Being a fan of model cars and motorcycles I have a significant collection of ‘diecast’ toys, but it now seems that “Full Scale” diecasting is coming to Tesla!. I’m not sure how this would fit in my wall cabinet but certainly does seem Tesla is turning the tales on automotive production.
Tesla has made a significant breakthrough by combining multiple innovations that could revolutionize the way they manufacture electric vehicles and help Elon Musk achieve his goal of cutting production costs in half, according to five individuals familiar with the matter. The company introduced the use of massive presses with clamping pressures ranging from 6,000 to 9,000 tons to mold the front and rear structures of their Model Y using a process known as “gigacasting”. This breakthrough not only reduced production costs but also caused competitors to scramble to keep up.
In order to further solidify their lead in the market, Tesla is on the verge of another groundbreaking innovation that would allow them to die-cast nearly the entire complex underbody of an electric vehicle as a single piece, as opposed to using approximately 400 parts in a traditional car. This advancement is a crucial component of Tesla’s “unboxed” manufacturing strategy, which CEO Elon Musk revealed in March as a key factor in their plan to produce millions of more affordable electric vehicles in the next decade while remaining profitable. The exact nature and composition of these modular blocks, however, remains speculative.
Terry Woychowski, president of U.S. engineering company Caresoft Global and a former employee at GM, expressed his admiration for Tesla’s gigacasting innovation, stating, “It is an enabler on steroids. It has a huge implication for the industry, but it’s a very challenging task. Castings are very hard to do, especially the bigger and the more complicated.”
According to two sources, Tesla’s latest design and manufacturing techniques, which have not been previously reported, could enable the company to develop a car from scratch within 18 to 24 months, whereas competitors typically require three to four years. Furthermore, these individuals revealed that a single large frame, combining the front and rear sections with the middle underbody that houses the battery, could be utilized in Tesla’s upcoming smaller EV. The company aims to launch this vehicle in the mid-2020s with a price tag of $25,000. Read more about this here
Tesla is expected to make a decision on whether to proceed with die-casting the platform as a single piece as early as this month, although the final product may undergo changes during the design validation process. Neither Tesla nor Elon Musk responded to Reuters’ inquiries regarding this matter.
3D Printing and Sand: Gigacasting 2.0
Tesla’s breakthrough revolves around the design and testing of molds for producing large parts on a mass scale, as well as the incorporation of hollow subframes with internal ribs to reduce weight and enhance crash resistance. According to all five sources, these innovations involve the use of 3D printing and industrial sand and have been developed by specialists in design and casting from Britain, Germany, Japan, and the United States. The individuals speaking to Reuters requested anonymity due to lacking authorization to speak with the media about if or when diecasting is coming to Tesla.
However, automakers have been cautious about utilizing larger castings due to the challenges they present. Creating molds for parts measuring 1.5 square meters or more can improve efficiency but is costly and comes with numerous risks. For instance, making machining adjustments during the design process can cost up to $100,000, or completely remaking the mold may cost around $1.5 million. The overall design process for a large metal mold typically amounts to around $4 million.
Despite these obstacles, Tesla has remained committed to its vision of die-casting the underbody as a single piece. To overcome these challenges, Tesla turned to companies specializing in creating test molds using industrial sand and 3D printers. These binder jets printers deposit a liquid binding agent onto a thin layer of sand, gradually constructing a mold layer by layer that can be used to die-cast molten alloys. The design validation process for sand casting is significantly cheaper than that of metal prototypes and allows for easier adjustments and remakes. Companies such as Desktop Metal and ExOne provide the necessary machinery for these processes.
While the validation process for sand casting takes only two to three months, compared to six months to a year for metal mold prototypes, Tesla still had to conquer another major hurdle. The aluminum alloys used for the castings behaved differently in sand molds compared to metal molds, often failing to meet Tesla’s standards for crashworthiness and other attributes. However, the casting specialists managed to overcome this challenge by formulating special alloys, fine-tuning the cooling process for molten alloys, and implementing post-production heat treatments. Once Tesla is pleased with the prototype mold, they can proceed with investing in a final metal mold for mass production.
According to the sources, Tesla’s upcoming small car provides the perfect opportunity to cast an electric vehicle platform as a single piece. The simplicity of the underbody design in Tesla’s smaller vehicles, such as one intended for personal use and a robotaxi, eliminates the need for large front and rear overhangs due to the absence of a significant hood or rear trunk. As one individual explained, “It’s like a boat in a way, a battery tray with small wings attached to both ends. That would make sense to do in one piece.”
However, Tesla still needs to determine the type of gigapress they will use for casting the underbody as a single piece, as this choice will dictate the complexity of the car’s frame. In order to quickly produce such large body parts, Tesla will require larger gigapresses with clamping powers of 16,000 tons or more. This, of course, comes with a high price tag and may necessitate larger factory buildings. Several sources noted that high-pressure gigapresses cannot accommodate the 3D-printed sand cores necessary for creating hollow subframes, but Tesla can overcome this issue by using a different type of press that allows for slower alloy injection. This method produces higher-quality castings and can accommodate the sand cores, although it does require a longer process.
“Tesla could still choose high-pressure for productivity, or they could choose slow alloy injection for quality and versatility,” one source commented. “It’s still a coin toss at this point.” but what is for certain is that diecasting is coming to Tesla soon and it’s another big step from Tesla – The out of the box automaker.