] of [BPS.Space] started working to replicate it at the model scale five years ago, with no engineering education or experience. On the latest attempt with a brand-new thrust vectoring Scout E rocket, he has gotten tantalizingly close to doing a controlled propulsive landing with a solid-fuel rocket motor.

We’ve all been thrilled to see the SpaceX rockets return to earth, landing elegantly on a floating pad. But those are liquid-fueled. The trick with a solid-fuel rocket motor is it can’t be throttled directly, which is a challenge when you need precision control to land. Thanks to [Joe]’s custom AVA flight computer and the remarkably consistent thrust curve of the Estes F15 black powder motors he used, it becomes a matter of igniting the descent motor at the right moment to make the vertical velocity zero at touchdown. However, [Joe] found that the time between sending the ignition signal and when peak thrust is reached was inconsistent, so he had to work around that. He did this by controlling how much of the thrust is spent in the vertical direction, by vectoring the motor side to side to spend some trust horizontally.

View from rocket of the ascent motor falling away immediately after being ejected

In this attempt, the rocket tipped over on landing due to excessive horizontal movement at touchdown. Joe tracked the cause down to a weak GPS signal caused by antenna position and a possible bug in the Kalman filter that fuses all the sensor data for position and velocity estimation. Thanks to incredibly detailed telemetry and logging done by the flight computer, data from every launch are used for future improvements. We are looking forward to the next flight in a few weeks, during which [Joe] plans to tune and test the control software, among other minor improvements.

Almost every single part of this rocket is a display of engineering ingenuity. The landing struts are designed to absorb as much impact as possible without bouncing while being light and quick to deploy. The ascent motor is ejected simply by moving the thrust vectoring mount to one of its extremes, allowing the descent motor to drop into place. The rocket also features a complete emergency abort system with a parachute, which can be activated manually, or by the flight computer if it calculates that landing isn’t feasible. We already covered [Joe]’s latest launch pad, which is a very interesting project all by itself.

Continue reading “So Close To Landing A Model Rocket On Its Tail” →

Advanced Model Rocket Flight Computer Reaching For The Stars

October 2, 2020 by Danie Conradie 15 Comments

When you’re building and launching a variety of advanced model rockets like [Joe Barnard], you don’t want to spend time building (and debugging) specialized flight computers for every rocket configuration. This challenge has led him to create AVA (All Vehicle Avionics), an impressive model rocket flight computer that he intends to use on all his future rockets.

All of [Joe]’s rockets feature active stabilization and guidance, and comprehensive telemetry using a variety of sensors. On the board there are three separate microcontrollers connected over I2C or SPI, each with its own micro USB port. The two smaller microcontrollers are both ATSAMD21s, also used on the Arduino Zero. The first is used for GPS and inertial navigation, and uses data from onboard and external sensors like the two IMUs (one is a backup), GPS and barometer to estimate the rocket’s position, velocity and attitude, The second is for telemetry, and it handles all external communications via a Bluetooth modem or long range 900 Mhz radio. The main processor (MPU) is a NXP MK20DX256 (also used on the Teensy 3.2), which receives data from the other microcontrollers and handles all the real-time operations and control outputs.

[Joe] gives a very detailed overview on the board, it’s capabilities, and the reasoning behind some of his design choices in the video after the break. Most of the sensors and microcontrollers were selected partly because of his experience with them. All three microcontrollers have Arduino bootloaders, also due to familiarity with the framework. AVA is the 12th in the line of flight computers [Joe] has built, and it is clear that a lot of work and hard-earned experience went into the design. Continue reading “Advanced Model Rocket Flight Computer Reaching For The Stars” →