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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 ha
by kjksf 4y ago
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 https://twitter.com/Tesla/status/1513886756923445254
- hef19898 4y ago[flagged]
- Loughla 4y agoExpand on that comment, please.
- djbusby 4y agoWhich one? I can't tell cause i don't have experience.
- numtel 4y agoProbably 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 4y agoThat 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 4y agoHeat 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 4y agoExplaining, the "gigapress" is not a press, it's more of an injection moulding machine for aluminium. That's the biggest outrage. This is the real metal press: https://youtu.be/iZ50nZU3oG8 https://youtu.be/iZ50nZU3oG8 And what Elon called a "gigapress" is also not related to more familiar semi-solid metal casting, as the alloy used has no thixotropic properties, but more regular casting under pressure.
- adolph 4y agoThe 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 https://en.wikipedia.org/wiki/Forging#Equipment
- ketralnis 4y agoThis is least useful way to express what you're trying to say
- ketralnis 4y agoThis is least useful way to express what you're trying to say. It just says "I'm smarter than you" while adding nothing.
- causi 4y agoMunroe 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/MetalPowderParts/grain_flow_1.jpg http://www.expansion-parts.com.tw/upload/web/MetalPowderPart...
- interstice 4y agoShould this not be a comparison to stamped /welded metal since that’s what car manufacturing generally uses?
- sliken 4y agoThe 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 4y agoThat'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 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 4y agoNo, 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).
- MichaelZuo 4y agoNo part of significant size will be forged in a sub $100k car. As another user mentioned, even the cheapest forged wheels are >>$1k each.
- dsfyu404ed 4y ago>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 4y agoWho's going to do that weld and then take liability for the safety of the car after?
- linuxftw 4y agoLots 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 4y agoThe 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.
- skellington 4y agoBut almost nobody does it and insurance companies just total cars that have this kind of damage. Yes, in theory, it can be repaired but it's too expensive and because it's hard to guarantee the correctness of the repair, insurance companies don't do it and most consumers wouldn't stand for it.
- dsfyu404ed 4y agoIt's the labor cost that makes it non-viable in most cases. If it penciled out economically then all the people who are outsourcing their thinking to their insurance company would automatically become fine with it. There is nothing about it harder to guarantee than anything else in the autobody business. How do you know they're applying panel bonding adhesive properly? You don't.
- rad_gruchalski 4y agoIt’s pretty funny seeing a post from Tesla right after a line about „less variances“. It’s a common knowledge by now, posted many times here, that Tesla build quality and parts passing depend on the phase of the Moon and the menu at the factory.