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what's good and what's bad?

http://www.motortrend.com/news/tesla-model-3-teardown-deconstructed-3/

1. battery - best constructed in the business
2. body work - too heavy and too much reliance on "body glue"
3. electronics - best in the business - nearly space ship quality
4. panel gaps (January build) exceed industry standards
5. ventilation is innovative design

best electronics in the business - sub standard assembly practices lagging industry norms…
 

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Tesla's Simultaneous Brilliance And Incompetence Revealed In Teardown Of Model 3

Forbes report of the same TM3 teardown


  • "...sloppily joined together using a potpourri of robotic welding techniques, helping to explain the Model 3's ill-fitting body panels."

  • "A Tesla spokesperson said the primary car evaluated by Munro was built in 2017"

  • "There are other components that appear to the untrained eye to be jerry-rigged; A damper weight on a suspension control arm, for example, was secured using glue and industrial-strength zip ties."

  • "This car is the heaviest body-in-white I've ever seen," he said, calling the construction "ridiculous"

  • "...wheel wells are constructed of 9 different pieces of metal instead of one, as in most vehicles."
Everyone has an ax to grind. :(
 

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I find these two statement ironic:
1. battery - best constructed in the business
2. body work - too heavy and too much reliance on "body glue"

I have not seen the Model 3 battery, but the Model S battery module does use "glue" to keep the cells and the cooling strips together. Anyone can search the Web and find information on how these battery modules are built and later "disassembled" by those who buy used modules (from salvaged Model S) and selling the cells on eBay. I firmly suspect that Tesla (with Panasonic) is doing the same or similar for the Model 3 battery.

As for GM, search for the Weber Auto videos on YouTube where Professor John Kelly (while in a wheelchair!) actually disassembled and reassembled the Chevy Bolt EV battery almost completely by himself. There you can see who did a "better" battery construction.

Update: In the article I found this statement about the Model 3 battery:
"Each individual cell is glued to another and to the cooling channels." So the Model 3 battery modules are assembled in the same method with "glue" as the Model S modules. My suspicion was correct!
 

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Forbes report of the same TM3 teardown


  • "...sloppily joined together using a potpourri of robotic welding techniques, helping to explain the Model 3's ill-fitting body panels."

  • "A Tesla spokesperson said the primary car evaluated by Munro was built in 2017"

  • "There are other components that appear to the untrained eye to be jerry-rigged; A damper weight on a suspension control arm, for example, was secured using glue and industrial-strength zip ties."

  • "This car is the heaviest body-in-white I've ever seen," he said, calling the construction "ridiculous"

  • "...wheel wells are constructed of 9 different pieces of metal instead of one, as in most vehicles."
Everyone has an ax to grind. :(
The Forbes report seems to be adding nuance for effect IMO, as no one uses the term jerry-rigged to describe the suspension part on display. In the video, they note a metal piece attached to a control arm and guess that it might be a harmonic damper to absorb vibrations in the AWD version of the car. If you watch the video, Sandy repeats several times that he doesn’t know why certain things were done the way they were, and suggests that the types of things he is referring to only add unnecessary cost and weight. Tesla’s official response is that they stand behind the safety testing they have, and that the Model 3 design was taken from the Model S, which does have a very high safety standard rating. Tesla's response also goes on to say that occupant safety is number one and that it will be prioritized above all other metrics. Sandy also suggests that a lot of industry specialists, his company included, could help Tesla work through some of these problems. I think Tesla should take him up on his word, and listen to what he has to say. All they would have to lose in a short meeting is maybe a good pot of coffee. They likely have reasons for doing what ever it is they are doing, so they should be able to tell if any outside advice is worthwhile or not. Give the man a chance Elon! That being said, optimizing Model 3 body construction would put the Model 3 in a class by itself, and according to Sandy, other automakers have reason to be concerned.
 

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The Forbes report seems to be adding nuance for effect IMO, as no one uses the term jerry-rigged to describe the suspension part on display. In the video, they note a metal piece attached to a control arm and guess that it might be a harmonic damper to absorb vibrations in the AWD version of the car. If you watch the video, Sandy repeats several times that he doesn’t know why certain things were done the way they were, and suggests that the types of things he is referring to only add unnecessary cost and weight. Tesla’s official response is that they stand behind the safety testing they have, and that the Model 3 design was taken from the Model S, which does have a very high safety standard rating. Tesla's response also goes on to say that occupant safety is number one and that it will be prioritized above all other metrics. Sandy also suggests that a lot of industry specialists, his company included, could help Tesla work through some of these problems. I think Tesla should take him up on his word, and listen to what he has to say. All they would have to lose in a short meeting is maybe a good pot of coffee. They likely have reasons for doing what ever it is they are doing, so they should be able to tell if any outside advice is worthwhile or not. Give the man a chance Elon! That being said, optimizing Model 3 body construction would put the Model 3 in a class by itself, and according to Sandy, other automakers have reason to be concerned.
To piggyback on your post, here's the full Tesla response so Sandy does have their attention:
Tesla Responds

Statement on vehicle age
“The primary car evaluated by Munro was built in 2017. We have significantly refined our production processes since then, and while there’s always room for improvement, our data already shows that Model 3 quality is rapidly getting better.”
Statement on panel gaps and offsets
“Since we began shipping Model 3 last year, we have been very focused on refining and tuning both part and body manufacturing processes. The result being that the standard deviation of all gaps and offsets across the entire car has improved, on average, by nearly 40%, with particular gap improvements visible in the area of the trunk, rear lamps and rear quarter panel. Today, Model 3 panel gaps are competitive with Audi, BMW, and Mercedes models, but in the spirit of relentless improvement, we are working to make them even tighter.”
Statement on body weight/complexity
“The U.S. government found Model S and Model X to have the lowest probability of injury of any cars it had ever tested, and Model 3 was designed with the same commitment to safety. While there’s always room for refinement of cost and mass, which we are already improving, electric cars have unique safety requirements to prevent intrusion into the battery, and Model 3 was also designed to meet the latest small overlap front crash requirements that other reference vehicles may not have. We stand behind our physical crash testing and our computer simulations of it, which have been remarkably accurate, and the safety that they demonstrate. The safety of our customers is more important than any other metric.”


I too would like to see a more detailed rebuttal from Tesla of Munro's findings as he made a lot of suppositions admitting that he really didn't know why they did what they did, only that they could have done better. I have to think that the engineers they employ are pretty good at what they do and if there's a piece of steel or a 2 piece control arm, there's a good reason for it. But Tesla to their credit admits that they are constantly making improvements and won't stop till they've met their goals. I do get the feeling that Munro's baiting them to hire his firm to iron out the dinosaur technology aspect of Tesla's shortcomings.
All in all though, it was quite an about face from his initial video now that he's really sunk his teeth into the good bits. Not sure if the other guy McElroy will ever come around though. His snarky attitude was pretty thick and still is.
 

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"Each individual cell is glued to another and to the cooling channels." So the Model 3 battery modules are assembled in the same method with "glue" as the Model S modules. My suspicion was correct!
There's a HUGE difference between using glue for something like a body panel where the item is under stress (beyond gravity and inertial changes) all or part of the time the vehicle is in use and using glue in a battery pack which isn't really under any external stress unless you are in a major accident.

In the case of battery pack the glue can (and usually does) aid in thermal conductivity enhancing the effectiveness of the entire cooling system more than mechanical fasteners even when used with heat-conducting compounds (thermal paste).

As a car company Tesla has many many issues to work out but by every expert account I've ever seen or heard of their battery packs are state of the art.

IMO if you're going to grade mass-market EV battery pack sophistication and expected longevity you put the Leaf at 1 and the Tesla Model S at a 10 the Bolt is probably a 6 or 7 based on the Weber Auto teardown.
 

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Autoline After Hours complete Model 3 teardown

Forbes report of the same TM3 teardown


  • "...sloppily joined together using a potpourri of robotic welding techniques, helping to explain the Model 3's ill-fitting body panels."
  • "A Tesla spokesperson said the primary car evaluated by Munro was built in 2017"
  • "There are other components that appear to the untrained eye to be jerry-rigged; A damper weight on a suspension control arm, for example, was secured using glue and industrial-strength zip ties."
  • "This car is the heaviest body-in-white I've ever seen," he said, calling the construction "ridiculous"
  • "...wheel wells are constructed of 9 different pieces of metal instead of one, as in most vehicles."
Everyone has an ax to grind. :(
If you watch Sandy Munro's report on Autoline After Hours - (You Tube); you'll see that he definitely did NOT have an axe to grind and to suggest that he did is extremely unfair.



https://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=1&cad=rja&uact=8&ved=0ahUKEwjwhYXJ7pnbAhXrt1kKHVGsBWsQtwIIJzAA&url=https://www.youtube.com/watch?v=CpCrkO1x-Qo&usg=AOvVaw0A2vBS-UZFM7hpVOotabqz




His business is about making money from automobile costing ... essentially to understand both the product and the processes that make a particular car what it is. Not surprisingly, the Chinese are his biggest customers because they want to reverse engineer (everything).
 
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