moridin2002
Member
I think it's just the body in white (BIW) he thought was heavy. The thing is, if Tesla really does plan to re-use as much as possible from the 3 for the Y, it makes sense for them to standardize as much of the BIW as they can, which would mean at least some of it has to support both the 3 and the larger Y and will be a little stronger than it would if it was built just for the 3.
After watching the video, I'm kind of on the fence about Sandy. He's knowledgeable, but at the same time he tends to be a little critical of things he by his own admission doesn't understand the purpose of. It's probably just his background as a consultant and being used to questioning/being critical of things, but I wouldn't be surprised if Tesla had good reasons for what they did.
Take the upper a-arms. If Tesla's using a FRP/steel hybrid part, which is becoming fairly common in civil engineering, it could provide much better stiffness/strength to weight than a pure steel or Aluminum part, and if the FRP does fail, the steel core can hold everything together until it's fixed. I was wondering why Tesla wouldn't use it on other parts of the suspension, but this article suggests that hybrid parts can be adversely affected by exposure to water, especially salt water, so using hybrid parts in the lower suspension isn't a good idea.
https://pdfs.semanticscholar.org/9491/6d36ce588cf0edea05e38eb9bc02fa552ffa.pdf
But, Sandy’s experience doesnt exist in a vacuum. His company is taking apart, cataloging, and costing cars, planes, appliances, phones, etc... everyday. Assuming perfect decision making and execution on Tesla’s part is a dangerous road to go down.