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Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

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Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#141

Post by DEinspanjer »

squigs25 wrote: post #63

It's really difficult to emphasize how excessive this is. As a mechanical engineer, I knew just by reading the title that this is really excessive, because the titanium alloy used is definitely a marketing stunt. Titanium has unbelievable tensile strength for its weight, but there's no good reason to make an "underbody shield" out of titanium except for publicity. It would make way more sense to use steel (and maybe…

What are the characteristics of Titanium regarding corrosion and wear? One thing I have heard from several of the highly technical owners on the forums is that one of the reasons for the design choice of a mostly aluminum body is that there is no structurally weakening corrosion in reasonable use of the vehicle, even in areas that use a lot of salt and such on the roads.

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#142

Post by makomk »

Cthulhu_ wrote: post #78
loceng wrote: post #25

Earlier quoted context omitted.

Exactly why. They're gently poking fun that Tesla vehicles are extremely safe, especially compared to fires - and then sticking it to critics further by actually announcing improvements to further reduce the already very low numbers of fire and further increase the already highest rating ever for a safety check for a vehicle. Well done Tesla and Elon.

And yet, I can't help but feel they're being very, very defensive over it. I can't blame them, of course, given how something trivial like a car fire (trivial given the average frequency of them) is turned into a national news event. At the same time, Tesla's attention to quality and perfection and what-have-you will end up in them being heavily scrutinised. It's not that different from Apple in that respect; random…

It's entirely possible they know something we don't - like the results of the investigation into the Tesla fires - and are trying to get this story out ahead of something more negative. It'd certainly be a smart move.

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#143

Post by symmetricsaurus »

revelation wrote: post #131
symmetricsaurus wrote: post #91

Earlier quoted context omitted.

What I actually want to know is if you had the same number of other average cars driving the same distance as the Teslas, how many people could you expect to be killed in these cars. Here is my crude estimation. If we consider that there are 3.2 * 10^-4 people killed in traffic per car per year[1] and that there are 20000 Tesla Model S on the road[2], then we get that there should have been about 6 deaths. Now most o…

Thats a terrible metric if you consider that some cars cost more to insure not because of the vehicle or make but simply because of the kind of people that tend to drive it.

Of course, that's why I said it was a crude estimate.

On the other hand, since the Tesla S is a quite high performance car, you could expect it to get into more accidents than the average car.

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#144

Post by DEinspanjer »

sailfast wrote: post #139
johnward wrote: post #120

Earlier quoted context omitted.

" the shields prevented any damage that could cause a fire or penetrate the existing quarter inch of ballistic grade aluminum armor plate that already protects the battery pack" Ballistic grade aluminum armor plate... If there is one thing Tesla does well it is publicity. I know there are high strength steels but it seems like they want something that is strong and light. If it sounds like something impenetrable to t…

Just for giggles, could it be that adding a heavier material such as steel would have a more significant impact on range due to the additional weight? Part of the upgrade pitch is that users only see a 1% decrease in range. With steel, perhaps you see a 3-5% decrease, and range has been the key argument for Tesla against other competitors.

0.1% decrease. Believe it or not, I know several owners who would not be satisfied with even a 1% decrease, especially if it is adding a safety feature that most of them feel is so unlikely to happen, they would have preferred never to have temporarily disabled the low height mode.

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#145

Post by mnw21cam »

kristofferR wrote: post #115
colechristensen wrote: post #45

Earlier quoted context omitted.

Titanium is more expensive than it is valuable. Most of the high cost of titanium products comes from the relatively very expensive purification process and difficulty machining.

"is more expensive than it is valuable" does not makes sense, since the value of something is what people are willing to pay for it. If it is expensive then it has a high value.

Not so. Expensive - how much it costs to make it. Valuable - how much someone else would pay for it.

So, if I was to spent loads on parts to make a relatively useless widget that fills a particular niche in my daily life, it would be expensive, but I wouldn't view it as valuable. It's only as valuable as it is expensive if there are lots of people who want it, which is not the case for custom work.

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#147

Post by gregpilling »

blisterpeanuts wrote: post #82
crusso wrote: post #52

Earlier quoted context omitted.

I realize that the suspension isn't unique to Tesla, but over-the-air software updates seem to be. It irks me to no end that I'm told that my Infiniti can't be updated to even work properly with my iPhone, much less the fact that they want to charge for gps map updates that are essentially free from Apple, Google, Microsoft, etc.

Yes. My '13 Prius V MP3 player doesn't properly randomize tracks from my flash drives. Apparently no one at Toyota tested their player with a 64 gig thumb drive with ~840 directories. I doubt Toyota will ever retro-fix the obvious software flaws. Tesla however sounds like they get it. Although many of us won't be buying an $80K vehicle any time soon, I expect that these kinds of innovations will trickle down to the m…

My Dodge Ram has an unworkable turd as a head unit also. Built-in MP3 that is painful to use, navigation that is horrible. It will never change, I am sure of it.

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#148

Post by DEinspanjer »

squigs25 wrote: post #124
blisterpeanuts wrote: post #92

Earlier quoted context omitted.

But titanium is less dense than steel, hence preferred when weight is important. For an electric car, weight is paramount, I would think.

Actually, nope! While it requires more initial force, that extra energy due to added mass is stored in kinetic energy, and contrary to popular belief, it does not affect efficiency. There was actually a myth busters episode about this. Electric cars would store this added energy in their regenerative breaking, so it shouldn't affect energy consumption. Also, the added weight of steel over titanium would be negligible…

I didn't see the Myth Busters episode, but isn't there still a loss due to the inherent inefficiency of the motor and regen breaking?

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#149

Post by johnward »

Theodores wrote: post #34
eiji wrote: post #11

I'm sorry but my first reaction is "What a waste". Titanium is ridiculously expensive for various reasons. The best these engineers could come up with is to put a sheet of metal under the car? You got to be kidding me. I see why they have to use Titanium for it, anything else doesn't work, but it shows how far away this car is from reality and from true mass production.

My feelings too. However, as much as I like steel, I find it incredible that most cars use very heavy materials, e.g. steel, instead of aluminium, plastic, carbon fibre and titanium. Such materials are common on bicycles and planes. Moving a tonne or two of steel around is a real waste, particularly when it rusts. At least with this wondercar the bottom is flat and aerodynamically sound, unlike all of those legacy ve…

Well, it's not like they can just redesign the entire platform at this point. Slapping some titanium on is probably the best move they can make right now. It should satisfy any government and customer concerns for a problem that was pretty rare to begin with.

As for the other materials we've been using them sparingly in vehicles. The new Ford F150 is using much more aluminum, enough to bring the weight down by about 900 pounds. Yet people are still criticizing aluminum as a material choice. It's not hard to see that aluminum, carbon fiber and other light weight materials are the future of vehicles. Yet some people are still afraid because they associate heavy steal with strength. That aluminum hood is the only part on my old truck that is not rusting through. Lighters, stronger, no rust. Where is the negative?

Re: Tesla Adds Titanium Underbody Shield and Aluminum Deflector Plates to Model S

#150

Post by SeanLuke »

blisterpeanuts wrote: post #140
SeanLuke wrote: post #128

Earlier quoted context omitted.

None of which has anything to do with vehicle fires, which is the topic at hand.

Vehicle fires are a potential result of collisions, no? They don't just occur spontaneously.

Sure they do. Vehicle fires occur spontaneously, due to sabotage (the most common reason), due to various acts of god, due to road debris, and due to collisions.

Anyway, two of the three Tesla fires were on freeways, not local roads. The third was under somewhat mysterious circumstances (Mexico).

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