A 16,000 Ton Press

Huge news has reached the Tesla community by way of a September 14th article by Reuters. 5 anonymous sources close to recent company projects say that Tesla has made a major breakthrough with their GigaPress technology - a breakthrough that could change everything about how the company manufactures their vehicles.

Currently,  Tesla uses their gigapress casting machines to simplify the production of the Model 3, Model Y, and the new Cybertruck. This is done by casting large portions of the vehicles' underbody in enormously powerful presses - eliminating a process that normally requires many parts to be welded together. 

This has saved Tesla as much as a reported 40% of manufacturing costs with just the Model Y alone, as they have replaced about 70 parts with two large castings and a structural battery pack.

It was no surprise then, to learn that Tesla is looking to repeat this efficiency with their upcoming 25 thousand dollar vehicle platform - a more compact design that Tesla intends to leverage for both an affordable EV, and a new take on the Robotaxi.

This is the vehicle that was teased during Tesla’s Investor Day Event on March 1st, alongside a lengthy presentation on the company's new approach to manufacturing.

This "unboxed method" of production would innovate the standard way of assembling a car - a process that hasn't seen much updating over the course of the last hundred years or so. 

The idea was for various sub-assemblies of a vehicle to be put together at different stations simultaneously - allowing workers to more easily reach parts, and work alongside robots with less difficulty. Current car assembly is very linear, with vehicles moving from station to station while getting parts attached in a specific order - which often leads to some awkward working environments as the vehicle gets more complete.

In this proposed new system, all the pieces would come together at the end - the whole process saving time and money by efficiently spreading the work around.

However, as the Reuters sources tell it, some new technology - as well as the lessons learned during Cybertruck’s production - has allowed Tesla to think bigger - much bigger. It looks like they want to cast the whole underbody for this new vehicle in one piece.

First off, the team learned a great deal about casting larger pieces with the Cybertruck. The parts for this vehicle were so much larger than their previous work with the Models 3 and Y, that Tesla was forced to get two new GigaPress machines with a pressure rating of 9,000 tonnes of force.

But this new vehicle is going to be smaller than even the Model 3 - with the sources explaining that the new vehicle’s current design has a very small front and rear - almost no storage space at all. A perfect test subject for testing this one-piece underbody casting idea.

However, it's not like Tesla’s 9000 tonne presses could handle an entire underbody, even if the new vehicle is very small - so they need a bigger press.

About 16,000 tonnes if the sources are to be believed - and a press that big runs across a few problems, not least of which would be that their size alone would probably mean redesigning the buildings they go into. But that's actually not the biggest problem either.

Making moulds for casting machines is expensive - even on a small scale. This makes it especially difficult when designing a vehicle for a casting system, as changes to the moulds can run anywhere from hundreds of thousands of dollars, to millions depending on the size. And here is where the new technology comes in.

Tesla needs to be able to have test moulds that are cheap to create, so that they can freely play with the new vehicle’s design during pre-production. They also need to be able to make moulds that incorporate hollows - something that cuts down on weight and increases a vehicle’s safety during a crash. That’s hard to accomplish with a normal casting mould.

So Tesla is going to use sand.

No, really - sand is going to reportedly be a huge part of the new process. Some new developments from casting specialists in Europe, Japan, and the United States have figured out how to effectively 3D print intricate and detailed structures with industrial sand - a high-silica content sand that’s normally used in things like glass-making, insulation, and several other construction-related processes. Here’s how it works for the moulds:

As the large printer arms lay down layers of sand, they mix in a binding agent to give the structure some stability. Industrial Sand is a widely used material, so it’s fairly easy to work with and it can form complex shapes with intricate details - and it’s easily reusable. This means that new moulds can be quickly made, discarded, and repurposed in order to design finished moulds that can later be made in metal - for as little as 3 percent the cost of traditional mould-making techniques, and less than half the time!

Add to that the ability to form hollows in a mould by adding 3D printed sand-cores - which can be easily removed afterwards.

However, there are a couple of problems that still need to be figured out.

For instance, the sand-cores reportedly can’t be used at the proposed 16,000 tonne pressures that would be needed to cast a single body in the method that Tesla has been using. They could switch to using injection mould techniques - slowly injecting molten material into the mould chamber instead of a high-pressure squeeze. This would make a higher-quality cast which could use the sand-cores… but it’s slower.

But this is all part of the process when picking out a new production system. Tesla will be making efficiency gains in some areas so that they can hopefully make speed and quality gains in others - it will be a balancing act.

One thing is for sure though: if Tesla can pull this off, they’ll be revolutionising the way cars are built, and proving what can be done with the careful application of new technologies.