[HN Gopher] Gigapresses - the die casts reshaping car manufacturing
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Gigapresses - the die casts reshaping car manufacturing
Author : lxm
Score : 79 points
Date : 2023-02-14 18:50 UTC (1 days ago)
(HTM) web link (www.reuters.com)
(TXT) w3m dump (www.reuters.com)
| cs702 wrote:
| So far, only Tesla is using giga-presses to reduce the number of
| parts that must be welded together in each vehicle and lower
| costs. Other car manufacturers have barely started exploring the
| possible use of these giga-presses, and seem reluctant to
| transition away from time-tested approaches to manufacturing.
| Quoting from the OP:
|
| _> After initially considering die casting for its upcoming
| Trinity model, Volkswagen (VOWG_p.DE) has backtracked, while BMW
| (BMWG.DE) has never expressed an interest. Ferrario said the auto
| industry tended to be conservative and that no one liked upending
| established processes, but he rejected idea that die casting
| posed a risk to jobs at carmakers, noting body-making was already
| highly automated._
|
| Thanks in part to its use of these giga-presses, Tesla currently
| has the highest profit margins of any mainstream car company.
| It's not a coincidence.
| digdugdirk wrote:
| Yes and no. Automakers reluctance to new design methodologies
| is coming from a place of safety - the "traditional"
| engineering mindset. In civil and mechanical engineering, it
| takes a long time to be fully confident that you've found all
| the edge cases that might cause catastrophic failure - and
| catastrophic failure in certain industries (Automotive industry
| included) generally means death.
|
| Tesla is coming from a "software" engineering mindset. Move
| fast, break things, etc, etc. This is far easier when dealing
| with bits and with code. The likelihood of death and
| dismemberment is also far lower if you make mistakes.
| senttoschool wrote:
| Is it the gigapress that allows Tesla to have high margins?
|
| Could it also be that EV cars are subsidized around the world
| by governments? Maybe Tesla's "self driving beta" addon adds to
| the profit more?
|
| I genuinely don't know.
| cs702 wrote:
| It's one of the reasons, but not the only one.
|
| That's why I wrote "Thanks _in part_ to... "
| kjksf wrote:
| All EVs are subsidized and pretty much all of them (except
| Tesla) are loosing money while Tesla has industry leading
| gross and operating profit margins.
|
| So it's definitely not subsidies.
|
| On a definitional level, gross profit is difference between
| price and cost.
|
| Tesla has biggest difference which implies that it's a
| combination of charging higher prices and having lower
| production cost that other.
| akiselev wrote:
| Only EVs assembled in the US can receive the full subsidy
| now, ever since the Inflation Reduction Act came into
| force.
| [deleted]
| sliken wrote:
| Telsa has been relentless in simplifying the part count of a
| tesla. Each part needs to designed, tracked, inventoried,
| installed, verified, made available for repairs, increases
| the size of the factory, and decreases the rate of
| production. Added parts also require space to install,
| clearance, sometimes custom tools, testing, might create
| vibration/wear/noise that requires mitigation, etc.
|
| The front and rear chassis used to require 100s of robots and
| parts, and then alignment would have to be checked, more
| material used, more time, more robots, etc. Replacing the
| front and rear chassis removed 300 robots ... each, and of
| course the factory space for the robots, and the time for the
| assembly line to run past those robots.
|
| The glass roof, which IMO isn't a big feature, can be
| installed after the chassis is built. Enabling robots to
| install the dashboard, central console, seats, etc before the
| roof is installed.
|
| On most cars the dashboard is complex, multilayered, complex
| set of sensors, displays, spinning needles (speed, rpm, temp,
| fuel levels, etc). On a Tesla the dash is built on a big
| square straight piece of aluminum, a simple slot for airflow
| (no fancy/fiddly air flow controls), and a 15" display.
| Likely reducing 100s of parts.
|
| The octovalve and related cooling system is a marvel as well,
| nicely integrating heating/cooling of the cabin, motors, and
| battery. Dramatically simpler than competing solutions, in
| particular the Ford Mach E and Lightning.
|
| Most cars have an extremely complex set of CPUs, sensors, and
| control distributed all around the car. Chips in doors for
| locks/windows, a separate system for ABS (usually from
| bosche), networks of temperature/pressure/movement sensors,
| torque controls/monitoring for window motors, windshield
| wipers, airflow motors, etc. In the model 3 it's largely
| integrated into a single board at a level of integration
| Munroe claims they have seen in no other car, or even any
| product ... outside of a satellite.
|
| This might sound like hand waving and marketing, but one
| metric that supports this is the cars products per square
| foot of factory per hour. Tesla is way ahead. It's also
| supported by high profit margins, even when compared to
| companies that have as high or higher prices.
|
| So yes I'd say that the gigapress is a key part of reducing
| the part count, assembly time, and number of robots required
| to build a car. The result is a Tesla factory builds more
| cars than the competitions factory of the same size.
| lallysingh wrote:
| The underlying trick to this, in part, is the fact that
| Tesla's making exactly 4 models (S3XY). The models are
| long-lived. This lets them invest in specialized parts that
| reduce the cost (significantly!) of their vehicle. I read a
| stat somewhere that the Y takes 10 hours to build.
|
| Disclaimer: I respect Tesla's manufacturing prowess, I
| despise the self driving claims, and think the vehicles are
| hideous.
| sliken wrote:
| Indeed. Much like Apple. Apple has 4 ish laptops, that
| generally don't change much year to year. Compared to
| Dell or HP who have MANY more models, often seems like 4
| models or so per market (edu, business, consumer, gaming,
| etc.) and are refreshed often.
|
| Agreed on the self driving. Not a big fan of the Tesla
| look, but after living with one I'm a fan. Then again
| I've had some ugly cars, early Acura GSR (with the tiny
| headlights), early Subaru WRX, and early Forester Turbo.
| None would win any beauty contests. Model 3 generally
| seems like the look is determined by a wind tunnel. At
| least the model S (at least in some trims) is pleasantly
| curvy and has some style.
| KaiserPro wrote:
| Thats just standard manufacturing
|
| > Most cars have an extremely complex set of CPUs, sensors,
| and control distributed all around the car. Chips in doors
| for locks/windows, a separate system for ABS (usually from
| bosche), networks of temperature/pressure/movement sensors,
| torque controls/monitoring for window motors, windshield
| wipers, airflow motors, etc. In the model 3 it's largely
| integrated into a single board
|
| yeahnah, thats deffo not true.
|
| tesla has a similar number of sensors, actuators and other
| junk. It even has an ABS pump too. How do they think they
| measure torque if there aren't any torque sensors?
|
| Having everything wired directly to a single board makes
| the wireloom really really unwieldy. Telsa use the same
| automotive busses everyone else does. (it probably uses ALL
| THE BUSSES, because why not.)
|
| the reason the reason tesla make a profit is that they've
| been value engineering the same three cars for close to ten
| years. however, they have only been making a profit since
| 2020.
|
| The other key is producing a car to a standard of something
| retailing for less than half the price. The top end Kia EV
| 4 feels much more "posh" than a model y, which is much more
| expensive. The killer feature of the EV 4 is that its
| waterproof.
| sacred_numbers wrote:
| I think the biggest reason for Tesla's gross margins is that
| millions of people want EVs for various reasons (gas prices,
| environmental concerns, fun, status) and Tesla is one of the
| only companies making them in large quantities. They don't
| have to be the best (even though they probably are on many
| metrics). They just have to be available and they can kind of
| set their price.
| rootusrootus wrote:
| I think it's vertical integration in general that drives
| their profit margin. It's why Teslas are good but not great,
| and will rarely be the best at any particular thing. Brewing
| up your own rain-sensing wipers saves on component costs, but
| is inferior. Building your own seats saves on costs, but is
| inferior. They're playing for the middle. Not a bad strategy
| at all if you're going for profits, so it makes sense.
|
| It'll be interesting to see how it all settles out compared
| to the legacy manufacturing style of subbing out components.
| Some people will pay extra for Recaros (me!) but a lot of
| people couldn't care less.
| martin8412 wrote:
| They're suspected of underallocating funds for warranty
| repairs. Those funds would normally eat into the profit
| margin, but at Tesla they're supposedly accounted as good
| will service, so it comes out of a different post.
| sliken wrote:
| Never seen a Tesla review claiming the seats were inferior.
| In a few they were claimed they claimed they were among the
| best, but most reviews don't mention the seats in
| particular.
| tyfon wrote:
| The seats in my X and 3 are the only car seats I've tried
| that does not give me back pain after long trips.
|
| They are one of the biggest reasons i drive tesla instead
| of the etron.
| toomuchtodo wrote:
| https://english.hani.co.kr/arti/english_edition/e_business/1.
| ..
|
| > The secret behind Tesla's 30% gross margin
|
| > The company's Q3 sales rose 58% year-on-year despite a 6%
| decrease in average selling price, allowing for high margins
| for the electric vehicle manufacturer
|
| > Analysts point to another factor behind Tesla's high profit
| margin. Park Hyung-keun, a senior researcher at POSCO
| Research Institute, said, "Through vertical integration by
| directly being involved from floor design to parts supply and
| demand, production and service, Tesla has helped reduce costs
| by raising the degree of its parts integration and cutting
| overlapping costs."
|
| > Tesla's unique structure of vertical integration, ranging
| from the development of semiconductor chips, software and
| batteries for electric vehicles, to charging, unmanned
| driving and insurance services, helps lower costs. Its "do-
| it-all" approach simplifies the automotive production process
| in a manner resembling that of electronic products. In
| contrast, other automakers actively utilize production
| outsourcing to diversify vehicle quality risks and raise
| output efficiency.
|
| > A leading example is Tesla's "giga" aluminum die-casting
| process. A Giga Press weighing more than 1 giga pound (400
| tonnes, or around 900,000 pounds) stamps the entire rear
| chassis of a car with a large aluminum alloy. About 70 metal
| plates can be welded to the chassis, but giga casting can
| simplify the process and slash production costs by about 40%.
| This is why Tesla electric vehicles have recently reduced
| panel gaps issues -- defects caused by misaligned steel plate
| seams.
| hef19898 wrote:
| So instead of figuring out "precision" welding (maybe
| SpaceX could have helped out?), Musk used pounds instead of
| kg or tons in order to implement "Giga"presses? Well, at
| least the manufacturing inexperienced Tesla crowd has
| something new to rave about... Still no < 35k Model 3 so.
| fragmede wrote:
| Why would, or should a business decide to make _less_
| money selling a cheaper version of a product when demand
| for the more expense (and hence more profitable) product
| shows no sign of waning? Don 't get me wrong, I'd love to
| buy a $35,000 Model 3, but it makes no business sense,
| especially considering the fact that the average new car
| cost is something like $44k these days.
| zaroth wrote:
| Just food for thought... $35k in Feb 2019 when Tesla
| announced the "$35k Model 3" is now just under $42k
| simply adjusted for inflation.
| toomuchtodo wrote:
| They found a cheaper, faster, more efficient way to make
| structural components. SpaceX already shared with Tesla
| how to friction stir weld [1] (and that technique is
| still used currently [2]), but that is not as fast as
| stamping out body components. Simplicity is the ultimate
| sophistication. There is no extra credit for making your
| manufacturing process more complex than necessary (if you
| want to show off, fire your EV into space). Tesla's
| manufacturing ramp rate is primarily a function of how
| fast the org can improve the speed and process at which
| atoms travel through the manufacturing process, feedstock
| to final product.
|
| [1] https://electrek.co/2015/05/24/spacex-transferred-
| novel-weld...
|
| [2] https://www.teslarati.com/tesla-model-y-spacex-
| welding-techn...
| hef19898 wrote:
| Tesla tried full automation, which didn't work. Now they
| use pressed parts limiting the use of platform
| startegies, which enable all other manufacturers to
| produce a multitude of models, including loe cost ones,
| using the same tooling, parts and R&D. I guess we will
| see were that ends.
| jackmott42 wrote:
| Everything is subsidized.
| ajross wrote:
| _All_ auto manufacturers are subsidized in some sense.
| Remember that GM was straight up insolvent in 2009 and had to
| be bailed out with enormous federally-guaranteed loans.
|
| But none of that discounts the value of talking about
| engineering activities involved in reducing the _costs_ of
| production, because that stuff matters too. And yes, single-
| piece chassis are absolutely part of that, as is the
| minimalist interior (the cockpit BOM for a Tesla is a tiny
| fraction of what you see on competing EVs), the ongoing
| sensor fusion architecture (yes, everyone loves to scream
| about it here, but the upshot is that Tesla doesn 't pay for
| the radar units everyone else uses), etc...
|
| They're actually extremely trim vehicles from an assembly
| perspective. There's a Munroe video out somewhere where he
| estimates production costs for a Y vs. a Mach-E and figures
| there's something like a $10k advantage for Tesla.
| KaiserPro wrote:
| > Other car manufacturers have barely started exploring the
| possible use of these giga-presses
|
| Lets be clear here, tesla are doing this for the rear subframe:
| https://electrek.co/2021/01/11/tesla-starts-production-model...
|
| And they want to scale it up, from what I see to the whole
| bottom of the car. This seems like a big reaction from how they
| used to do things with a billion different fasteners.
|
| Now, I think why the other companies don't immediately jump on
| this is that making a die that big is really expensive, and I
| imagine high maintenance. Tesla will probably get away with it
| because they don't really care all that much about tolerance,
| so will run the die a lot longer than a safe manufacturer.
|
| Also, tesla don't actually make that many models so they only
| need a limited number of presses and dies to be effective.
| stetrain wrote:
| They also do the front subframe for the Model Y at some
| factories.
|
| https://www.notateslaapp.com/news/1037/a-peek-at-tesla-s-
| sin...
| jgalt212 wrote:
| > Battery packs currently make up 25%-40% of the total cost of
| BEVs.
|
| > Automakers using aluminium casting machines claim they can
| reduce investments needed to build chassis - a vehicle's second
| most expensive component after the engine - by 40%, and the
| average cost of their parts by 30%, Ferrario said.
|
| I'm having trouble with the math.
|
| 40% battery
|
| 41% chassis
|
| 42% engine
|
| 123% !
|
| or
|
| 25% battery
|
| 26% chassis
|
| 27% engine
|
| 78% total (rest of car ~ 22%)
| flavius29663 wrote:
| > reduce investments needed to build chassis - a vehicle's
| second most expensive component after the engine - by 40%, and
|
| To me this is pretty clear: the press reduces the cost of the
| chassis by 40%. It could be 10%, 80% of the total cost of the
| car, it doesn't say.
| redundantly wrote:
| > I'm having trouble with the math.
|
| The trouble you're having is taking it literally. These are
| averages, not absolutes.
| notJim wrote:
| > 123% !
|
| Now you understand why EVs cost so much more than ICE vehicles!
| lallysingh wrote:
| Battery: 40%. Leaves the remainder: 60%. Chassis is the most
| expensive component of that remainder (no engine in EVs). Let's
| pretend the battery and chassis are the only two parts:
|
| 40% + ((1-40%)*60%) = 40%+36% = 76% cost of original. 24%
| reduction.
| mvidal01 wrote:
| This youtube video seems related.
|
| https://www.youtube.com/watch?v=hpgK51w6uhk
|
| This is the story of America's massive forging presses built
| during the cold war used to build America's most advanced
| machinery - the Heavy Press Program. Modern airplanes, missiles,
| helicopters, turbines - all have parts made on these giant
| machines!
|
| The Machine Thinking channel seems interesting.
| baybal2 wrote:
| [dead]
| jameshart wrote:
| I am not an expert so I am confused by terminology here.
|
| These machines are referred to as 'presses', but the technique is
| referred to as 'die casting'.
|
| my naive understanding is that pressing to form things would be
| more a form of 'forging' than 'casting'. Doesn't casting refer to
| molding things from molten metal?
|
| Is the distinction that die casting done at higher pressure than
| some other form of casting, to produce results more akin to
| injection molding, and therefore requires 'presses' to hold the
| tool dies in place?
|
| Or am I misunderstanding words completely?
| tristor wrote:
| The difference between casting and die casting, is that casting
| is done with a sacrificial mold at lower pressures, die casting
| is done at high pressure using a tool die that is reused
| multiple times. Die casting is essentially stamping out a part
| at high pressure from semi-molten material, vs liquefying
| material to be poured into a low pressure mold.
|
| Die casting has a lot of advantages, but is generally much more
| expensive as a manufacturing process, and that expense scales
| exponentially with part size.
|
| "Forging" is mostly a marketing term at this point, depending
| on the type of product you're talking about, but it generally
| refers to a combination of die casting and CNC machining.
| jameshart wrote:
| Isn't sheet metal 'stamping' a forging process? I'm not sure
| it _only_ has a marketing meaning these days. But then the
| only time I see stuff marketed as 'forged' these days is
| typically 'drop forged' tools, and I realized I also have no
| sense of what process 'drop forging' might involve. I guess I
| vaguely assumed some sort of drop hammer?
| jonshea wrote:
| Your comparison to inject molding is correct. The press is used
| to hold the die mold halves together. I enjoyed this video that
| explained the process https://youtu.be/FUsicN-wKoY?t=234
| bannedbybros wrote:
| [dead]
| flerchin wrote:
| Hydraulic Press Channel needs this immediately. Lauri only goes
| to ~140 tons.
| Awelton wrote:
| Looks like in the case of minor body damage you will have to cut
| and flush weld patches in the body instead of bolting on a new
| panel like they currently do. Aftermarket modular body panels are
| extremely cheap, and repairs consist of spraying a new panel and
| removing and installing a couple bolts and clips. This new method
| will make car manufacturers more money but will inevitably drive
| insurance and repair costs higher. This is a negative for car
| buyers, and the cheaper manufacturer costs won't necessarily be
| reflected in sales prices. There have been tons of manufacturing
| breakthroughs in the last few decades that have made vehicles
| cheaper and easier to produce and prices just keep getting higher
| and higher.
| ajross wrote:
| "Minor body damage" usually means paneling and brackets.
| _Chassis_ damage to aluminum frames almost always means
| replacement AFAICT, which for all but the newest cars is more
| than the cost of replacement anyway. Remember also that modern
| crumple zone design deliberately sacrifices the frame as part
| of the collision for safety reasons.
|
| Basically, this doesn't seem right to me. If you're hit hard
| enough to bend the frame, your car is totalled anyway. And
| that's the way we want it.
| mschuster91 wrote:
| > Basically, this doesn't seem right to me. If you're hit
| hard enough to bend the frame, your car is totalled anyway.
| And that's the way we want it.
|
| It's horribly wasteful from a resource usage perspective,
| because now you have to throw away the rest of the car - you
| can't even, say, splice together a new car out of one that
| has a bent front and one that has a bent back.
|
| Everything in society moves towards easier and cheaper
| manufacture, but at the same time to dramatically lower
| repairability, and that's just Not Good At All.
| londons_explore wrote:
| > wasteful from a resource usage perspective
|
| The materials in a car are pretty recyclable. Aluminium and
| steel especially so.
|
| The biggest environmental cost of a car is arguably the
| _people_ who put it together. Ie. the emissions of the
| person who put it together, and his house and family.
|
| If you use fewer people to assemble a thing, the
| environmental emissions go down (if you count human labor
| as having associated emissions).
| mensetmanusman wrote:
| It's more wasteful if someone dies driving a 'repaired'
| vehicle that shouldn't have been repaired in the first
| place.
| NotYourLawyer wrote:
| > you can't even, say, splice together a new car out of one
| that has a bent front and one that has a bent back
|
| Nobody was doing this anyway.
| HideousKojima wrote:
| I mean I once saw an episode of _Pimp My Ride_ where a
| guy was driving together a car made from 2 cars welded
| together, but it 's definitely not standard practice
| NotYourLawyer wrote:
| Ok not _nobody_. But effectively nobody.
| kube-system wrote:
| There used to be shops that would "weld on a new front
| clip". I know someone who had _insurance_ pay for this
| type of repair on a unibody car in the late 80s. Not as
| common in the US anymore, but if you peruse youtube
| autobody videos you can find shops in asia and the middle
| east doing these repairs on late model vehicles.
| ajross wrote:
| To keep you from dying, though. This isn't a phone. If you
| want to make an efficiency-based argument against personal
| automobiles from first principles, I'm right behind you.
| But given that we're going to drive them around, I'd rather
| drive ones that kill fewer people; even if it means having
| to recycle a bunch of frames.
| TheSpiceIsLife wrote:
| > now you have to throw away the rest of the car
|
| You ever been to an auto wrecker?
|
| Not much gets thrown away.
|
| Eventually whatever's left will go to a metal recycler.
| Steel, aluminium, copper, it's all extremely recyclable.
|
| There'll be some plastic waste, sure, but we can just bury
| that if there's no good recycling option.
| stetrain wrote:
| They aren't casting the body panels, rather the subframe that
| the body panels are attached to.
| jackmott42 wrote:
| These giga-pressed components are distinct from the body
| panels.
| bryanlarsen wrote:
| Bent structural components are almost invariably a write-off no
| matter what kind of car you have.
| TheSpiceIsLife wrote:
| It depends.
|
| I did Au$10,000 to a car valued at $12,000, almost all of the
| damage was non-visible suspension and structural.
|
| The quoting repairer had high confidence in the repairs
| before starting, so the insurer went ahead.
|
| The car drove like new after the repairs, dead straight,
| smooth af.
|
| If even a small fraction of that damage had been on, say, the
| pillars it'd had been a write off.
| ape4 wrote:
| Is it repairable? (genuine question)
| gadflyinyoureye wrote:
| Seems to result the car being totaled.
| https://teslamotorsclub.com/tmc/threads/t-boned-totaled-or-w...
| dawnerd wrote:
| I was tboned in my brand new s (there's a thread on it on
| tmc)and they finally declared it a loss after three months.
| Looking at it didn't seem like that much damage but yeah once
| the frame is even slightly skewed it's done.
| sliken wrote:
| The equation is a bit different for Teslas. The battery or
| even a fraction of a battery has substantial value on the
| used market. There's even a section on ebay just for Tesla
| batteries.
| pixl97 wrote:
| In general most modern cars are totaled when the unibody
| construction gets bent. The car gets written off by insurance
| and sold at an auction for low price. The repair people
| typically buy 2 cars and weld them together if possible.
| Otherwise the unit is parted out.
|
| No real idea on how this would work on a Tesla though.
| londons_explore wrote:
| > . The repair people typically buy 2 cars and weld them
| together if possible.
|
| The repair people also commonly just straighten out the bent
| part and resell (sometimes shipping overseas first to a place
| where less attention is paid to bent crumple zones)
| creaturemachine wrote:
| And outside the purview of consumer protection services
| such as Carfax.
| jcampbell1 wrote:
| It is pretty similar. A bunch of stamped, then bent pieces of
| sheet metal all welded together isn't more or less reparable.
| We are talking about frame components here, and so repairs
| require using hydraulics to bend the components back to
| straight'ish and then weld gussets to hold it in place.
| Regardless of the manufacturing technique, most insurance
| companies will total the car if these components get bent.
| KaiserPro wrote:
| so if you fuck the subframe (the single casting that hosts the
| motor and rear wheels with suspension) and you somehow manage
| to not break anything else, then its replaceable by unbolting
| it: https://youtu.be/uoJWjhqjq2k?t=365
|
| this is from a JAAAAAAG. but its the same idea.
| Idiot_in_Vain wrote:
| During WW2 Germany had the biggest steam presses in the world -
| allowing them to build airplanes from bigger components pressed
| into shape, while all the other countries had to use a lot more
| smaller components bolted together. Made Nazi planes lighter and
| stronger than what every one else had.
|
| All these presses where in East Germanay (mostly Berlin and
| Brandenburg) and after the end of WW2 felt in Soviet hands,
| together with plans for even bigger presses - which the Soviets
| did build. The British Empire was so short on cash at the time
| that they sold their jet engine designs to Stalin. Good frames
| and good jet engines made Soviet jets at least equal to the
| American in the 1950s.
| steve76 wrote:
| [dead]
| seydor wrote:
| They are great until you take a look at the price of aluminum
| xnx wrote:
| Aluminum holds its value
| ajross wrote:
| I did, actually. Looks like aluminum is down about 60% from a
| peak last year, and sitting about 20% higher than its pre-
| pandemic level (which inflation-corrected isn't much of a
| change at all).
|
| Is there a specific point you're trying to make? Or you're just
| saying steel is cheaper?
| seydor wrote:
| No i mean the machines are great but the war is making the
| cost of cars uncertain and probably high
| alfor wrote:
| It's mostly stored electricity and completely recyclable.
| robocat wrote:
| Sure, pure aluminium is.
|
| Surely the Tesla parts will be special alloys to get the
| correct plastic deformation during crashes (amongst other
| constraints).
|
| I would guess special alloys could require different
| recycling paths, or recycling to lower value impure
| material?
|
| Then again, it must be a solved problem, which I should
| bing!
| HPsquared wrote:
| Car structures are often made of aluminum anyway, do these
| parts use significantly more than e.g. bonded extrusions?
| dsfyu404ed wrote:
| These presses are for complex and fairly thick structural
| parts. Think like radiator core supports, subframes,
| dashboard support structures and control arms. Yhe resultant
| parts are substantially more expensive than the stamped and
| welded steel they replace. The range of cost difference vs
| steel also wide because the complexity of the part and the
| shape of the part affect the service life and initial cost of
| the die a lot. Some parts lend themselves well to the
| process, some don't. What this increased expense buys you is
| weight and NVH improvements.
|
| In previous cases aluminum has been used for car bodies and
| cosmetic sheet-metal panels. The cost difference vs steel is
| not nearly as large in that application.
| bluetomcat wrote:
| Big car manufacturers use their own modular platforms for the
| chassis of different vehicles, in order to optimise R&D and
| production costs. An upsized vehicle from the range usually
| uses the same basic platform with a few size adjustments here
| and there. "Gigacasting" would require them to create moulds
| for every individual part.
| hef19898 wrote:
| Seems by using "gigacasts" Tesla is kind of limiting the
| use of cross-model platforms... Interesting approach to
| ignore one of the most beneficial automotive principals,
| and being lauded for it.
| seydor wrote:
| > cross-model platforms
|
| and spare parts
| pixl97 wrote:
| Weight is negative fuel and must be considered in the equation.
| londons_explore wrote:
| With a typical car having 200kg of aluminium, thats $400.
| Substantial, but not massively so for the chassis of a $60,000
| car.
| jiggawatts wrote:
| I made a similar argument to explain that science fiction
| technologies like "asteroid mining" won't improve the cost of
| everyday products like cars. Even if the material costs were
| reduced to _zero_ , the sticker price would remain
| essentially unchanged.
|
| Elon Musk made a similar point about the inefficiency of
| NASA-style rocket construction. The "raw materials" to make a
| rocket cost something like $500K, but the completed launch
| vehicle is often north of a billion dollars. The SLS program
| currently costs a whopping $4B per launch! Even if you got
| all the "expensive" materials like titanium or carbon fibre
| _for free_ , the SLS launches would still cost too much.
| 01100011 wrote:
| EV passenger vehicles are great until you look at the supply of
| copper.
|
| Seriously, I love my car, but I also understand that we can't
| have everyone in one. Mass transit, walking, biking, e-bikes,
| etc... These are all competitors to EVs and unless we have a
| revolution in production requiring less copper or increases in
| copper supply, coupled with large increases in energy
| production, we're not giving everyone a cheap EV and the sort
| of mobility ICE drivers have had over the last 100 years.
| scythe wrote:
| Google indicates that a typical electric car contains 183
| pounds of copper. That's a lot! But a typical house contains
| 470 pounds. That's even more. So I'm not convinced that cars
| alone will dominate the market for copper.
| mikewarot wrote:
| 9,000 tons is a lot of force... but we've done much bigger
| presses[1]
|
| I fail to see how the prefix "Giga" - 10^9 applies.
|
| [1] https://en.wikipedia.org/wiki/Alcoa_50,000_ton_forging_press
| londons_explore wrote:
| I don't think those presses would be suitable for car
| manufacturing because they weren't fast... Ie. rather than a
| cycle time of ~50 seconds, they had a cycle time of many hours.
| mikewarot wrote:
| What makes you think they had such a slow cycle time? I can't
| find any hint of that, there are videos showing cycle times
| with a part only taking a minute or so.
| pif wrote:
| 1000 tons = 10^9 grams
| blamazon wrote:
| The encompassing "heavy press program" is an interesting bit of
| history:
|
| https://en.wikipedia.org/wiki/Heavy_Press_Program
|
| Several of these presses have been designated by the American
| Society of Mechanical Engineers as historic landmarks and I
| suspect the HN audience may be interested in the other
| landmarks:
|
| https://www.asme.org/about-asme/engineering-history/landmark...
|
| I've been trying to visit as many of these in person as I can
| and it's been a very satisfying hobby. Some portion of them are
| on private land or don't have standard visitor hours, but my
| tip is group tours are easiest to arrange for the most reticent
| property owners, and there's almost always an ASME chapter at a
| nearby university looking for industry mentor connections. Plus
| going on a field trip with students is a special joy :)
| bryanlarsen wrote:
| 9,000 tonnes is 9 Gigagrams.
| mikewarot wrote:
| so, 9 Kilotons they should call it the KiloPress
| idontwantthis wrote:
| Everything is giga-something.
| playingalong wrote:
| Right. But to their defense, gram is the unit without
| prefix.
| bitwize wrote:
| So we're building real cars the way we manufacture Hot Wheels?
|
| Neat. We're living in the Gunbuster future, in which mecha were
| shipped in giant blister packaging and spaceship parts came on
| huge plastic model kit rails.
| kjksf wrote:
| Fun fact: Musk says that when Tesla was thinking about doing
| gigacasting, they called 6 suppliers of those machines asking if
| they can make 6 gigaton machine (which didn't exist at the time).
|
| 5 out of 6 said "no" and 1 said "maybe". I'm guessing that
| "maybe" was IDRA and they made 6 gigaton, then 9 gigaton (already
| in Texas for making Cybertruck) and there are rumors of 12
| gigaton machine in development.
|
| Another fun fact: Tesla body line pre gigapress was 1000 robots.
|
| Doing front casting removed 300 robots, rear casting another 300.
|
| So Tesla saved 600 out of 1000 (60%) robots, so the line is
| shorter and faster.
| selectodude wrote:
| That doesn't make a whole lot of sense. Telsa uses pretty much
| off the shelf die-casting machines from Idra Group in Italy.
| The "giga" part of it is just the same sort of parlance as
| "giga factory" to make batteries.
|
| You can even buy your own "gigapress".
|
| https://www.idragroup.com/en/gigapress
| mensetmanusman wrote:
| Idra made a new widget for Tesla that other widget makers
| thought was too risky to attempt.
|
| Now these widgets are on the shelf. Giga is a marketing term
| related to doing something at a scale that has never been
| done before (& related to EVs).
| dylan604 wrote:
| >Giga is a marketing term related to doing something at a
| scale that has never been done before
|
| So, it's 21st century tech then?
| jabl wrote:
| > Giga is a marketing term related to doing something at a
| scale that has never been done before
|
| Eh, the Heavy Press Program produced 50000 ton press forges
| in the mid-1950'ies (granted EV's weren't a thing then).
|
| Kind of amazing, a machine the size of a 4-story building
| that can bench press a battleship.
|
| https://en.wikipedia.org/wiki/Heavy_Press_Program
| elil17 wrote:
| Heavy press program was amazing.They actually had to
| worry about the seismic waves created by the press. About
| 10x larger than the "gigapress."
| selectodude wrote:
| Important to remember that these aren't presses, they're
| die-cast machines. Totally different technology.
| bagels wrote:
| What a misleading name! Apparently, it's kind of both a
| press and a diecast machine. It does pressurized castings
| with really high clamp force.
| toomuchtodo wrote:
| Sandy Munro's teardown of one of the first Model 3s (circa
| 2019) and his advice to Tesla in ~200 initial manufacturing
| improvements was integral in shifting their manufacturing
| strategy (and also led to the termination of the person who
| designed the body). A more recent 2021 teardown has a lot of
| praise for the latest build quality.
|
| https://www.teslarati.com/tesla-model-3-sandy-munro-analyst-...
| ("Tesla and Munro have since communicated, with the auto
| veteran sending the electric car maker a list of over 200 pro
| bono suggestions that could improve the Model 3's body, which
| he believed was over-engineered. Munro himself spoke with Elon
| Musk, who explained that the person responsible for the Model
| 3's body design had been terminated. In response, Munro told
| the CEO that the response was "not fast enough," since Tesla
| "never should have hired (the engineer)" in the first place.")
|
| https://www.teslaoracle.com/2021/01/26/2021-tesla-model-3-sa...
| ("2021 Tesla Model 3 is as good as anything you could find out
| of Europe, says Sandy Munro")
| YeahNO wrote:
| Not really fair to blame the engineer. Musk is the one who
| hired the engineer to lead the design of the Model 3, knowing
| he had no experience with vehicle manufacturing design. They
| wanted to "move fast and break things" like a tech company.
| It was an expensive learning process for Musk. A mistake he
| seems to repeatedly make.
| adolph wrote:
| The engineer had no experience with vehicle manufacturing
| design?
|
| https://electrek.co/2021/01/25/tesla-loses-best-
| engineering-...
|
| https://www.engadget.com/2018-07-02-tesla-engineering-
| lead-d...
| dumpsterlid wrote:
| [dead]
| realworldperson wrote:
| [dead]
| elil17 wrote:
| Perhaps you mean kiloton! A gigaton is a lot (like, a cubic
| kilometer of water).
| twic wrote:
| They may be gigapresses, but those forces are in kilotonnes,
| not gigatonnes.
| mNovak wrote:
| Actually surprised no one is taking up the "gigagram" 9Gg
| moniker
| intrasight wrote:
| Dirty robots - sold dirt cheap
| jameshart wrote:
| Maybe this suggests the mindset he had when he got to Twitter
| and started complaining about how many micro services they had.
| "Maybe I can call up IDRA and get them to replace all these
| microservices with one gigaservice..."
| sonofhans wrote:
| One things this means is that cars are going to become as
| disposable as cell phones and laptops. As cars get assembled from
| larger components, damage to one area of the car will have larger
| effects. This will increase repair costs, more often pushing them
| over the limit to declare the car a total loss.
|
| I can't quickly find the numbers, but I know that car repair
| costs are going up and repair rates are going down, and have been
| for decades. The reason is obvious: the benefits of a modern car
| come at a cost. E.g., cars are much safer now, partly thanks to
| airbags; those are expensive to replace. My car has 11 airbags,
| and if they all popped off at once that alone would probably
| total it.
|
| Years ago I was in a collision which bent that frame of my car.
| That's usually game-ending, but this car has a modular frame, so
| they just bolted on a new frame component. Now, Mercedes have
| always (until lately, perhaps) been known as highly-repairable;
| it's one reason they last so long.
|
| So it's good that the right-to-repair movement is getting
| traction. We're going to need to point it at cars soon, and for
| mechanical reasons.
| pengaru wrote:
| One could make the same argument about batteries in EVs making
| cars more disposable. The insurers are going to total any
| vehicle having the slightest damage to its battery module
| between the high risk of incorrectly assessing its safety, and
| its high cost of replacement...
| elif wrote:
| If you bend a frame rail in a composite structure, you have x
| new welds you have to perform, y rivets, z bolts, w plastic
| pins and spacers.
|
| Some of those attachments were not designed to be removed and
| performed again, so you're looking at removing and replacing
| otherwise okay parts and then probably realizing that some
| other piece is slightly out of alignment and can't safely be
| reused...
|
| If you bend a a unibody casting, firstly there is a larger
| chance that it is non-critical since there is so much added
| mass and structure. It is not a series of dominos like in a
| composite.
|
| Secondly, all the attachment points are cast into the part.
| Replacement of one large piece is a significant reduction in
| effort, and results in more confidence in the ultimate repair.
| winrid wrote:
| That "one large peice" is literally the entire unibody. You
| going to re-shell a street car like a racecar?
| dsfyu404ed wrote:
| >Some of those attachments were not designed to be removed
| and performed again
|
| Just because the OEM didn't bother to figure it out doesn't
| mean nobody can. There's all sorts of trick specialty repair
| parts and procedures in the aftermarket autobody industry to
| fill the gaps the OEM couldn't be bothered to.
| fiftyfifty wrote:
| If you look at the breakdown of the Model Y with the casted
| front end and back end by Munroe on Youtube it's fairly
| modular, with a front end cast and back end cast both bolted to
| the battery pack in the middle, and the top of the car lowered
| onto the base. If one of these casts were damaged in an
| accident but the rest of the car was OK, it might make more
| sense to just replace the entire front end or back end cast
| with a new one.
| post_break wrote:
| My Honda accord was $35,000. If the front is damaged just the
| headlights are $900 a piece. Ignoring structural issues with
| the unibody, the damage multiplier for new cars isn't the
| frame, but everything else. Headlights, fog, lights, sensors
| for adaptive cruise, calibrating the new sensor, bumper, paint,
| etc.
| function_seven wrote:
| It's insane. One of the stories about Chevrolet--when they
| were first designing the C5 Corvette--was that they took
| input from the insurance industry regarding repair costs.
|
| One example of this is the hood. The previous generation had
| a beautiful clamshell hood that wrapped down around the
| sides. Opening the hood made the front end almost look like
| an open-wheel car. But it was expensive to make in one piece,
| and the entire piece had to be replaced if any part of it was
| damaged.
|
| The C5 has a more conventional hood, with seams running along
| between the fenders and the hood panel. Not as pretty, but
| substantially cheaper to repair.
|
| So, $900 for a headlight? We need to strengthen (or better
| align) the incentives for carmakers to reduce component
| costs.
| coredog64 wrote:
| This was Saturn's big value proposition: GM used plastic
| for external body panels as they were more resilient to
| light damage and were pre-finished for cheaper replacement.
|
| Expensive insurance will also kill cars, so insurance
| companies are definitely consulted stakeholders in vehicle
| manufacturing.
| bryanlarsen wrote:
| Tesla sells insurance, so has a direct incentive to make
| its cars easier and faster to repair. Previously Tesla is
| notorious for how long it takes to get parts, but that is
| improving, partly because of the insurance incentive.
| njarboe wrote:
| Elon Musk has mentioned one reason Tesla started doing
| insurance was to get more insight into repair costs and
| processes to help improve both vehicle design and the
| repair experience.
| mauvehaus wrote:
| The first-gen Dodge Viper was notoriously expensive to
| repair for the same reason: the clamshell hood.
| notJim wrote:
| Do we though? What percentage of cars are ever in an
| accident? If the choice is between better functioning while
| working versus lower repair costs, it's not obvious why we
| would prioritize lower repair costs. People on here always
| have this idea that repair must be prioritized above all
| without considering the tradeoffs.
| jcampbell1 wrote:
| There is a huge incentive misalignment. The customer pays
| monthly for "insurance" and the moral hazard, the insurance
| company then pays a repair company, who then pays the OEM
| for the headlight.
|
| The games all go away when the manufacturer sells the
| insurance, estimates how safe the driver is with data, and
| then handles the repairs.
|
| Tesla understands this and sees it as a way to beat the
| competition on total operating cost for the customer.
| kube-system wrote:
| I don't understand why more people don't check insurance
| rates before buying a car.
| coredog64 wrote:
| Insurance rates will eventually be reflected in the way
| the market prices the car. It would be more efficient if
| people checked, but the current process is close enough.
| dsfyu404ed wrote:
| Because the difference from model to model is a) not that
| high when cross-shopping models of the same form factor
| b) outweighed by demographic correlation factors.
| kube-system wrote:
| People do cross shop different classes of vehicle, but
| even within a particular vehicle class, the differences
| can be easily be more than enough to be an important
| factor in purchasing. If you're comparing two vehicles,
| and one is $1000 cheaper to purchase, but costs 20% more
| on insurance... it likely isn't cheaper by the time your
| loan is paid off.
| Wistar wrote:
| On a BMW 760i (V12) the driver's side LED/laserlight
| headlight lens was badly fogged. These are sealed units and
| not repairable. Cost to replace? $9,600. It was covered under
| factory warranty but... whoa.
| DaveExeter wrote:
| That's just BMW cheating customers. Or you might argue that
| they are cheating insurance companies, since most crunched
| headlights are replaced under insurance.
| [deleted]
| BizarroLand wrote:
| Yep. You may not be able to get it to Brand New Out of
| the box OEM shine but I bet there are a dozen
| acetone/sandpaper/lacquer/toothpaste/hydrogen peroxide
| something or anothers that could get you to 99% of new
| quality for less than $20.
| LeonM wrote:
| Headlights are considered safety critical. None of the
| manufacturers will (and should!) allow a certified
| mechanic to rejuvenate and reseal a headlight unit under
| factory warranty. A manufacturer will always replace the
| unit, just to be able to warrant the repair.
|
| You can DIY it of course, but no BMW 760i owner is ever
| expected to do that.
| BizarroLand wrote:
| Under warranty? Sure, let the manufacturer handle it.
|
| Outside of warranty? Don't give a company 10 grand for 74
| cents worth of plastic and chrome.
| dsfyu404ed wrote:
| > These are sealed units and not repairable
|
| Not repairable by a minimum effort flat rate tech in the
| US...
|
| There's probably some guy in Latvia that has a Youtube
| instructional on how to re-seal it or something. $9600 is a
| hell of a motive to figure out how to repair it.
| SECProto wrote:
| > I know that car repair costs are going up and repair rates
| are going down, and have been for decades. The reason is
| obvious:
|
| Have you taken a car in for repair recently? I agree that the
| reason is obvious - parts labour costs make it no longer make
| sense. Just a brake job nowadays costs a thousand dollars or
| more (depending on car model etc), i.e. 3% of a brand new
| vehicle purchase price. There's no anti-features causing this,
| it's just labour charges increasing.
| patwolf wrote:
| I read an article, probably a decade or more ago, about how bad
| it would be for NYC cab companies that Ford was discontinuing
| the Crown Vic. The reasoning was that repair costs would
| increase because it was the last vehicle where individual body
| panels were easily replaceable. It was also the last body-on-
| frame sedan, so you could feasibly swap out an entire chassis.
|
| I'd be curious what the long-term impact was, or whether Uber
| made all that irrelevant.
| Scoundreller wrote:
| Probably still cheaper to operate a Corolla, especially when
| everyone on the planet knows how to fix them.
| eternityforest wrote:
| Most cars don't seem to fail because of structural damage. How
| relevant is repairability?
|
| Is the expected material use and expected cost to the consumer
| more or less for repairable vs gigapress?
| bryanlarsen wrote:
| The reason that your Mercedes was worth repairing was because
| it was so expensive. Most cars get written off with $15,000
| worth of damage simply because most cars aren't worth $15,000.
| sonofhans wrote:
| Actually, I got it used for about that amount, and many years
| before the collision. You may not know -- forgive me if I'm
| wrong -- but damage to a car frame totals the car. Frames
| have crumple zones, the activation of which destroys that
| part of the frame. No insurance company will sanction repair
| of it.
|
| This only worked because the frame was modular to begin with,
| a rarity, so they could replace only the damaged part. IOW
| the car was built to be repairable. This increased its final
| cost, but means that it's still on the road today, rather
| than in a scrapyard.
| dylan604 wrote:
| >You may not know -- forgive me if I'm wrong -- but damage
| to a car frame totals the car.
|
| This is a pretty safe general rule, but it is not absolute.
| I had a brand new truck < 6 months old where I was hit from
| behind in stop-n-go traffic. The insurance company did not
| want to total it because the repair could be made for less
| than the value of the total. I asked how a frame could be
| repaired, and they just said it can be done. My counter was
| that the vehicle would now show frame repair and would have
| no value for trade-in nor would someone other than less
| than reputable dealers offer a car with repaired frame
| damage.
|
| So, depending on the insurance company (Progressive was
| pushing for the repair. I hate Flo), some will argue
| against frame damage being an automatic total.
| YeahNO wrote:
| I've had a car in a crash that should've been totaled. I
| was rear-ended by a truck while stopped about two months
| after my previous car was totaled (t-boned by an drunk
| driver). The insurance company balked at a 2nd total in
| that time period and demanded it be repaired. The total
| repair cost came to almost $5,000 over the KBB value. The
| rear end had been accordioned and the repair company
| straightened it out (you can indeed straighten frames
| with the proper alignment tooling) having to replace all
| the panels past the doors. They claimed it was back to
| spec, but it never tracked correctly in turns after the
| repair job. I sold it shortly after for about what I
| paid.
| joering2 wrote:
| > I sold it shortly after for about what I paid.
|
| How did you manage to do that? Was that in USA? I presume
| damage was on record with CarFax, etc. Did you tell new
| owner what happened to the car?
|
| Finally - if you were able to show the car does not track
| correctly, wouldn't that be enough to re-open the claim
| and go back to your insurance company to properly fix it
| (most likely replace it at this point?)
| mauvehaus wrote:
| Frame is a very different concept between a pickup truck
| and a Benz. Nearly all pickups are built as body-on-
| frame, where there's a separate chassis that mounts all
| the mechanical bits, and then the body goes on that.
| Nearly all sedans, wagons, and things that most people
| would consider "not trucks" are unibody. The body and
| frame are one and the same. The Benz in question likely
| had a detachable subframe at the front or rear where the
| mechanical bits are attached. It's pretty common to have
| bolt-on frame members (cross members especially), a fully
| detachable subframe forward of the firewall is less
| commmon.
|
| All that to say, they can sometimes straighten a body on
| frame vehicle. Whether this is a good idea or not
| obviously depends on the severity of the damage. If a
| frame rail is bent into a banana shape, probably not. If
| there's been some light shearing or twisting movement of
| one rail to the other, they can probably do it safely
| within limits. Remaining imperfections get taken up in
| the suspension (it's adjustable). If you wonder how they
| put race cars back on the track so fast, it's because
| they'll tolerate a lot of frame geometry out of spec if
| they can make it up in the suspension without otherwise
| compromising safety and handling.
|
| All that said, all of your points about the reduced value
| of the truck are certainly true.
| sacrosancty wrote:
| [dead]
| nradov wrote:
| Repairability for collision damage is a lost cause. Let's focus
| on collision _prevention_ instead. The latest generation of
| Advanced Driver Assistance Systems are already bringing
| collision rates down for newer cars and there is much room for
| improvement.
| jollyllama wrote:
| All of the comparisons involved will probably be for unibody /
| monocoque vehicles, but comparisons to body on frame (Crown
| Vic) would be interesting.
| mauvehaus wrote:
| I was talking to a body shop about unibody construction in the
| context of some rust repair several years ago. Basically, for a
| lot of cars, if it isn't a bolt on part, it's already supplied
| as one big piece from the manufacturer. Like, the whole side of
| the car sized piece. Whether that's one stamping or several
| welded together (or bonded), it's a cut and weld job for a
| collision repair. A small enough rust repair can be made up
| from sheet metal, but not a serious collision.
|
| Also: paint. It's never one panel. They usually have to feather
| in the color on the adjacent panels because getting a perfect
| match is tough despite computers, etc. You need one panel
| painted, and you're pretty quickly looking at getting 3 or 4
| painted (or at least attended to). Even discounting airbags, it
| doesn't take much to total out even a five to seven year old
| car these days.
| kjksf wrote:
| Munroe addressed this complaint and his point was: if the
| collision is bad enough that it damages that cast, it would
| total a non-cast car as well.
|
| Plus you have to reason on the level of systems, not
| components.
|
| Single-piece rear casting replaces 70+ parts.
|
| Those parts have to be welded together by robots.
|
| Each weld is a potential failure point.
|
| Casting produces more reliable car with less variances which
| ends up lowering repair costs on global (system) level.
|
| https://twitter.com/Tesla/status/1513886756923445254
| dsfyu404ed wrote:
| >if the collision is bad enough that it damages that cast, it
| would total a non-cast car as well.
|
| This is just lunacy.
|
| It's absolutely possible to locally damage a cast item in a
| manner in which a welded/bolted steel assembly would also be
| locally damaged. And the cast is going to be harder to
| repair.
| lallysingh wrote:
| Who's going to do that weld and then take liability for the
| safety of the car after?
| linuxftw wrote:
| Lots of older cars are rolling around with suspect welds
| today, often times performed by amateur welders. Everyone
| understands a repaired car might be be exactly same as
| new.
| dsfyu404ed wrote:
| The people performing their work and their insurer, just
| like literally every other case where skilled labor is
| bought.
|
| Contrary to internet screeching welding the kind of cast
| alloys used on cars isn't really a big deal especially
| the aluminum ones (iron is harder). If the business case
| materializes I'm it will become common just like aluminum
| body repair.
| hef19898 wrote:
| Someone has not that much knowledge about casting nor welding
| it seems.
| Loughla wrote:
| Expand on that comment, please.
| djbusby wrote:
| Which one? I can't tell cause i don't have experience.
| numtel wrote:
| Probably because welds are usually stronger than the
| materials they are binding.
|
| As far as casting, I would imagine that would result in
| more brittle components that would snap instead of bend
| in a crash.
| galangalalgol wrote:
| That depends on the metal and if it is post treated.
| Welded aluminum isn't as strong as the cast/extruded and
| heat treated pieces. Welding on 4130 steel can easily
| produce weaker joints if those joints are then treated.
| If they have an economical way to heat treat an entire
| cast piece, that might make it stronger than welded bits.
| hef19898 wrote:
| Heat treatment of modern, stabdardized alloys is a
| scirnce. Doing so with complex formed parts is still a
| bitch so. Especially big parts. Personally, I think
| induction hardening might work.
|
| Well, welded structural parts, even produced in high
| vilumes, are a rather well understood problem so.
| baybal2 wrote:
| [dead]
| adolph wrote:
| _The most common type of forging equipment is the hammer
| and anvil. Principles behind the hammer and anvil are still
| used today in drop-hammer equipment._
|
| _A forging press, often just called a press, is used for
| press forging. There are two main types: mechanical and
| hydraulic presses._
|
| https://en.wikipedia.org/wiki/Forging#Equipment
| causi wrote:
| _Munroe addressed this complaint and his point was: if the
| collision is bad enough that it damages that cast, it would
| total a non-cast car as well._
|
| I don't see how that's possible. Grain structure and
| alignment make forged parts much stronger than cast for a
| given weight.
|
| http://www.expansion-
| parts.com.tw/upload/web/MetalPowderPart...
| interstice wrote:
| Should this not be a comparison to stamped /welded metal
| since that's what car manufacturing generally uses?
| abc_lisper wrote:
| Can one align the grains by magnetizing the cast (aluminum
| is para magnetic)
| pengaru wrote:
| Very few parts of any automobile are forged. Even then it's
| usually high performance variants of ICE vehicles, limited
| to the engine internals, and transmission/differential
| internals.
|
| Having said that though, the sheet metal used in unibody
| construction is far more ductile than _usually_ brittle
| castings. If they 've developed new alloys making the large
| castings more ductile than previous castings, it might not
| be a problem.
| bagels wrote:
| It's mostly going to be internal engine/gearbox parts
| that are forged, and possibly wheels.
| sliken wrote:
| The structural part of cars, at least any in the under
| $100k range, are not made of forged parts.
|
| Sure various high stress suspension pieces are forged, but
| those aren't the ones being replaced by die cast
| assemblies.
| A_D_E_P_T wrote:
| That's not at all true. Critical structural parts, such
| as B-pillars, are almost always made of forged or hot-
| stamped high-strength steels. And this is true even in
| cheap vehicles like the 2007 Dodge Caliber. See, e.g.:
| https://i.imgur.com/N399WLV.png
|
| I think that the casting technique mentioned in the
| article is primarily, or entirely, for non-structural
| parts that would otherwise be made of something akin to
| mild steel.
| Robotbeat wrote:
| No, the aluminum injection castings are structural. Using
| high pressure injection helps keep the voids low or non-
| existent compared to atmospheric pressure sand casting,
| for instance, which significantly improves performance
| (improving strength and toughness).
| mensetmanusman wrote:
| Tesla's leadership here is incentivizing huge efficiency gains
| which will help the world adopt EVs much faster than otherwise.
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