Tesla Gigacast - Pros and Cons

Tesla announced an advancement in its manufacturing process that further cuts costs by extending its existing “gigacast” capability to stamping out nearly the entire underframe of the car as a single part. Already, Tesla uses giant presses – bigger than any used by other auto makers – to create the bottom of the chassis in two large pieces. They are now adopting a process that will combine the front and back halves for some of their models, further reducing assembly time.

This sounds GREAT… for lowering original manufacturing costs. However, I wonder what insurance companies are going to conclude in a year or two after these new monolith chassis models hit the streets and start hitting other vehicles in accidents. Higher parts counts lead to higher manufacturing / assembly costs but can help REDUCE the count of parts requiring replacement after a collision. If the entire underbody of the car is one part during manufacturing, there may be no way for Tesla to sell “quarters” or even “halves” of underbodies to body shops to use in cases where maybe just a driver’s side rear was hit, affecting one corner of the car. And even if that was possible, it might be impossible to weld them together and recreate the original strength of the all-in-one stamped underbody.

A quick Google search seems to yield the factoid that the average PERSON is involved in an auto accident every 17 years or so. I would imagine those results are skewed towards those younger in age. The average age of a car on US roads is about 12.5 years. There’s no way to extrapolate those two factoids into a third statistic – the average age of a car when involved in an accident.

If the average age of a Tesla built with this one-piece underbody would be 12-15 years when involved in an accident, it probably won’t matter because the car would have been likely totalled by the insurance company anyway. If one of these new vehicles is hit when only maybe three to seven years old, the extra labor to swap out essentially the entire undercarriage might accelerate write-offs of these vehicles, sticking customers with a bill to cover the cost themselves or buy another new car before they can really afford it. At a minimum, it seems likely insurance rates on these cars would spike significantly unless Telsa makes it VERY easy to separate the “sled” from the rest of the car outside the factory. At worst, this new production strategy may reduce up-front manufacturing costs but make the cars disposable after nearly any hit, completely negating any ecological benefit.

WTH

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Once the energy credits are sold, Tesla doesn’t care. If the car has to be replaced, the issue will be what alternatives exist other than Tesla. That would be about the late 2020s (given an accident every 4-7 yrs that totals a car) , so it is likely there will be a far wider range of alternative vehicles.

In 2017 I had a minor fender bender in my Honda Civic. The car was totaled. Cars are made to fall apart. The insurers licked their chops. It was an excuse to jack my rates way up.

I turned to USAA and got a better-than-fair deal. I slipped through Geico’s hands, Amica’s and the rest. Not everyone is so lucky.

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A surprisingly low amount of damage will cause an insurance company to total a vehicle. I’d be suprised if this is a problem unique to Tesla.

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The insurers save money totaling cars. The old ramrods used to kill or maim people. New cars falling apart save lives. The math is done by the actuaries long before the car rolls off the assembly line. The totaled cars still have to be paid for by the insured vehicle owner, and the rates skyrocket.

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You can’t correlate the average age of the vehicle and the average length between auto accidents. You would need to look at the average age of vehicles involved in collisions and ignore the time between each accident.

It is exceptionally difficult to find this data and every search result wants to default to data on the age of the driver and not the age of the car.

What data I could find was sketchy at best.

To identify the 10 most accident-prone car models, the Insurify data science team turned to its database of more than 4.6 million car insurance applications. While several sports cars predictably made the list, some of the top models are surprising.

the $51,900 Audi S4 topped the list of accident-prone cars. Notably, Audi S4 drivers also rack up more speeding tickets than the average driver, with 14.6% reporting a speeding violation on record in 2023.


Note, age of vehicle is still not tracked but it is a fair assumption that the vast majority of those Audi A4s were less than 10 years old, and certainly less than 17 years old.

One might want to look at CA stats (I tried and could not find it) and see how they rank their vehicles by most crashed/wrecked/involved in accidents. The higher rate of Tesla sales in CA would paint a clearer picture than national stats that are going to be dominated by more traditional automakers.

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The article is not talking about the A4, it is talking about the S4, a high performance variant. Most of the models cited in the article are either high performance models, or cheap models more often driven by younger/risk-taking drivers.

I will also note the article is using a “gee whiz” graph to make the listed models look far more crash prone than the accident incidence percentage actually says they are. The difference between the S4, and the average, is only about 4 percentage points, but the “gee whiz” graph makes the S4 appear 7 or 8 times more likely to crash than the “average”.

Steve

I don’t see the point you are trying to illustrate in your correction. Whether they are A4 or S4, young or old drivers, nothing suggests that they are an average of 17 year old VEHICLES.

I don’t think you grasp the content of my post. The OP had a query as to the length of time between accidents for individuals (17 yrs) and the age of vehicles. This is not about the age of the driver. The point of my reply was to suggest that the vehicle (S4 in this case) is not likely to be a vehicle that has been on the road for an average of 17 years and by extension, the average age for Teslas in accidents will also probably be less than 12-15 years old.

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I was addressing the content of the link, percentage of a model in an accident, and A4 being conflated with the S4. For that matter, even a car that is expensive new, like an A4, can be driven by a young person, if age has devalued it enough to be “affordable”.

I guess you are right, I don’t understand what your point was, or how that article informed that point.

Steve

Tesla is also in the insurance business. Repair is a very big consideration in their calculations. So far they have not seriously repriced their insurance despite many cars in the insured fleet having large castings at this point.

Their claim is that most minor repairs can be done by patching / welding. Anything nasty enough to have caused serious structural damage to the cast underbody would have totaled any car, so it doesn’t matter.

But I have to admit I haven’t looked into the subject deeply. The world is just too full of people with “concerns” that effectively start with “let’s assume that Tesla engineers are stupid”. It just ain’t so.

-IGU-

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Castings are actually quite easy to repair as long as they have excellent reference points to ensure the repair does not warp the fixture such that fasteners which can be 10’ or more apart are out of tolerance.

Repair jigs and procedures and qualifications will be provided if Tesla is serious about repairing them.

Quite honestly, I doubt they care enough about the process to override savings in assembly operations.

The casting design is about assembly labor, mistake reduction and takt time. Service and repairs after an accident are secondary considerations.

Look up Aluminum Casting repair. It’s like black magic to the general public, but is quite simple to do. Any shop that does aluminum welding for marine or industrial products will have a bench full of welders and helpers who could do this stuff in their sleep.

It’s not that big of a leap to see them cross the street into a Tesla Collision repair business.

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I can’t grasp it either.

:rofl: :rofl: :rofl:

I don’t understand why it is called a press if all this is is a casting? To me a press implies forging. A casting is simply a mold that one pours molten metal into. And is there anything special about a casting that is large in the first place?

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“Press” refers to the pressure the machine exerts to make the casting. 9,000 ton giga press

The Captain

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I don’t know enough about casting. Did not realize it involved pressure. I thought it was just pouring into a mold.

Traditional castings don’t need pressure, just pour in the liquid and let it set. The Giga press has to fill a huge mold with hot aluminum in under a second so that it cools with no stress problems.

Shots of molten aluminium weighing 80 kilograms (180 lb) are injected into the cold-chamber casting mold with a velocity of 10 metres per second (22 mph; 36 km/h).[6] The cycle time is ~80‒90 seconds,[2] allowing an initial output rate of 40‒45 completed castings per hour, or ~1,000 castings per day.

The Captain

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Different types of castings. Rings are made using investment casting (to minimize use of expensive gold/silver).

As stated, most low-volume castings are sand castings–use a pattern (usually made of mahogany) to make impression in sand, pour in liquid gray iron, let it sit a bit, then take out the part and let it cool. Tolerances are not that important because the reason to use a sand casting is it is “good enough” as a material and it is relatively easy to machine to reasonable specifications. Gray iron castings can last 40-50-75+ years given no unusual stressors on the material. For a short while, the business where I worked had a WWI engine lathe that had been rebuilt. The serial number on the end of the machine had been partially obliterated before we got it, so everyone thought it was a WWII “special built” machine. I closely examined the S/N tag one day and noted only one end of the number was crushed (so unreadable). Called mfr and asked about age/type of machine with an added digit and was immediately told it was a WWI (or older) engine lathe, and no parts (or other info) available, etc. Owner then swapped it for work at one of our suppliers. Having a machine shop in-house was not worth it unless you are able to keep the people AND the machines busy most of the time.

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I spent a summer working in a malleable iron foundry. Mass production, sand casting, metal patterns. Diff carriers, gear cases, u-joint yokes, brake calipers, a “bomb plug”, and railroad “bearing adapters”.

Steve

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Tesla already does collision repair. I’ve (unfortunately) been their customer twice. Both times they did a great job.

https://www.tesla.com/findus/list/bodyshops/United%20States

-IGU-

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Tesla’s new manufacturing process, which combines the entire underframe of the car into a single part, could potentially lead to challenges for insurance companies and repairability after accidents. Repair costs may increase, and the cars could be more prone to being declared totaled by insurers. This might impact insurance rates and the overall ecological benefit of the manufacturing process.

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