While holding this tight of a tolerance is standard for small sinple injection molded plastic part like Lego blocks (0.01mm tol. usually need some really good tooling though), it’s not really possible to hold this tight of a tolerance for large sheet metal construction such as the Cybertruck body (Standard tolerance should probably be in the milimeter range at most. )
Also, there is no way to actually measure this tight of a tolerance on large parts such as a car, since the standard methods for this tight of a tolerance measurement is… using a caliper, as using automated optical inspection for every dimension isn’t really feasible.
So, I guess they’ll probably just coddle Musk and make some fake drawings for his eyes only or something, which would only be more useless work for Tesla people.
Also, there is no way to actually measure this tight of a tolerance on large parts such as a car, since the standard methods for this tight of a tolerance measurement is… using a caliper, as using automated optical inspection for every dimension isn’t really feasible.
We definitely have lasers that can measure this tolereance.
And if Musk gets too involved somewhere, they just drop a couple of cool words and get him to go on a wild goose chase about shooting people through a massive vacuum canon or something stupid like that.
Even the heat of the day would make a panel warp more than is being stated. It is just sales BS to make him look good.
No two cars are ever the same. Even with robots panels move in jigs. There is usually a guy at the end of a line who has the job of body adjust. Paint shops warp the crap out of a car body in the baking phase.
Maybe all this is on purpose so he can blame the factory workers on why the product never materialize and he can avoid the shame of having unsold inventory as people realize the car is fugly
Expect that this is total BS, either because he watched some episodes of “how it’s made” and had to immediately share the profundity with his brilliant engineers as a lame flex, or he is trying to get out in front of a general rejection of the fashion of his demolition man meme mobiles by giving no room for error from his engineers to make a mistake which will allow him to blame rhe ugliness on microscopic variations in plate size.
That’s an idea I would have supported when I was taking high school physics. My astronomy calculations I put to the nearest centimetre (something like 20 significant digits sometimes) for no good reason. Just writing down all the numbers from the calculator.
Then I took engineering and grew out of it. Sure some crucial parts need very tight tolerancing, but you also have to have it relative to the size of the part. And if your design is bad, better tolerancing isn’t going to save you from stuff like the steering wheel popping out.
He most certainly didn’t. Other than physical constants, very few measurements were ever taken to more than 15 significant figures. It’s just not practical as no instrument will get 1m precision over a light year. A spacecraft travelling anywhere near that far will just get an order of magnitude closer and then recalculate with one more digit of precision.
You are exactly right, and I wasn’t copy pasting I was writing it all down as part of pen-and-paper submitted answers. I don’t have 1/5 of the energy for such trivial things anymore.
My grandpa once published an article where he turned a tree circumference (obtained using a tape measure) into a “diameter estimate” with 6 significant figures. Turns out, he was wrong on the 4^th^ digit because he used π=3.14…
My high-school chemistry teacher would dock a point for each extra digit past the calculation’s actual precision. We learned quickly not to overstate our sig figs.
An answer written as “3” means that the true value is somewhere between 2½ and 3½. If you write “3.19142” when what you actually know is “3”, you’re incorrectly excluding the vast majority of the possible true values.
Our physics teacher taught measurements and uncertainties as the very first thing in our multi-year syllabus. All answers thereafter needed to be in the precision implied from the number of significant figures in the given figures and error propagation.
Yeah it’s one thing to spit out numbers. But as an engineer I have to understand what’s going to happen with thermal expansion, wear and tear, and what can actually be produced consistently by an apathetic worker on their 60th hour of work that week
Due to the nature of Cybertruck, which is made of bright metal with mostly straight edges, any dimensional variation shows up like a sore thumb.
It sounds to me like the reasonable conclusion to draw from this would be to modify the design of the car. I’d also assume you don’t need tolerances to be the same for literally all parts inside and out. I’d also think that, if the car looks that bad if things are 10 or more microns out of place, these cars are going to age terribly after regular use.
But what do I know? If I were smart, I’d be rich, right? And Elon is so rich, he must be a genius!
Oh yes, I’m all with you here, either make a frame and stick the “panels” to it individually (probably good if you make a cheap tank vehicle or something IDK) or make a chassis that take the deformation forces and distribute them as evenly as possible.
My bet is they have him as a stupid publicity monkey drawing attention to Tesla, cybortryck etc (I mean all publicity is good right?) and away from bad things like Tesla didnt self drive end 2019(?) and still doesn’t, child labour, … etc
I don’t have to be in the space program to know that Pluto is pretty far away and I don’t have to be a mechanical engineer to know the implementing exacting tolerances like this both in house and from external suppliers is going to drive costs through the roof just so his truck can look like a 90s wireframe model driving a literal information superhighway. With that being said, if you have better info I’d love to hear it. I just don’t think you do. I think you started with the assumption that Musk is some sort of gigagenius and then tried to make the inference from there that anything he says and does must be the right thing to say and do, and that anyone who criticizes him just isn’t following his hyperdimensional chess gambit.
Name one other auto industry CEO that makes engineering demands of this nature and lambasts employees on social media for not meeting them.
Without relying on Google etc. you probably couldn’t even name the CEO of Toyota, Honda, Ford, etc. And I seriously doubt they are making technical decisions for their cars. They rely on knowledgeable managers whose teams have decades of technical experience, and likely defer to those experts when they say something isn’t feasible.
Musk is acting like Homer Simpson when given the chance to design his own car. Screw the experts! He wants what he demands and won’t take “no” for an answer, no matter how bad his decisions are.
He’s been promising full self driving would be out of beta and readily available soon for over a decade now.
Cybertruck available in 2019.
one million Tesla robo-taxis by 2020.
Teslas will have a 600+ mile range very soon
And those are just some of his broken promises regarding Tesla, without even touching on widely held poor decisions like insisting on a “vision only” solution for full self driving, getting rid of the control stalks in the S and X in favor of touch controls on the wheel, etc.
And don’t get me started on the similar broken promises involving SpaceX, Twitter, Hyperloop, etc.
Yeah anything is possible with enough time and money, it’s just that is about the most textbook example of comparing apples to oranges I’ve seen IRL.
Also, I suppose Lego bricks might be considered low cost if you’re a billionaire, but in the grand scheme of molded plastics they are very much a premium product.
Well, of course. It doesn’t change my statement though.
And the guys down the lab could go “well, we don’t have to make it out of metal.” And then it starts a rabbit hole of further insane requests that are technically possible, but to people unfamiliar with engineering (Elon) say “damn the cost” betting (incorrectly) that the time or financial cost to fulfill the requests is still profitable.
Happens to a lot of products, unfortunately. People making demands are better off knowing what the demand entails. When they do not, this is what we get.
He’s also probably confusing his experience with Space-X too. He can’t think critically, and it’s going to be his undoing. I hope at least.
Maybe he can build the truck out of LEGOs - it would cost about a bajillion dollars to make something that size, but maybe less than the parts he’s demanding would be.
Try looking for Mould King or Cada - those are usually the ones that are considered to deliver great quality for a reasonable price.
It should be mentioned that both companies are gearing their products much more towards an older audience - so they aren’t really an alternative when talking about kids playsets.
I usually shop around on www.bluebrixx.com/en/ Their Specials didn’t disappoint so far. They carry other vendors too, but you might want to browse reviews on the web to see what’s really good. Quality does vary between vendors, but LEGO bricks aren’t as perfect as people believe either.
My kid got a non Lego set as a gift and what a letdown that was. It’s a frustrating excersise as the construction simply doesn’t holds up like the real thing.
Yeah, the tolerances are looser so it doesn’t click into place and stay in place easily. The plastic is less rigid and more pliable, making fitting even more difficult. The colors also fade more quickly.
I have a Mould King 13112 RC Excavator. All parts are on par and compatible with Lego bricks. Excellent quality, a bit tighter fit than regular Lego and the model itself is way more interesting and fun to build than anything Lego has produced in the Technic line in the past years. On top it is much cheaper than a comparable Lego set and it has an excellent building manual.
Apologies, I would recommend checking out www.bluebrixx.com/en/ to get an impression of what other vendors offer. You can look up the brands and models on your local Amazon, Alibaba, your local brick dealer, … These prices are a lot lower that LEGO sets, so you might be able to try different vendors and see what’s on the market.
I know, and I have loved Lego since getting that 8880 for Christmas that one year! But that is in the past, and spending 500€ on a LEGO set, when I can get a much more enjoyable experience from another vendor at a fraction of the cost, just doesn’t feel right to me these days. But to each their own, and I still love the LEGO sets I do have.
My homemade 3D printer that makes one of these rackus just because it’s not very good can make lego tolerance. It can’t cut metal though so I don’t know wtf he’s dreaming about lol.
Can I ask a question that may sound snarky and snobby over internet text, but I’m genuinely and non-judgmentally curious about?
Where did this use of “aesthetic” come from? From context it appears to mean something different in your sentence (good “look” or style that is on trend and I like) than I understood it to mean (“look” or style referring to an encompassing cohesion instead of a qualitative assessment).
This language enthusiast is curious. Language changes and that’s cool, but this seems to confuse the term rather than disambiguate. Can you explain what you mean by it, and do you remember where you learned to use the word that way? Is it a regionalism?
These tolerances are very possible to hold while machining, but speaking from my perspective having been a machinist by trade for 20+ years, holding those tolerances for every single part on a vehicle is going to get prohibitively expensive really fucking fast.
He’s probably hyper self conscious about people ripping into Teslas over their clearances (with inconsistencies measured in millimetres). But, no, instead of saying “VW can produce stuff that doesn’t look like it fell from a truck and you will figure it out, too” he’s going overboard.
If we’re going overboard, why bother with cars at all? Just use this cheesy blueprint, make it work and solve all of humanity’s problems! This is what California should invest in instead of trains.
Eh, if someone tells me to reduce a tolerance from 5 to 10 thou at work, it’s understood that it’s +/-5 and 10. I don’t think I’ve ever heard someone use the full range of a tolerance in conversation. If the tolerance isn’t bilateral, it would be said like plus 5, minus zero. Anyways, +/- .0005" is our standard tolerance on the span of all dowel hole pairs.
On the dowel hole point, just measuring this stuff is going to take at the bare minimum an automated and purpose built CMM, which will drive the cost up even more. If we are to assume +/- 5 microns for every single part - we are talking about the level of manufacturing that Mitutoyo or Starrett have. This will be a multi-million dollar vehicle that noone would buy.
Well, in terms of for real metrology, you are correct. A better comparison would have been Brown and Sharpe. However, Starrett has more than enough reputation of everything that they produce being of a very high standard- primarily layout tools like calipers, precision levels, etc.
ETA: This could very well be my bias as an American showing. I know from experience that the fit and finish of a high end pair of Mitutoyo calipers have what I consider to be subpar to the Starrett equivalent in terms of fit and finish. There is also a $500 ish price difference which could also be a subconscious bias.
Bilateral tolerancing is a Machinist’s first introduction to tolerancing so it’s no surprise to run that as default. And I suppose GD&T is not heavily used where you are.
If you’re given a parallelism tolerance of 10 micron are you assuming that to be ±10 micron? True position? Angularity of 5 thou? Etc… The only feature control that could be interpreted as bilateral by default is profile and it’s still communicated by its total tolerance.
Simple ± tolerancing isn’t the industry standard anymore. And if Tesla prints are anything like spaceX ones… It’s basically all GD&T and minimal title block tolerances.
I use GD&T on all my drawings, including 100% of my hole callouts. However I’m one of the more enthusiastic adopters of ASME Y14.5 at the place I work. Therefore, I get what your saying regarding the tolerance range, but since most of my coworkers are still relying on block tolerances, I’ll refer to a .010" positional tolerance as a “+/- .005” equivalent" in conversation so there is no miscommunication. I can see how this is not the norm.
I'm not even sure the Space Shuttle was built with those ridiculous tolerances. Maybe some internal engine parts like turbopump rotors and shafts. Does he know what he's saying?
10 micron (0.01mm) is pretty reasonable tolerance for a lot of stuff. The laminations in Tesla's motors will be held to somewhere around that, possibly even tighter. Things like motor winding insulation coatings will be far tighter.
For something like body panels or plastic interior pieces it's utter overkill and a waste of resources.
Something like a body panel is going to expand/contract a couple of orders of magnitude more than 10 microns just from the weather changing day-to-day.
It's pretty common for a CMM to be in its own climate controlled room. Parts will be placed in the room and allowed to reach reference temperature for a several hours prior to measurement.
On production lines you usually skip the absolute measurement of a CMM and use go/no-go gauges. One should fit, one should not. They'll be made of a material with similar thermal expansion coefficients as your parts. As long as they've both been sitting around for a while they'll be at the same temp. They'll have expanded or contracted the same amount from reference so their relationship of go/no-go will still hold true.
The whole field of metrology is a never ending rabbit hole - really interesting the more you get into it.
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