Additive manufacturing, or 3D printing, has taken car manufacturing to a new level.
Three-dimensional printing, or additive manufacturing, promises us an unlimited supply of hard-to-build parts for our aging vehicles (it's the only way you'll find a clean gauge bezel for your Lamborghini Miura), and eventually the process will be used our modern vehicles too. Take GM and its Cadillac brand, who have been partnering with Carnegie Mellon University for the more than a decade on the technology. The group's latest venture brought us four complicated parts for the new Cadillac CT4-V and CT5-V Blackwing, but the more important piece, for now, is how it helps the manufacturing process. But first, we need to get our terms straight.
"3D printing is the building of a part, layer by layer, by a machine. Additive manufacturing is the entire ecosystem it takes to bring a product to industrialized fruition through 3D printing," said Brennon White, additive design and manufacturing application engineer for General Motors. "In order for us to do that, one of the first things in that ecosystem we need to think about is 'what is it built out of?' So the ecosystem encompasses many things, starting with new types of software and design paradigms. From there it goes into equipment and process development, to meet both repeatability and accuracy and throughput."
Sometimes they print the 3D part to net, its final form, engineers told us. Other times they print a part roughly, and then machine it to net after. That's where all the decisions come in, be it what materials need to be used, what speed it can be printed at, and how much the part or parts will cost to finish completely.
"But even with all of that together, you have to have a supply chain," said White. "It's not all done at General Motors. In fact, all the parts you'll see today are instead made at our supply base. We don't manufacture the production parts; everything starts with the applications. We start with understanding how to find the applications, then once we find the applications, we vet the applications."
The most important part is retraining designers and engineers to know when a part might be a good candidate for 3D printing. GM is currently doing presentations on this now. Its special operations group understands the technology and the logistics and is working to implement them wherever possible. But you need a network.
"It starts with universities and partners like CMU, and then it goes all the way out to the actual machine manufacturers. Are they doing the things in the future that we need them to do to support our future needs? And also our supply base. How do we get them up to speed? How do we help them understand what we understand," said White. "Oftentimes we'll get to a supplier and they'll say, 'I've never heard of printing metal,' and we say, 'well here you go.'"
Cadillac says that 3D printing is now coming out of the prototype phase and going into the production phase. It has labs working on new alloys and processes, and it even has a new facility and machine that engineers can be trained on to print their own parts. That's for when they get a little inspiration and need to play around, they can get parts in hours instead of days. But again, everyone needs to be educated on the value.
"Education is one of the most important parts, because people don't understand what's actually out there. You can teach one person, but we have 10,000 engineers. We're creating online training to get them up to speed. They need to be able to recognize a part that would work with additive manufacturing," said White.
The surprising part is that we're not just talking about parts that go on cars. The new Cadillac CT5-V Blackwing we just drove has four 3D-printed parts: an interior air vent, an underhood bracket, a wire harness and the medallion that goes on top of the Blackwing's shift knob. These parts were small enough and easy enough to create, and the production numbers on the Blackwing were small enough for it to make sense. But there are loads of applications in the industry, besides actual car parts.
There are parts to help with the building of parts like plastic jigs and hooks. GM can also make molds faster with 3D printing, which can then be used to make production parts. The key with both is the intricate designs you can create with the technology. The back side or b-side of a part can be made lighter, or it can be made to fit better. The company can put complicated cooling veins through intake heads that it could never get with forging. There aweight savings too, and the combination of two parts into one. The list goes on and on.
"We have 75 machines, but this additive industrialization center just came online during Covid. That is our commitment that we are making the move from just doing product development and manufacturing," said Blaine Heavener, global vehicle performance manager.
"There are really three different areas where this works," said White. "There's the production application that works because it's economical and it works because of the functionality it provides. Then there's the rear functionality that only additive can provide. I'd say today that's less than 5%. The real gold mine right now in automotive is the preproduction phase, which is where you're getting the development ready, accelerating it, and solving problems."
Say you have a problem where some part won't fit where it's supposed to go. And you already have ten ideas on how to solve it. That's when 3D printing comes in. It's where automakers can rapidly prototype and test before signing off on a couple hundred thousand widgets, or turbines, or whatever.
"In the past, you'd have to whittle it down to see which ones you could make in the timeframe. With additive manufacturing, I could make all 20 parts today. Once I have the CAD, I can do the production. I can do design experiments with real parts instead of the virtual world," said White.
"The other thing it saves is the tooling. We're able to wait on final designs because we can use additive to manufacture the tooling. Instead of tooling lead times that were 20, 30, 40 weeks, we can do that in much shorter times. We can shorten our development times," said Heavener. "But we need to change the mindset of the engineers. We need to make them aware of the opportunities."
And like everything else, these advancements are happening at a rapid pace. A decade ago, even five years ago, GM wouldn't have been able to do as much. It's a steep learning curve.
There was a 3D printed part Cadillac was trying to get on the Blackwing at the beginning, but the tech wasn't there. White told us if they started development today, that part could have been 3D printed. For confidentiality reasons, it wouldn't tell us which exact part. Regardless, it's all about speed. Not in the actual manufacturing, but in developing and helping along those processes.
"When AM is in your plant, you're able to execute within hours and days versus weeks to get the supplier in, design it, produce it, and then bring it back for manufacturing. So that's where we're using it today in a massive scale, in preproduction," said White.
But soon, with the right, small part that can be produced in batches, we'll be seeing 3D-printed parts all over our vehicles, in addition to already being all over the factory floor. And like we said at the top, if you need some weird old part for your prewar sedan, eventually this will be the only way to get it.