Tesla’s new car-building process could be an industrial breakthrough | Hacker News Reader

Tesla’s new car-building process could be an industrial breakthrough

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34 pointsrntn32 comments

The repairability / ability to replace these giant castings doesn't seem to come up in these articles. Are the cars just going to be disposable if minor damage occurs?

Insurance companies are already writing off damaged Teslas because of repairability issues and this would seem to make the problem worse.

New car price may go down, but insurance may skyrocket, so not necessarily an overall win.

What type of minor damage would require replacing the castings?

Any impact that damages any part of the massive cast unibody. Compared to stamped metal, a cast metal part is brittle under impact and is far more likely to crack rather than deforming. That can be good for safety ratings - in a collision the cast metal will crack, absorbing and dispersing the impact. However, when most of the car's structure is a single piece of cast metal there is no viable way to replace just the cracked piece.

Yes, you can cut and weld it, in theory. But aluminum is difficult to weld and cast metals are extremely difficult to weld. Repairing cast aluminum is a highly specialized skill that is unusual even among professional metalworkers.

Unibody cars are already totaled out for frame damage pretty often. It can be very hard to properly repair structural and safety elements of a modern unibody. Not to say you won't see it on the road, but it will be a salvage/reconstructed title that won't carrying comprehensive insurance ever again.

Yea, I can't imagine getting all the safety systems working again in a modern car after a crash.

In older cars it was easy to chop them in two and weld them together however you wanted. But these days with the concepts where the engine compartment and trunk are crush zones and the passenger compartment is rigid so they occupants don't get crushed, there is a ton of non visible damage in even minor impacts.

In order to get a salvage title the car needs to be totaled.

Insurance doesn’t care if there is frame damage. It only cares how much the car is worth, how much it’s going to cost to fix and how much it’s worth at an auction in its current state. They run the numbers and decide if they are fixing or totaling the car.

There is a reason tesla is expensive to insure.

It's also liability. If insurance determines frame damage, they're inclined to often total it and settle with you. You ain't getting that car unless you buy it back. I know this since I've worked in insurance, they don't want to be liable if the car doesn't perform to manufacturers specifications while driving or another accident. Initial repair/value cost is a determining factor yes, but doubly so future liability. Take it to their preferred shop, repair is inadequate, fails to perform while driving = they're liable for way more than initially.

But that's not minor damage, it's the sort of damage that will bend the frame on a normal vehicle. While it's possible to repair a car with a bent frame, they're typically written off. And if they are repaired, they're rarely the same car as they were before the accident.

n=1 but I’ve been in collisions with unibody cars, and they were not written off just because the frame was bent. They were repaired.

Granted, these were fender benders. Not serious collisions.

Then one would assume that the cast components would not have been broken either.

The crumple zones in modern cars hide a lot of serious damage in a minor appearing accident. My sister in law was hit a few months ago and I was able to drive the car home with what just appeared to be a missing tail light and had to tie down the trunk.

When the auto shop looked at it they could see serious warping and bends at welds all over places in the unibody that would cost more to repair than the car is worth.

> n=1 but I’ve been in collisions with unibody cars, and they were not written off just because the frame was bent.

You might've missed this earlier comment by @unregistereddev: "Compared to stamped metal, a cast metal part is brittle under impact and is far more likely to crack rather than deforming."

In Tesla's case specifically, this isn't just hypothetical: https://www.thedrive.com/news/tesla-model-y-owner-finds-scar...

Not necessarily. The unibody "frame" is a much smaller piece than what Tesla has combined into a single component. For example, dropping and replacing a bent subframe (the part that typically holds the front suspension) will cost 2-3 thousand dollars on a normal vehicle - but damaging the same component in this Tesla design requires replacing the whole "gigacasting".

People weld cast metal parts all the time. Same for aluminum. The process is just less familiar... aluminum wire is softer than steel so you can't just load it into the MIG and go - you usually want a wire feed gun that puts the spool directly on the back of the MIG gun. And you would usually use Argon shield gas (rather than C25 or C100 for stuff like mild steel).

Tesla's gigacasting cars are roughly as repairable as any other modern car. Lower speed collisions can sometimes be repaired. The repair may not leave it as structurally sound or with the same collision resistance. The older the car gets the more likely it is to be totaled even in such a lower speed collision because these kinds of repairs are labor intensive.

Medium and high speed collisions are always a full loss event. That's a deliberate design decision to sacrifice the car (eg crumple zones) to protect the passengers.

Insurance totaling out Teslas is to some degree an early adopter problem. Parts are less available, service centers with experience may not exist in your area, third party service manuals haven't been published, etc. These things make the cars more expensive to repair. All of these issues are rapidly improving but it should be obvious that they aren't a 100 year old car maker so their network of spare parts and repair shops will smart out smaller.

Everyday usage, apparently.

https://www.reddit.com/r/RealTesla/comments/1618vya/austinma...

It’ll probably end up similar to Lotus damage, almost an instant write-off.

Sure, but that's not Tesla's problem, just another hidden cost passed off to the consumer. Car insurance costs are skyrocketing, and people really should call to see how much a new vehicle is going to cost to insure first, but how many people really do that? From what I remember, I pay about 6x more than I did 20 years ago, but that's also because new cars are more expensive (inflation). I don't see cars getting significantly cheaper any time soon. New cars in China are competitive in price and features with any other new car but not like 10x cheaper. Despite the occasional "sale price", if Tesla can make a cheaper car they will also keep the profits.

But still, inflation is at 4% and car insurance went up +19% this year. [1] I'm sure it will keep raising every year until they find some nice equilibrium where... people don't want to buy cars? That doesn't seem very likely, what with all the amazing public transportation options we have in this country. However, insurance companies generally pay out more than they take in premiums. They invest the premiums to make their profits. So it's not entirely price gouging. Operating a vehicle IS becoming more expensive for a bunch of these reasons. But for a lot of people, it's also not an option. The top 3 reasons in that article are: worse drivers, more expensive repairs and (sad trombone) natural disasters.

Kind of a... situation our society has backed itself into over the last 100 years in promoting private car ownership over shared infrastructure. Who could have seen this coming? /s

[1] https://www.npr.org/2023/09/13/1199032000/car-auto-insurance...

Tesla sells insurance on their cars in many jurisdictions, so they are directly motivated to make their cars cheaper to repair.

Depends what the small letters say. Not all insurances are equal, unfortunately.

Very good point. But... I'm sure it's profitable for them no matter how expensive the car is to repair. I don't think that's a driver to make the car cheaper to repair. In fact, if they are harder to repair it's probably even better! The "write off" part of the typical insurance claim is different because they're paying themselves in that case.

The insurance coverage model provides extra cash now. The market value of a Tesla is different than the raw material value (batteries, raw materials, recycling) so I'm sure Tesla doesn't care about that because it's not generic insurance for any car, it's Tesla insurance for Teslas. They can charge less, get extra cash flow, and the raw material goes right back into the factory to make a brand new one.

In mild to moderate impacts, crash energy is absorbed not by the cast (or stamped) frame, but by replaceable components external to the frame itself.

For minor impacts, that's the bumper, energy absorbing foam, and/or impact absorbing pistons that sit behind the bumper or crash bar.

For moderate impacts, it's deformable crush cans that bolt onto the vehicle's frame (whether cast, stamped, extruded or hydroformed)

I suspect that a crash serious enough to damage the unibody would be a write-off with or without it.

In modern cars, mere deployment of airbags is stupidly expensive, and almost a write-off on its own. You need to replace not just the airbags and seatbelts, but also seats and all interior parts that they've exploded (and airbags are everywhere now).

Worth noting that all of the "sources" this article, and the Reuters piece it is based on, appear to be Tesla executives or staff.

I guess we’re back to unquestioning stenography of Tesla “breakthroughs”. My cat “could” also be an industrial breakthrough, though it is highly unlikely because he is old and lazy.

They [don't have a PR department](https://electrek.co/2020/10/06/tesla-dissolves-pr-department...) so the press can't even ask them for comment

Of course it has to be Tesla’s source. It’s a new process that hasn’t been made public. Who else it could be? And why are the quotes around source? Reuter apparently found it newsworthy to publish the news.

Is it any different than countless of Apple’s rumors, such as this?

Apple Makes Major Progress on No-Prick Blood Glucose Tracking for Its Watch

https://news.ycombinator.com/item?id=34899471

One owner already found a crack in their cast: https://www.thedrive.com/news/tesla-model-y-owner-finds-scar....

Relatedly, I'll pass on owning a car designed by someone who is mentally unstable.

This is crazy. Castings aren't repairable. Disposable cars aren't environmentally friendly.

The key word here is ‘could’. Not will, could.

I think the giant casting could improve repairability, if they can be cheaply manufactured.

You can buy the entire section and it gets welded at the same place as the original. Then just swap the working parts across.

It can dramatically lower the labour costs.

> Tesla’s new car-building process could be an industrial breakthrough

Tesla is not a car. It is a toy. It lacks basic car interface (odometer).

It produces cars that are within spec:

https://www.autoevolution.com/news/new-images-and-video-conf...

love seeing this type (manufacturing process) innovations!

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