It is evident mega castings gave Sandy Munro hope. He really thought that Tesla would use that solution to bring an end to the puzzle the rear structure of the Model 3 was. His disappointment is evident when he realizes that the 2021 electric sedan has just minor improvements when mega castings could solve its panel gap issues.
According to Munro, such a large quantity of pieces to make the rear structure in the Model 3 is probably the cause for the defective body geometry. When you put so many of them together by welding, the process tends to creep them. If one side of the rear structure has one size and the other has another one, it will be hard to get panel gaps right.
An irregular body structure also puts elements such as the glasses under stress. That could explain why the Model 3 has some glass-shattering episodes. The ones trying to exempt Tesla from responsibility claim temperature changes cause the stress that leads to the issue. What if it is caused by the body geometry, especially considering Tesla’s have no window frames? In that case, the Model Y would not have the issue – sadly, it does.
Munro asks “why” Tesla has not given the Model 3 the mega castings the Model Y has multiple times. One of the reasons he comes up with is that this could be “bean counters” fault. In other words, someone at the financial department claiming that new tools for a similar structure on the Model 3 would cost a lot and that the current tooling they have for all these body panels still needs to be amortized.
Another reason for avoiding the change could be Tesla’s production capacity for mega castings. The current machines may only produce enough of them to the Model Y. Would there be room for another of these die-casting machines in Fremont?
Whatever the reason is, Munro tries to see the bright side of the situation and shows some improvements in the car construction, such as fewer welds and rivets. However, that barely helps conceal Munro’s disappointment. In his words, he has no idea who designed the Model 3 rear structure, but he “can’t say enough bad about them.”
At this point, we have no idea if the Model 3 will ever have the improved body structure the Model Y presents. If it ever does, it will probably come out of Giga Berlin or Giga Austin.