3D printing is becoming more useful for making production parts for cars, as seen but the use of 3D-printed control arms on the upcoming Ferrari F80 supercar. But the technology plays an important role in making large-scale castings practical for mass production.

That’s according to Jon Walker, key account manager at EOS, a leader in manufacturing and 3D printing. He says that the automotive industry’s interest in large-scale castings and its interest in 3DP is similar. “It aligns with the stuff we talk about in 3DP, which is part consolidation,” he said. “You have something that had to be four or five separate tools or four or five separate parts to be welded and finished and consolidate it to one.”

While the two manufacturing techniques might sometimes be positioned as competitors, 3DP supports large-scale castings because of the need for inserts in the casting die that create the right shape.

“I have seen pictures of die-casting tools where you can walk through them,” said Walker. “It is like standing in the jaws of a megalodon in the museum to show how big the shark is!”

The parts that come out of such huge dies are equally impressive. “Think how much time it saves, making one large tool and reducing downstream assembly,” he said. “It can just go to the next step faster. There is much less finishing work involved.  Those are huge quantifiable savings. Any time you can take something that was three components or six or ten and get it down to one monolithic part, you do it.”

Related:Why the Auto Industry is Following Tesla’s Lead into Large-Scale Castings

Of course, if it was easy to do this, large-scale, high-pressure die casting would have happened a lot sooner. “Bigger tools create new challenges,” Walker observed. “New challenges create the opportunity to use 3DP inserts.”

These inserts shape the resulting part, letting carmakers pinpoint some part of the tool where the shape needs to be refined. They also provide a better ability to control the thermal characteristics of the tool.

Of course, huge casting dies require huge die-casting machines, and those are hard to come by. “There are literally a handful of those machines,” said Walker. But over time, more of them will be built, so more manufacturers will have to wrestle with the challenges of using them.

“The bigger, more complex something is, the more likely it is to fail,” he explained. “The end-use part is heating and cooling at different rates. “One corner might be hot while one corner is still cool.”

Carmakers can plan to accommodate this by doing modeling and analysis, so they know where the hotspots are and can take steps to cool them. “There is great software that can do modeling and analysis,” Walker said.

Related:Tesla's Switch to Giga Press Die Castings for Model 3 Eliminates 370 Parts

Once the parts are cast and built into cars, then other issues arise that will have to be addressed as large-scale castings become more commonplace. “If you have a crash that is one step worse than a fender bender, you have to scrap your car. That’s crazy,” he concluded.