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By Christopher A. Sawyer, Contributing Editor
"The Monocage that we launched on the 720S is an
evolution of the Monocell concept introduced on
the original MP4-12C road car in 2011," says Adam
Thomson, Body Manager, McLaren Automotive
(see: adandp.media/articles/the-amazing-
mclaren-mp4-12c). Effectively a carbon fiber
bathtub that holds both the occupants and acts
as the primary vehicle structure, the Monocell
(or "Carbon MonoCell," as it was originally
called) is made in a single piece. When asked
how McLaren does this, the standard reply
is, "Very well, thank you," an answer very
much in keeping with the British company's
tight-lipped nature. However, a rigorous internet
search shows that production of the structure is
performed by Carbo Tech in Salzburg, Austria, using
bi-axial and tri-axial carbon fiber fabric produced by
Formax UK Ltd.
Further research shows that when McLaren intro-
duced its revolutionary center-seat, three-passenger
F1 supercar in 1992, it reportedly took 3,000 hours
to build its woven carbon fiber monocoque. By the
time the Mercedes-Benz SLR McLaren hit the market
in 2003, McLaren engineers
were able to reduce this time
to just 500 hours. The time
reduction was remarkable,
but still far short of what was
necessary for McLaren to
profitably produce a family
of high-performance mid-
engine cars. It used the next
eight years to whittle this
down to just four hours for
the MP4-12C.
Part of the time reduction
can be put down to process
improvements (production
time for each chassis type
dropped as familiarity with
the process increased),
but the greatest time savers were simplifying the
design of the structure itself and development of an
in-house process to model the bending and flexing
response of a material that, according to Thomson,
"has stiffness in one direction that is not necessarily
McLaren's Monocell
carbon fiber tub first
used on the MP4 12C,
and was the starting
point for all McLaren
road cars to follow.
Aluminum and/or
steel was used for the
upper structure until
the P1 hybrid super
car bonded a woven
carbon fiber roof
section to the tub to
create the Monocage.
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AD&P; ∕ OCTOBER 2017
CHASSIS