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This looks to me like a "cold shut", which is a type of casting defect.

"Cold shuts occur when two relatively cold streams of molten metal from different gates meet and do not fuse together properly during the casting process. This problem is visible to the naked eye – giving the appearance of a crack separating the two sections."

https://www.haworthcastings.co.uk/news/the-differences-betwe...

Cracks caused by impact have sharp edges and cracks caused by cold shuts have more rounded or sandy looking edges.



Is there a functional difference? Would cracks from a cold shut not disqualify the product (whatever it is) from going into service?


I think it’s safe to say cracks in a structural member are always bad. I think the point the OP is making is that it looks like a manufacturing defect not the result of a crash.


It's still a serious structural defect.

The importance of the distinction here is that Tesla can't argue the customer caused this...a cold shut can only happen at casting time.


Any sort of defect like this should disqualify the product. It’s embarrassing and alarming that this casting wasn’t scrapped.


It seems they have no automated optical inspection (AOI) system. Why? Theories. (1) Manufacturing site footprint availability. AOI on large assemblies with high throughput requirements may be extremely spatially and temporally inefficient as the need to control lighting means a substantial facility footprint may be required. (2) manufacturing operation build time pressures (3) assessments and claims by the casting equipment provider (4) the potential unavailability of an off the shelf solution suitable for parts of this scale.

Stable process control could eliminate the need, but AOI is relatively cheap insurance.


do you _really_ think this is a technical issue?


No it's clearly an alien conspiracy. You're right.


lol woosh




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