A recent episode of Sandy Munro’s Tesla Model Y teardown series has revealed that the electric car company utilized friction stir welding (FSW) for the crossover’s thermal management system. The welding technique is commonly used among aerospace companies, like SpaceX, as a way to maintain the strength of aluminum parts while securing a reliable bond between pieces.
Munro’s analysis of the Octovalve coolant system revealed Tesla’s techniques for the revised thermal management portion of the Model Y. Munro discovered the Octovalve on April 4 after digging into the Model Y’s internal build. The new coolant assembly seemed to be a revised version of the Model 3’s “Superbottle,” which served as the heart of the sedan’s thermal management system.
A car’s thermal management apparatus is responsible for controlling and maintaining proper temperatures in critical portions of the vehicle. In the case of the Model Y, the Octovalve is responsible for motor, battery, and cabin cooling, according to Munro. The Detroit auto veteran said that typically, these systems should not be cooling the cabin if they are controlling battery or motor temperature. The thermal management system in the Model Y seems to be controlling the cabin, the battery, the electronics, and the motor nonetheless.
The Octovalve seems to be a state-of-the-art system as it uses, “some clever little ball valves that open and close to make sure that everything’s getting heated or everything’s being cooled to where it needs to be,” Munro said.
With the assembly overlooking the temperature for these many parts of the vehicle, the system is subjected to drastic and sharp temperature changes. Over time, the difference between heat and cold can begin to weaken portions of the car part, especially if it was exposed to excessive temperatures during manufacturing. This is where some SpaceX-grade solutions come into play.
Tesla chose to utilize friction stir welding for its aluminum portions of the coolant assembly. “This is a cool way of putting two parts of aluminum together, some other materials as well, but aluminum is kind of the most suited for it. And in essence, what happens is you have a stylus that spins around very very quickly. It pokes through the two pieces of metal that you want to friction stir weld. Then, it goes around the outside edge, and what it does is it uses the plastic state or thixotropic state of the aluminum to bind it together,” Munro said.
Simply put, the process allows aluminum to reach a temperature that allows two pieces of metal to come together with a strong bond, but it never turns the metal into a soft, liquid-like state. “It’s like soft butter, butter that you could see is firm, but you could cut it with a knife.”
The advantage of using this process is that the heat from the welding process only applies to the outer edges of the metal. The additional material that is not bonded to anything does not see the heat and is not weakened by the welding process. Stir welding is also time effective as it can be completed in a short period, but it is a careful process that does not apply unneeded stress upon the rest of the assembly.
SpaceX uses friction stir welding for its rockets, as it increases strength by exposing only the bonded portions of two pieces of metal to each other. Friction stir welding was used by SpaceX back in 2008 when the company was combining barrel sections of the Falcon 9’s second stage. “The FSW joins metal without flames, sparking, inert gasses, or fumes, and produces a far superior weld in aluminum-lithium alloys as compared to traditional methods,” SpaceX said in a news update.
In the spirit of humor, Tesla and Elon Musk saw the Octovalve as a perfect opportunity to not only improve the performance of the vehicle temperature regulation system but also as an appropriate time to sprinkle in some additional humor in the form of an Easter Egg. The Model 3 donned a cape-wearing bottle-figured superhero for its “Superbottle” system, while the Model Y includes a snowflake-stamped Octopus as an Easter Egg.
Tesla has increased the effectiveness of its thermal management with the introduction of the Model Y’s Octovalve system. Elon Musk stated that it was some of the best engineering he had ever seen. The welding process could increase the longevity of the machine through its lack of exposure to excessive heat and stress during manufacturing.
Watch Munro’s video on the Model Y’s Octovalve welding below.
Tesla (NASDAQ: TSLA) is set to hold its Earnings Call for the first quarter of 2026 on Wednesday, and there are a lot of interesting things that are swirling around in terms of speculation from investors.
With the company’s executives, including CEO Elon Musk, answering a handful of questions that investors submit through the Say platform, fans want to know a lot of things about a lot of things.
These five questions come from Retail Investors, who are normal, everyday shareholders:
- When will we have the Optimus v3 reveal? When will Optimus production start, since we ended the Model S and Model X production earlier than mid-year? What’s the expected Optimus production rate exiting this year? What are the initial targeted skills?
- What milestones are you targeting for unsupervised FSD and Robotaxi expansion beyond Austin this year, and how will that drive recurring revenue?
- How will Hardware 3 cars reach Unsupervised Full Self-Driving?
- When do you expect Unsupervised Full Self-Driving to reach customer cars?
- When will Robotaxi expand past its current limited rollout?
Additionally, these are currently the three questions that are slated to be answered by Institutional Firms, which also answer a handful of questions during the call:
- Now that FSD has been approved in the Netherlands and is expected to launch across Europe this summer, can you discuss your Robotaxi strategy for the region?
- What enabled you to finish the AI5 tapeout early and were there any changes to the original vision? Last week, Elon said AI5 will go into Optimus and the Supercomputer, but one month ago said it would go into the Robotaxi. Has AI5 been dropped from the vehicle roadmap?
- Given the recent NHTSA incident filings, can you update us on the Robotaxi safety data? If safety validation remains the primary bottleneck, why not deploy thousands of vehicles to accelerate the removal of the safety driver?
The questions range through every current Tesla project, including FSD expansion and Optimus. However, many of the answers we will get will likely be repetitive answers we’ve heard in the past.
This is especially pertinent when the questions about when Unsupervised FSD will reach customer cars: we know Musk will say that it will happen this year. Is Tesla capable of that? Maybe. But a more transparent answer that is more revealing of a true timeline would be appreciated.
Hardware 3 owners are anxiously awaiting the arrival of FSD v14 Lite, which was promised to them last year for a release sometime this year.
The Earnings Call is set to take place on Wednesday at market close.
Elon Musk
Elon Musk reveals shocking Tesla Optimus patent detail
What looked promising on paper and in simulations failed to deliver the reliability required for a robot expected to handle delicate tasks like folding laundry, assembling electronics, or assisting in factories and homes.
Elon Musk revealed a shocking detail on the Tesla Optimus patent that was revealed last week. Despite it being made public for the first time, Musk said the company has already moved on from the design, an incredible truth about the development of new technology: things move fast.
Musk dropped a bombshell about the Tesla Optimus humanoid robot hand patent that was released last week. Musk, candidly replying to a post late at night on X, revealed that what is a new technology to many fans and insiders is actually old news to those developing the tech directly.
“We already changed the design,” Musk said. “This one didn’t actually work.”
We already changed the design. This one didn’t actually work.
— Elon Musk (@elonmusk) April 19, 2026
Patents, after all, are often viewed as blueprints for future products. Yet Musk revealed that the rolling contact mechanism—intended to provide smooth, low-friction articulation in the fingers—had already been scrapped after real-world testing exposed its shortcomings.
What looked promising on paper and in simulations failed to deliver the reliability required for a robot expected to handle delicate tasks like folding laundry, assembling electronics, or assisting in factories and homes.
The hand has been one of the biggest challenges for Tesla engineers since Optimus development started years ago. Musk has said that there is not enough recognition for how incredible and useful the human hand is, and designing one for a humanoid robot has been the biggest challenge of all.
Tesla is stumped on how to engineer this Optimus part, but they’re close
This moment underscores the persistent engineering hurdles in achieving reliable humanoid hand dexterity. Human fingers are marvels of evolution: 27 bones, intricate tendons, ligaments, and a network of sensors working in perfect harmony. Replicating that in metal and silicon is extraordinarily difficult.
Rolling contacts promised reduced wear and precise motion, but testing likely revealed issues with durability under repeated stress, grip stability on varied surfaces, or the micro-precision needed for fine motor skills.
These aren’t minor tweaks, but instead they represent fundamental challenges that have plagued robotics teams for decades. Even advanced competitors struggle here—hands remain the Achilles’ heel of most humanoids because the margin for error is razor-thin.
A fraction of a millimeter off, and a robot drops a glass or fails to button a shirt.
What makes Musk’s reply remarkable is how it signals Tesla’s direct communication style on prototype limitations. While many companies guard failures behind glossy marketing and vague timelines, Tesla openly shares setbacks.
Musk was forthcoming about the failure of this recent design. This transparency builds trust with investors, engineers, and fans. It shows Tesla treats Optimus development like true science: rapid iteration, rigorous testing, and zero tolerance for hype that doesn’t match reality.
The disclosure from Musk also highlights Tesla’s blistering pace of development. By the time the patents are published, which is often over a year after the initial filing, the technology has already evolved.
Optimus is far from a static product, and it’s a living project advancing weekly.
In the high-stakes race for general-purpose robots, Tesla’s approach stands out. Admitting a finger-joint design “didn’t actually work” isn’t a weakness—it’s confidence.
True innovation demands confronting failure head-on, and Musk just reminded the world that Optimus is being engineered that way. The next version of those hands is already in testing, and it will be better because Tesla isn’t afraid to say what didn’t work.
Elon Musk
Tesla is sending its humanoid Optimus robot to the Boston Marathon
Tesla’s Optimus robot is heading to the Boston Marathon finish line
Tesla’s Optimus humanoid robot will be stationed at the Tesla showroom at 888 Boylston Street in Boston, right along the final stretch of the Boston Marathon today, ready to cheer on runners and pose for photos with spectators.
According to a Tesla email shared by content creator Sawyer Merritt on X, Optimus will be at the Boston Boylston Street showroom on April 20, coinciding with Marathon Monday weekend. The Boston Marathon finishes on Boylston Street, and the surrounding area draws hundreds of thousands of spectators along with international broadcast coverage. Placing Optimus there puts it in front of a massive public audience at zero advertising cost.
Just got this email. @Tesla’s Optimus robot is coming to Boston.
“Join us from April 19 to 20, 2026, at Tesla Boston Boylston Street showroom to meet Optimus, our humanoid robot, for Marathon Monday. Optimus will be cheering with you on the sidelines and posing for photos.” pic.twitter.com/chxoooO2xV
— Sawyer Merritt (@SawyerMerritt) April 18, 2026
The Tesla showroom is at 888 Boylston Street, between Gloucester Street and Fairfield Street. The final mile of the marathon runs directly along Boylston Street, with runners passing the big stores before reaching the finish line at Copley Square.
Optimus was first announced at Tesla’s AI Day event on August 19, 2021, when Elon Musk presented a vision for a general-purpose robot designed to take on dangerous, repetitive, and unwanted tasks. In March 2026, Optimus appeared at the Appliance and Electronics World Expo in Shanghai, where on-site staff stated that mass production of the robot could begin by the end of 2026. Before that, it showed up at the Tesla Hollywood Diner opening in July 2025 and at a Miami showroom event in December 2025.
Tesla’s well-calculated display of Optimus gives the public a low-pressure first encounter with a robot that Tesla is preparing to soon deploy at scale. The company has previously indicated plans to manufacture Optimus robots at its Fremont facility at up to 1 million units annually, with an Optimus production line at Gigafactory Texas targeting 10 million units per year.
Tesla showcases Optimus humanoid robot at AWE 2026 in Shanghai
Musk has said that Optimus “has the potential to be more significant than the vehicle business over time,” and separately that roughly 80 percent of Tesla’s future value will come from the robot program. Whether that holds depends on production execution. For now, Boston gets a preview of what that future looks like, standing at the finish line on Boylston Street while 32,000 runners pass by.
Tesla Q1 Earnings: What Elon Musk and Co. will answer during the call
Elon Musk reveals shocking Tesla Optimus patent detail
