Page 63 - SAEINDIA Magazine December 2020

LIGHTWEIGHT

Feature

Sandy Munro, CEO at Munro & Associates, the
benchmarking and competitive analysis firm renowned
for its highly analytic “teardowns” of popular and
innovative vehicles, recently completed a teardown of
a Model Y. A series of internet videos covering Munro’s
assessment garnered more than 36 million impressions
in little more than a month. Munro was particularly
impressed by the current two-piece aluminum underbody
structure – and openly offered admiration in an interview
Area of the Model Y’s
with SAE’s Automotive Engineering. body structure that soon will be
encompassed by a single cast component.
He said the current Tesla Model Y has “two of the biggest
castings we’ve ever seen in a car. We’ve never seen them The mammoth machine is being supplied by IDRA Group,
used in an automobile before of that size. There are lots an Italian leader in HPDC equipment founded in 1946.
[of innovative aluminum applications] at Cadillac, BMW, Tesla is the first customer for IDRA’s hulking OL6100
Audi – they’ve all used castings. But nothing quite the CS (with upgraded locking force to handle the special
size of this thing.” Tesla casting), destined for installation in the company’s

Munro also participated in the podcast in which Musk Fremont, California, and Shanghai, China, plants. IDRA’s
spoke of the coming single-piece casting. Moving to the “Giga Press” measures some 64 feet (19.5 m) long and 17
“mega casting,” as Munro dubbed it, “definitely wins feet (5.3 m) tall. Along with the higher clamping force is a
the prize,” he asserted. “That’s going to be the biggest maximum aluminum-alloy “shot” weight of 104.6 kg (231
casting for quite a while. Nobody’s exploring that.” lb). The OL6100’s output may be lightweight castings, but
the machine itself is anything but light, weighing more
It happens to “require the world’s biggest casting than 410 tons.
machine, which we have two of. It’s the size of a small
house, basically,” gushed Musk. “It has a big effect on the The single-piece casting for Model Y will replace around
ease of manufacturing.” 70 stampings, extrusions and castings that currently
make up the same fabricated
assembly in the Model 3, on which
much of the Model Y is based. Musk
described the Model 3’s rear structure
as “a patchwork quilt – it’s not great.
The complexity in the body shop is
insane,” he said.
Harbour agreed. With such a large
and inclusive casting, “Even with
a big cycle time, you eliminate all
the labor to assemble pieces and
subcomponents,” she observed.
“You’re saving on automation cells,
you’re saving on people. It would be
tough to put dollars to it, but think of
multiple suppliers doing stampings,
you could save maybe 20% on labor
cost. And the reduction in footprint is
major. My guess is that it’s a net-net
efficiency gain.”
One side of the current Model Y’s two-piece rear-underbody aluminum casting.

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