Unboxed Assembly
Assembly Line
🗜️ Tesla reinvents carmaking with quiet breakthrough
The company pioneered the use of huge presses with 6,000 to 9,000 tons of clamping pressure to mold the front and rear structures of its Model Y in a “gigacasting” process that slashed production costs and left rivals scrambling to catch up.
In a bid to extend its lead, Tesla is closing in on an innovation that would allow it to die cast nearly all the complex underbody of an EV in one piece, rather than about 400 parts in a conventional car, the people said. Two of the sources said Tesla’s previously unreported new design and manufacturing techniques meant the company could develop a car from the ground up in 18 to 24 months, while most rivals can currently take anywhere from three to four years. The five people said a single large frame - combining the front and rear sections with the middle underbody where the battery is housed - could be used in Tesla’s small EV which it aims to launch with a price tag of $25,000 by the middle of the decade.
Tesla turned to firms that make test molds out of industrial sand with 3D printers. Using a digital design file, printers known as binder jets deposit a liquid binding agent onto a thin layer of sand and gradually build a mold, layer by layer, that can die cast molten alloys. The aluminium alloys used to produce the castings behaved differently in sand and metal molds and often failed to meet Tesla’s criteria for crashworthiness and other attributes. The casting specialists overcame that by formulating special alloys, fine-tuning the molten alloy cooling process, and also coming up with an after-production heat treatment, three of the sources said. And once Tesla is happy with the prototype mold, it can then invest in a final metal one for mass production.
🚙🏭 Tesla Rethinks the Assembly Line
Engineers at Tesla Inc. have developed a new process that they claim will reduce EV production costs by 50 percent, while reducing factory space by 40 percent. The “unboxed” system was outlined during the automaker’s recent Investor Day event at its new factory in Austin, TX. Tesla believes that its more efficient production method will lead to a paradigm shift in the way that vehicles are mass-produced. It focuses on eliminating linear assembly lines and producing more subassemblies out of large castings.
“The traditional way of making a vehicle is to stamp it, build a body-in-white, paint it and do final assembly,” says Lars Moravy, vice president of vehicle engineering at Tesla. “These individual shops are dictated by the boundaries that exist in auto factories. If something goes wrong in final assembly, you block the whole line and you end up with buffering in between.”
“We simplified Model Y assembly with a structural battery, where the battery is [also] the floor,” says Moravy. “We put the front seats and the interior module on top of the battery pack, and we bring it up through a big open hole [in the bottom of the body]. This allows us to do things in parallel and reduce the final assembly line by about 10 percent.
“Unboxed assembly is also known as ‘delayed 3D,’” adds Mwangi. “In other words, you stay in 2D as much as possible and go to 3D as late as possible in the vehicle production process. That means you have open access to the majority of your work areas, which gives you an opportunity to simplify operations. It also lends itself to simpler automation, because robots don’t need to work around a shell.”