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.
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Tesla’s last chance version of the flagship Model X is officially gone
The Signature Edition was no ordinary Model X Plaid. Offered exclusively by invitation to select existing Tesla owners, it represented the final production batch of the current-generation Model X before manufacturing at Fremont ends.
Tesla enabled a last-chance version of its two flagship vehicles, the Model S and Model X, over the past few weeks. The Model X, the company’s original SUV, is officially gone.
Tesla has officially closed the book on its most exclusive send-off for the Model X. The limited-run Model X Signature Edition—priced at $159,420 before fees and limited to just 100 units—is now sold out, with reservations closed as of April 16.
The $160,000 Model X Signature Edition is officially sold out.
Reservations are now closed. pic.twitter.com/4D5FSkTZTa
— Sawyer Merritt (@SawyerMerritt) April 16, 2026
The Signature Edition was no ordinary Model X Plaid. Offered exclusively by invitation to select existing Tesla owners, it represented the final production batch of the current-generation Model X before manufacturing at Fremont ends.
Every unit featured an exclusive Garnet Red exterior paint, unique badging, and a standard six-seat configuration. With full Plaid powertrain specs—Tri-Motor All-Wheel Drive, over 1,000 horsepower, and blistering acceleration—it was positioned as a collector’s item for loyalists who wanted one last shot at owning a piece of Tesla history.
The timing is no coincidence.
Tesla announced earlier this year that it would discontinue regular production of both the Model S and Model X to repurpose the Fremont factory’s dedicated lines for mass production of its Optimus humanoid robots.
Elon Musk has repeatedly emphasized that Optimus could ultimately become more valuable to the company than its vehicle business, with ambitions to build hundreds of thousands of units annually.
The Signature Editions served as a final “runout” series: 250 for the Model S and only 100 for the Model X, all built to the highest Plaid specification before the line is converted.
Deliveries of the remaining Signature units are scheduled to begin in May 2026. For buyers who secured one, it’s the ultimate swan song for a vehicle that helped define Tesla’s early luxury EV dominance.
Launched in 2015, the Model X introduced falcon-wing doors, a panoramic windshield, and class-leading performance that turned heads and set benchmarks. While newer models like the Cybertruck and refreshed Model Y have taken center stage, the Model X Plaid remained a halo product for those seeking maximum range, space, and speed in an SUV package.
With inventory of standard Model X units already nearly exhausted across the U.S., the rapid sell-out of the Signature Edition underscores enduring demand for Tesla’s premium flagships even as the company pivots toward robotics and autonomy.
For enthusiasts, these 100 garnet-red SUVs will likely become instant collector’s items—tangible reminders of the vehicles that built the brand before Tesla’s next chapter fully begins. The last chance is gone, but the legacy endures.
Elon Musk
Tesla Optimus V3 hand and arm details revealed in new patents
Two new patents, which were coincidentally filed on the same day as the “We, Robot” event back in October 2024, protect Tesla’s mechanically actuated, tendon-driven architecture.
Tesla is planning to soon reveal its latest and greatest version of the Optimus humanoid robot, and a series of new patents for the hands and arms, with the former being, admittedly, one of the most challenging parts of developing the project.
Two new patents, which were coincidentally filed on the same day as the “We, Robot” event back in October 2024, protect Tesla’s mechanically actuated, tendon-driven architecture.
The designs relocate heavy actuators to the forearm, route cables through a sophisticated wrist design, and employ innovative joint assemblies to achieve human-like dexterity while enabling lightweight construction and high-volume manufacturing.
Core Tendon-Driven Hand Architecture
The primary patent, which is titled “Mechanically Actuated Robotic Hand,” details a cable/tendon-driven system.
Actuators are positioned in the forearm rather than the hand. Each finger features four degrees of freedom (DoF), while the wrist adds two more.
Tesla’s Optimus V3 robot hand looks to have been revealed in a new international patent published today.
The patent describes a tendon/cable-driven hand:
• Actuators in the forearm
• Each finger has 4 degrees of freedom
• The wrist has 2 degrees of freedom
• Tendon-driven… pic.twitter.com/eE8xLEYSrx— Sawyer Merritt (@SawyerMerritt) April 16, 2026
Three thin, flexible control cables (tendons) per finger extend from the forearm actuators, pass through the wrist, and connect to the finger segments. Integrated channels within the finger phalanges guide these cables selectively—routing behind some joints and forward of others—to enable independent bending without unintended motion.
Patent diagrams illustrate thick cable bundles emerging from the wrist into the palm and fingers, with labeled pivots and routing guides. This setup closely mirrors human forearm-muscle and tendon anatomy, where most hand control originates proximally.
Advanced Wrist Routing Innovation
One of the standout features is the wrist’s cable transition mechanism. Cables shift from a lateral stack on the forearm side to a vertical stack on the hand side through a specialized transition zone.
Boom! @Tesla_Optimus 의 3세대 구조로 추정되는, 로봇 팔 및 관절에 대한 특허가 공개되었습니다.
아티클 작업에 들어가겠습니다.
1년 넘게 기다려 온, 정말 귀한 특허인데, 조회수 100만대로 터져줬으면 좋겠네요. 😉@herbertong @SawyerMerritt@GoingBallistic5 @TheHumanoidHub pic.twitter.com/CCEiIlMFSX
— SETI Park (@seti_park) April 16, 2026
This geometry significantly reduces cable stretch, torque, friction, and crosstalk during combined yaw and pitch wrist movements — common failure points in simpler tendon systems that cause imprecise or jerky motion.
By minimizing these issues, the design supports smoother, more reliable multi-axis wrist operation, essential for complex real-world tasks.
Companion Patents on Appendage and Joint Design
Two supporting patents provide additional depth. “Robotic Appendage” covers the overall forearm-to-palm-to-finger assembly, with a palm body movably coupled to the forearm and finger phalanges linked by tensile cables returning to forearm actuators. Tensioning these cables repositions the phalanges precisely.
“Joint Assembly for Robotic Appendage” describes curved contact surfaces on mating structures paired with a composite flexible member. This allows smooth pivoting while maintaining consistent tension, enhancing durability, and simplifying assembly for mass production.
Executive Insights on Hand Development Challenges
Tesla executives have consistently described the hand as the most difficult component of Optimus.
Elon Musk has called it “the majority of the engineering difficulty of the entire robot,” emphasizing that human hands possess roughly 27–28 DoF with an intricate tendon network powered largely by forearm muscles. He has likened the challenge to something “harder than Cybertruck or Model X… somewhere between Model X and Starship.”
In mid-2025, Musk acknowledged that Tesla was “struggling” to finalize the hand and forearm design. By early 2026, he stated that the company had overcome the “hardest” problems, including human-level manual dexterity, real-world AI integration, and volume production scalability.
He estimated the electromechanical hand represents about 60 percent of the overall Optimus challenge, compounded by the lack of an existing supply chain for such precision components.
These patents directly tackle the acknowledged pain points: relocating actuators reduces hand mass and inertia for better speed and efficiency; advanced wrist routing and joint geometry address friction and crosstalk; and simplified, stackable parts visible in the diagrams indicate readiness for high-volume manufacturing.
Implications for Optimus Production and Leadership
Collectively, the patents portray the Optimus v3 hand not as a mere prototype, but as a production-oriented system engineered from first principles.
The 22-DoF architecture, forearm-driven tendons, and crosstalk-minimizing wrist deliver a clear competitive edge in dexterity. They align with Musk’s view that high-volume manufacturing is one of the three critical elements missing from most other humanoid projects.
For Optimus to become the most capable humanoid robot, its hand needed to replicate the useful and applicable design of the human counterpart.
These filings demonstrate that Tesla has transformed years of engineering challenges into patented, elegant solutions — positioning the company strongly in the race toward general-purpose robotics.
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Tesla intertwines FSD with in-house Insurance for attractive incentive
Every mile logged under FSD now carries a documented financial value—lower risk, lower cost—based on Tesla’s internal driving data rather than external crash statistics alone.
Tesla intertwined its Full Self-Driving (Supervised) suite with its in-house Insurance initiative in an effort to offer an attractive incentive to drivers.
Tesla announced that its new Safety Score 3.0 will automatically have a perfect score of 100 with every mile driven with Full Self-Driving (Supervised) enabled.
The change is designed to boost customers’ average safety scores and deliver noticeably lower monthly premiums.
The move marks the clearest link yet between Tesla’s autonomous driving technology and its proprietary insurance product. Tesla Insurance already relies on real-time vehicle data—such as acceleration, braking, following distance, and speed—to calculate a Safety Score between 0 and 100. Higher scores have long translated into cheaper rates.
Under the previous system, however, even brief manual interventions could drag down the average, frustrating owners who rely heavily on FSD. Version 3.0 eliminates that penalty for supervised autonomous miles, effectively treating FSD-driven segments as the safest possible driving behavior.
The incentive is immediate and financial. Drivers who keep FSD engaged for the majority of their trips will see their overall score rise, potentially shaving hundreds of dollars off annual premiums.
Tesla framed the update as a direct response to customer feedback, many of whom had complained that the old scoring model punished the very behavior it was meant to encourage.
For now, the program applies only to new policies in six states: Indiana, Tennessee, Texas, Arizona, Virginia, and Illinois.
Existing policyholders are not yet included, a point that drew swift questions from the Tesla community. Many owners in other states, including California and Georgia, expressed hope that the benefit would expand nationwide soon.
The announcement arrives as Tesla continues to roll out FSD Supervised updates and push for regulatory approval of more advanced autonomy. By tying insurance savings directly to FSD usage, the company is putting its own actuarial weight behind the technology’s safety claims.
Every mile logged under FSD now carries a documented financial value—lower risk, lower cost—based on Tesla’s internal driving data rather than external crash statistics alone.
Tesla has not disclosed exact premium reductions or the full rollout timeline beyond the six launch states.
Still, the message is clear: the more drivers trust FSD Supervised, the more Tesla Insurance will reward them. In an era when legacy insurers remain cautious about autonomous tech, Tesla is betting that its own data will prove the safest miles are the ones driven hands-free.