The Tesla Cybertruck has received tons of criticism for the build quality of its edgy, stainless-steel body, with loads of car websites ripping on prototypes and Elon Musk himself reportedly voicing his displeasure and mandating strict LEGO-like build quality standards. So it’d make sense if you’re curious how the truck is built, and how those mandates are followed; the good news is that manufacturing experts at Munro & Associates have gotten an exclusive tour of the Cybertruck’s body stamping factory. Here’s what they saw.
The stainless steel exterior panels of the Cybertruck are one of its prime standout features, though construction presents some engineering challenges. With no coatings or paint on the panels, the stainless steel must be as corrosion resistant as possible. This requires careful selection of material, as not all stainless steels are as stainless as you might hope. Beyond that, the fabrication process must not mark the panels in the slightest, as there are no layers of primer and paint to hide these sins. To show and explain how Tesla conquered these problems, Munro gets a tour from Lars Moravy, the VP of Vehicle Engineering at Tesla. Along with Moravy’s commentary, we’re treated to insights from a number of Tesla plant crewmembers who stayed back after-hours to share their knowledge. Access like this isn’t something you get every day, either. Some automakers strictly limit even their own employees from sharing video or photography from inside a plant to protect their accumulated manufacturing knowledge. St52 Pipe
Tesla uses a custom stainless steel alloy for the Cybertruck. It’s referred to as Hard Freaking Stainless, or HFS (yes, really). It was formulated to be hard and highly corrosion resistant while still maintaining enough ductility to be readily formable during manufacturing. As we’re shown in the video, Tesla receives HFS not as flat sheets, but on giant rolls. These must first be unrolled and flattened out before following manufacturing operations can begin.
This is all achieved on a laser blanking line which Tesla developed with Schuler. After the large rolls of stainless steel are uncoiled, they pass through rollers that act as straighteners. This works out any residual internal stresses in the material that would want to keep the material in its curved, coiled state. The process requires finesse, as overdoing things at this stage can “work harden” the material, which would cause it to fail in the bending processes later (a metal’s ability to bend is important when you’re forming it).
Once flattened, the sheets of stainless steel are cut into blanks using a pair of lasers. Moravy notes that they are currently achieving roughly 80% utilization of the panels. That’s a pretty solid figure, with the rest sent to the line’s dedicated stainless steel scrap collection. A lot of that is down to the shape of the Cybertruck’s panels, which are fairly square, making them easy to nest, Moravy notes. It’s also supported by the fact that the rolls of stainless steel are sized to the specific parts being produced, which also helps reduce wastage.
Once cut, the blanks are carefully stacked by machine, with Moravy explaining that it’s a delicate process. The stainless parts are naturally hard enough to scar each other, so they have to be placed down gently without scuffing or rubbing against each other, causing defects. As Munro notes, it’s typical to cut such parts with a plastic coating on to avoid minor scratches and damage during handling, but Tesla doesn’t do that here. With no coatings, there is naturally less waste and no need to add the step of peeling it off at some point during the production process.
We’re also filled in on the thickness of the stainless steel used in the Cybertruck’s panels. The doors are 1.8 mm thick, or roughly 0.07 inches thick. The other panels are thinner, at 1.4 mm (0.055 inches). Engineering efforts during the development of the Cybertruck were key to slimming the required thickness down. “We worked hard to get that strength up on the stainless,” explains Moravy. “The original, we were about 2.5, 3 [millimeters thick]… we actually increased the strength of HFS over time.”
Periodic quality checks are carried out on the blanks using a 2D scanner. The camera or machine vision component appears to be mounted quite high above the scanning bed, such that we don’t see it in the video. The outline of the flat blank is compared to a digital template and the system shows markers at various points indicating compliance. It’s a key tool for the team to ensure that panels are being produced to the exact right dimensions, because if the blanks are off, the final parts will be as well.
Next up, we’re treated to a look at one of the dies used to stamp the inner panels for the front doors. Each door is made up of the flat stainless steel outer, which forms the outside body of the car, and an inner panel that adds structure and serves to mount the interior trim and hardware. “Forming stainless as an A surface is kind of hard because you get drag marks and what not, so we had to work really hard on this process as well” explains Moravy. For those outside the automotive business, a Class A surface basically refers to interior touch points and exterior panels that must have absolutely top-tier surface finish and aesthetic quality. On a normal car, paint and finishing would hide many flaws, but the all-stainless construction of the Cybertruck doesn’t allow that.
As you might expect, the stamping die looks pristine, with visibly smooth and shiny surfaces. That’s no surprise, because whether you’re stamping or casting something, the part’s surface finish can only be as good as the die’s surface finish. Thus, to produce high-quality stamped parts that look nice and flat and shiny, you need a die with excellent surface finish just the same.
The die inserts are made with an aluminum bronze alloy on its as this allows the production of stainless steel parts with minimum to no drag marks. The inserts are hardened and have a coating on top to give them the best possible longevity. Aluminum and its alloys aren’t really the most hard-wearing materials for constructing press tooling, but it’s a necessary compromise here to produce mark-free parts. It’s also explained that Tesla is still experimenting with different lubricants for the press process for the best possible results.
Munro is amazed the aluminum bronze is being used for stamping , but Moravy explains that it’s working well given the constraints. “When you use steel we get drag marks, [but] you know aluminum can’t last, right?” says Moravy. “So we obviously have to replace these inserts a reasonable amount of time but they’re lasting quite a longer than we thought they would.” At this stage, the plant has only run around 1,000 to 1,200 stamps for each part. “I think we’re gonna get about, based on our prototype trials, anywhere from 50 to 100 before we start doing rework” says Moravy. An engineering interpretation would suggest he means 50,000 to 100,000 stamps, not merely 50 to 100. If it were just 50 to 100, there’d be no way to build the Cybertruck in real numbers as the press tools would be getting serviced every few hours.
All in all, it’s clear Tesla has done some novel engineering on the manufacturing side. “I’ve never really stamped stainless steel without a coating” says Munro. “I don’t think anyone has,” replies Moravy. “Certainly not for an A-surface quality part.” Without checking every plant in the world, we can’t verify this, but stainless stamping for automotive isn’t exactly common, regardless.
We next get to see the hot stamp process, which produces the door rings (or “body side inners”) for the Cybertruck chassis. The line has three furnaces each with seven chambers, which can heat 21 blanks at a time ready to be pressed. The blanks are heated up to 900°C (1652°F) before they are plucked out by a robot and put in the press. The press brings the upper and lower dies together, and holds them in place for around 6 to 8 seconds, with water running through the dies to help quench the part. The parts are then ideally unloaded into racks automatically by a robotic racking system, but it’s not quite implemented yet. The video of this process is only compromised by one thing—industrial safety. If you ever find yourself filming in a modern automotive plant, you’ll quickly tire of trying to shoot through metal grids and plastic shields as I did in my former career.
Perhaps most interesting, though, is the bending process used to produce the Cybertruck’s door panels. Moravy refers to the process as “airbending.” Typically, in the sheet steel bending world, that refers to a bending process where the sheet metal doesn’t fully bottom out in the tool, versus bottom bending, where it does. But the airbending process used on the Cybertruck panels actually involves a cushion of high speed air blown through the bottom press tool to float the metal panel. When bending a door panel, the bottom surface is left unmarred by the tool because it sits on this cushion of air. This surface then becomes the outer surface when assembled on the car. The upper press tool does contact the inner side of the outer door panel, but as this isn’t seen, the small amount of marring that does occur is not a problem.
We get to see one of the door production cells in action. A robotic arm with what appears to be a suction gripper picks up a stainless steel blank. It then places it in the air bending tool, with a Trumpf TruBend 5320 press performing the first bend in the part. The robot then rotates the work piece so the second bend can be performed. The part is measured by the bending machine during the process to ensure the bends are to the correct angle. The parts have a 5mm (~0.2 inch) internal bend radius according to Moravy. Once complete, the robot delivers the part to an output conveyor where it can be retrieved from the cell.
Notably, even though only the outer side of the door panel gets an air cushion, even the inside door panel surface looks great. Minimal marring is visible in the video, though it would be likely more apparent in real life. The door panels may be just millimeters thick, but that doesn’t mean they’re not tough. “It takes about 75% of the side crash loads, just through the panel itself,” Moravy explains. He notes the extra thickness versus the other Cybertruck panels provides desirable stiffness in this area.
The door panels themselves must be assembled, with the simple bent outer paired with the pressed inner. Naturally, this poses a challenge—how do you join the two without marking particularly the outside panel?
It’s actually a fairly straightforward process. The inner door panel first gets welded to a hinge reinforcement panel for added strength. The combined part is then laid atop an exterior door panel. A laser welding process runs around the perimeter of the inner panel, welding it to the back side of the exterior panel. It took a great deal of tweaking over many months to achieve this process without heat marks, distortions, or burn through being apparent on the outer surface of the Cybertruck’s doors.
There are some minor burn marks that are visible on the welds between the inner and outer door panels on the back side; where these are visible in the final product, a laser ablation step burns these off. The outer door panel also has two sound-deadening pads stuck inside to dampen noises and vibration. Final finishing of the door is achieved by a pair of robots with buffing pads that run over the complete door.
“As you can see, with all the equipment, we’re ready to roll at like, high volume,” says Moravy, while noting that the plant is currently not operating at full speed. He explains that quality is the first priority, with production running slowly until that task is mastered. One thing that’s also apparent in the video are the swathes of unused space on parts of the factory floor. For now, some of it is taken up with parked construction vehicles, but in time, it could prove useful space to add more manufacturing capacity.
We also get some side manufacturing lessons, too. Munro pays great credit to the supplier choices for tooling at the plant. It’s very much personal taste, of course, but engineers like Munro place great stock in the lessons learned from industrial experience. He quotes an old adage he lived by in his manufacturing days—”Don’t save me any money, I can’t afford it,” says Munro. It’s a sage piece of advice. While some brands of machinery may be more expensive, if they produce better parts, fewer defective parts, or cause fewer problems for engineers to solve, they probably save far more money in the long run. The initial cost of a machine is often quite small compared to the potential losses from downtime when a broken machine can’t make parts and holds up a whole plant.
Overall, it’s rare that an automaker welcomes in a video crew to show you exactly how they’re doing something. It’s even less common when it’s something brand new and interesting. Obviously, the Cybertruck and its stainless steel construction are fairly unique and novel, and it’s probably unlikely any other automakers will be rushing to replicate its work. In any case, though, it’s always interesting to learn about how cars are made, especially when they’re a bit weird like this one. It’ll be interesting to see how Tesla is able to crank up volume, and whether the company can keep the quality up.
Image credits: Munro Live via YouTube screenshots, Lewin Day (diagram)
“It takes about 75% of the side crash loads, just through the panel itself,”
Great, so now a Camry dent will total the truck because it has compromised the crash structure.
That statement also implies that it’s far stronger than a normal panel. It wouldn’t be capable of handling such loads if it weren’t significantly stronger.
It will be incredibly difficult to get a camry dent. 1.8mm is about 15 gauge stainless. That’s thicker than a commercial utility sink, and crazy hard.
Such brilliant stupidity! I find the engineering and production process fascinating even while being repulsed but the product spec and design. This also answers my question about the thickness of the panels, which were quoted earlier on as being 3mm, which I found the idea of to be bafflingly daft, but they settled on something more reasonable. With all the problem solving that had to be done with the engineering, process, tooling, etc., I’m actually impressed they brought this (almost?) to market as quickly as they have.
I’m curious where you take a vehicle like this for bodywork. How did DeLorean owners do it? One of my cars was recently scraped in parking lot and although bodywork has gotten eye-bleedingly expensive, any local shop can fix it.
Is Tesla getting into the bodywork business? Repair by replacement? Do they expect body shops to retool? Or for consumers to take a Star Wars “used universe” aesthetic view of their vehicles’ scrapes and blemishes?
Actually, that last one seems boldest and most environmentally friendly.
Considering the gigacastings underneath anything, above anything purely cosmetic damage its almost certainly going to be totalled.
DeLorean body panels were thin covers over composite. IIRC, the cars came with a SS brush for blending in light scratches. Don’t know what they did about damage. The panels could of course be repaired, but what that exactly entailed and the cost of it, how available are/were spares, IDK.
It looks like many repairs might be a bolt-off, bolt on affair since they’ve done away with the costly metal repair, prep, and paint. I’m sure panels are quite a bit more expensive than traditional constructed panels but it still might be a wash with those other costs eliminated.
On Wheeler Dealers when the flipped a DeLorean it needed some body work. The process was super interesting and required a guy that knew specifically how to do it.
If you’re just replacing panels, about any competent machine shop in the Midwest should be able to remake one in an afternoon. If the casting is damaged, well, hopefully your insurance covers a new vehicle.
Am I wrong or does it appear from the above story that the inner stamped panels are also stainless? If this is true then that’s better than I expected. I though only the outer polygon style panels would be stainless. Also, have crash safety ratings been released? A lot of freedom hating trolls seem to be jumping onto this idea that it will kill pedestrians and turn passengers into mush, amongst other ridiculous assumptions.
Inner and outer are both stainless. Inner is heated and stamped.
The guesses that it’ll be very dangerous to pedestrians in an accident isn’t exactly without basis. The shape alone makes it hard to imagine how it’ll have decent safety for pedestrians.
I think something that is extremely overlooked, partly to the fault of Tesla for not release exact numbers, is the strength and very specifically the hardness of HFS. The reason all cars get scratched and dented so easily is automotive paint is suuuuper soft, and the sheet metal it covers is very very thin, and much softer milder steel. HFS is allegedly a 300-series stainless, which is (generally) much harder as a material, meaning considerably harder to scratch. The reason the shopping cart demo seems to leave the truck unscratched is due to softer aluminum and plastic being unable to scratch the harder HFS.
If this seems unintuitive, that’s fair, it is. Look up demos/experiments online of people trying to break diamonds or other minerals. You can throw a diamond on a cast iron anvil and hit it as hard as you want, but the diamond will be completely unscathed and the anvil gouged. The same principal applies here. How will it perform in the real world, that I will reserve my judgement for, but in theory, it should be very robust relative to what we have.
I’m also interested in this, maybe there is some insight from Delorean owners about how scratchable their cars are? I’m assuming the stainless used in those is lesser quality than what Tesla is doing
Stop giving visibility to this dangerous POS.
Show us on the doll where the bad man touched you. Bro, you should seek help for your brainwashed hatred of the Cybertruck and Elon Musk. Some serious deprogramming is needed.
Love or hate it, the Cybertruck has to happen. Moon shots like this are how technology gets normalized. Plastic bumpers with styrofoam inserts?! That’s everyday technology now but imagine the conversation when they were being developed in the 80s.
That’s where we are today with Cybertruck. The only reason we’re paying more attention is that company is run by a narcissistic ADHD man-child billionaire.
Funny to compare an evolution of safety engineering for pedestrian, to this car that make the situation so luch worse than it already is for them.
Also you forgot nazi vilain between adhd and manchild.
It’d safer for pedestrian impact than a Ford F-150, the best selling truck. Are you protesting that as well?
Waiting for you to demonstrate that.
Waiting for you to demonstrate how the Cybertruck is more hazardous than the existing truck. Since you appear to be freaking out about this, I’m sure you have valid data at hand, right?
It start already with only hanging around the car, as camisa and others have stated, they’ve cut themselves on the panels. Not hard, except to stans, to imagine what it would do during an impact with a pedestrian.
So you have no data, nothing from production cars, and you have no idea why the Euro pedestrian safety standards actually raised the front of cars, not lowered them. It also appears that you’ve read no analysis of the newer pickups or seen any tests of forward pedestrian avoidance systems vs. Teslas stack. You have research to do.
Considering that the only data for the cybertruck that’s been released has been the head-on collision, I’d love to know how you came to that guestimate.
My point was not to compare safety tech, but rather to suggest that sometimes putting “ridiculous” stuff into production is the only way to innovate. But if you want a safety innovation comparison: most of us drive around with a small bomb about 2 feet from our faces. And yes, sometimes that tech goes wrong (ahem, Takata) but it’s generally accepted.
“Plastic bumpers with styrofoam inserts”
NO NO NO Urethane bumper covers over EPP(expanded polypropylene) bumper cores over bumper beams( function as replaceable crumple zone} over bumper mounts. EPS(expanded polystyrene, DOW chem. trademark Styrofoam) is a packaging and insulation material only, will dissolve if gas spills on it, and doesn’t recover from compression.
My serious concerns about how much force is required to deform the FHS edge on, in an accident scenario, is unchanged.
Is there any carbon steel in the Cyber Truck? So far, I know that the exterior panels are SST, inner doors are SST and giga castings are AL. What about the rest of the vehicle?
Asking for the rust belt.
With all due respect, is seems that manufacturers using carbon steel have done a decent job of rust prevention on modern car body panels. My 2003 Honda Element had zero body rust issues when I traded in after 12 years (yes, it had a lot of plastic outer panels). Even my 8 year old Ram Promaster is looking good after 8 years of western PA winters and only being washed a couple of times.
I bet there will be spin off aftermarket to paint the cyber truck.
Honestly, I’m impressed. The engineering seems outstanding. I share others’ concerns about long-term repair costs, but for every day scratches, dings, and stains I wonder if Cybertrucks will just develop a type of patina that we all come to regard as normal. After all, each of us drive cars that are painted and scratch and dent easily, so SS isn’t unique in its susceptibility to damage. And I often just live with dings and scrapes on my (old) cars because i’m not paying the thousands of dollars it would cost to fix them. So maybe our “ these trucks are gonna look terrible and get damaged so easily” fears are overblown
I wonder what’s gonna happen to the stainless finish when when a pigeon shits on a cybertruck, or it hits lovebugs.
Get out your Refrigerator Stainless cleaner and do the whole truck like others have to use wax LOL
I’m very surprised at the lack of plastic film for the outer panels. Yes, it costs more, but it greatly reduces the risk of damage during processing.
As for the environmental impact, I’m sure the could find a plastic that is completely recyclable and their handling of it could ensure keeping it clean.
As for the aluminum-bronze dies. Al-bronze is a common bearing material. It’s not a “soft” material. Neat choice.
Another thing: depending on the stainless steel alloy chosen, the laser cutting and welding can lead to rust forming (surface). No mention how they’re mitigating that risk.
Side note: in aerospace, we don’t usually call it stainless steel, we tend to call it CRES for Corrosion RESintant steel.
In the Isaacson book he mentions an anecdote about Elon trying to speed up the solar roof installation process to be done in a single day. He noticed that hours were wasted right up front just from removing the shingles from their cardboard and plastic and straps just to be thrown away. So he went back to the guys manufacturing the shingles and had them cut all that out because it was wasting time/money on both ends. So reading this bit my first assumption is they’re leaving the plastic film off for the same reasons.
This is complete nonsense. I have been assured by the internet commentariat that the Cybertruck is nothing more than a collection of fevered delusions by TwitterManBad.
No, bub, but I love you trying to stan here
The Tesla engineers are amazing. Creating not only the processes but the scale manufacturing for a vehicle this different is very impressive. You also have to give kudos to the management that told them, this is the job, make it happen, and then shoveled in buckets of money until they got it done.
Pretty neat, but they could have also just avoided needing to learn all these lessons and ultimately have sold the same amount of vehicles, if not more.
Sometimes engineers excel when given crazy goals. I am sure they learned things and developed processes that can be used in a more productive way. The Cybertruck is really just a very expensive research project.
Tesla’s job is to profitably manufacture EVs. It’s not to FAFO because of man-child delusions. You gotta put down the Kool-Aid. Not everything that a Musk company does is part of some meta game plan
By “put down the kool aid” do you mean automatically hate everything Tesla does because of who the CEO is? I hate Musk just as much as the next guy and have absolutely zero interest in owning a Cybertruck, but great engineering is great engineering. Horrible take 0/5 stars, do not recommend.
You can appreciate Tesla but still think that the CT is dumb. I don’t see any thing about automatically hating Tesla in my posts. You’re just (incorrectly) filling in the lines. I own Tesla stock, I like EVs, and I’d ultimately love to own one when I can spring for a new-to-me car purchase. There’s just a very real thing in the industry called “opportunity cost”, and I’m seeing Tesla blow money, effort, and time on a Falcon Door 2.0 when they still haven’t really delivered on the promises of 4680 and a good chunk of their model range is going to lose tax credit support. There’s nothing strategically valuable about how they approached CT, and I think it’s silly. Stop assuming everyone online is some sort of caricature of a hot take
Then what’s the problem? Do you disagree with the engineering methods they’ve created to make the truck?
The manufacturing engineering is truly fascinating on these, but your article confirms a couple of my beliefs.
Cybertrucks will always only be parked in the far abandoned corners of a lot and their alarm systems will be designed to alert if anyone or anything gets within 50 feet. Insurance companies will be totaling them after a pigeon or seagull bombing.
Actually the finish is quite robust. All the headlines about being bulletproof are pointless but that same quality basically makes them parking lot proof which is what they should be advertising. In the video below they ram a shopping cart loaded down with a stuntman into the door multiple times with no damage.
See exhibit A: https://youtu.be/adZztW0YbJ0?si=CwIZlg1-yDP6EJe_&t=1350
Buddy, everything looks better on video. And they didn’t show close up. The fingerprints all over and well visible from far are disgusting tho.
I’m expecting CT owners will deal with fingerprints on their trucks the same way I do on my fridge, lots of magnets.
Unfortunately, being a high grade stainless, its not likely that magnets will stick.
Your fridge is probably made of 304 or 430, which is semi-magnetic.
Well there go all my plans for sticking cheap refrigerator magnets on the back of cybertrucks in the Costco parking lot. Unless, I bring some superglue…
If I had a Cybertruck, I would park it in the tightest spots possible. I expect the sentry mode footage to be filled with people trying to dent it. The tighter the spot, the less room they have to wind up their hits.
Curious, wouldn’t heating before stamping cause color changes to stainless? I could see uniform heating make the colors look the same, but wouldn’t that also require uniform cooling too? Either way, it looks very impressive to me.
Color change tends to be a function of max temperature more than cooling speed. It’s caused by oxide formation, and that is largely temp dependent.
It’s so neat to see this kind of detail exposed. One of my first jobs was inspecting laser welded and panel bent stainless. That stuff is nightmarish to try and keep from scratching, not to mention oil stains and grain variations. But if they can get their process dialed in from a quality standpoint, these should be cheap to build. Their “airbend” solution is really cool.
It’s interesting to see this kind of manufacturing tech used to build a car at scale. Funny to think the fridge fab shop could be spitting out cybertruck parts (I have less than pleasant things to say about trumpf machines).
Thanks for your experienced take.
I didn’t think Tesla could pull off manufacturing these at scale, but it appears I was wrong. I think the design is hideous, but I appreciate the materials science and manufacturing engineering behind this vehicle. If your cheap to build comment is correct, then perhaps we’ll see more stainless vehicles in the future.
Looking forward to seeing the crash test results.
Injecting air into the bottom die is a really clever way to make a boundary layer and limit panel damage. The method I’m most familiar with is using disposable silicone sheets which essentially add a bit of compressibility to the part face.
I am interested in the crash test results too. Looking at the casting, I think it will be fine for occupants, but man those sheet panels give me pause. They look like shrapnel waiting to happen
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