Unlike the first engine and chassis builders, who had no precedents to
follow, the first auto body engineers represented an old established craft. It
mattered little to them whether vehicles were to be propelled by a gasoline
engine, electric power, or steam. Their task was the same as in the days of
chariots: to construct a conveyance that would carry people.
The body builders contended that if carriages were good enough for horses,
they were good enough for engines. They were even given carriage names
-- phaeton, brougham, tonneau, landaulet, and wagonette.
Don't get the idea that early body engineers were a stodgy conservative
bunch. When it came to trying new structural concepts and materials, they
were as radical as the engine and chassis guys -- so much so, in fact, that
practically every body structural technique in use today had been tried by
1920, even gluing bodies together.
In 1984 Volvo announced the use of epoxy to tack-weld body parts
together, thus reducing the number of conventional spot welds from 4000
to 500. But Volvo is not No. 1 in the use of glue for this purpose. Body
engineers used casein to hold early wooden body members together on the
Cadillac, Columbia, Locomobile, and Peerless of 1898 to 1904 among
others.
If we had to pick the two most revolutionary events in the development of
the auto body, we would select the transition from wood to metal and the
development of quick-drying lacquer -- events that occurred 25 years
apart.
The wooden body panels of those early cars restricted body designers.
Wood can only be steamed and bent into simple curves. When applied to
wooden frames, the body panels of one make of car looked pretty much
like those of any other make.
When sheet steel and aluminum came along in 1900, this sameness in
appearance started to change. New metalworking techniques were perfected
-- drop-hammering and power-hammering in the 1900 to 1910 era,
hydraulic stretching around 1920, and drawing and stamping around 1935.
As each occurred, metal panels began taking on new, novel shapes. The
first U.S.-built auto to sport a steel body was the 1901 Eastman Steamer,
the first to have an aluminum body was the 1902 Marmon. Both were built
with all-wood frames to which metal panels were pinned.
The wood frame/metal panel arrangement lasted about 10 years. Then,
wood frames reinforced with steel to give the car body greater rigidity
came along. Called armored wood, it saw its first use as framing to hold
the steel body panels of the 1911 Hupmobile. Built by Edward Budd, the
Hupp body was the traditional design for the day -- a touring (open)
car.
Closed cars were available from about 1900 on, but they found few takers
since they cost about 20 percent more than open vehicles. To protect
passengers in open vehicles, several automobile accessory companies made
lots of money selling folding, cape and canopy tops.
The closed car, or sedan, became less expensive and more attractive soon
after World War I thanks to Budd, who devised ways to cut the
manufacturing cost. In 1919, Dodge brought out the first closed car with
steel frame members and body panels.
The development of quick-drying lacquer that could be sprayed on
occurred in 1924. It, more than any other development, ushered in the era
of mass auto production. Until then most auto bodies were finished with
paint and varnish, which took weeks to dry. Some old timers remember the
days when new cars were lined up for miles along Detroit's Woodward
Avenue waiting for "that damn varnish to lose its tackiness." Meanwhile,
the production lines slowed to a crawl. There was just no more room to put
cars.
Lacquer cut the drying time first to days -- then to hours. Developed by
Duco, its first use was on the 1924 Oakland. Oakland was the original
division of General Motors that later became Pontiac.
On a late October afternoon in Detroit in 1915, an auto body engineer by
the name of H. Jay Hayes was presenting a talk before the annual
conference of the Society of Automobile Engineers. Hayes represented the
Ruler Auto Co., and recounted in rather humdrum fashion the development
of the auto body.
During a pause in his speech, a voice boomed, "What do you think about
the moot theory of combining the body and frame into one unit?"
The voice got attention of everyone in the audience. They waited with
interest to hear Hayes' response. The combined body-frame theory had
been bandied about for almost 10 years, but no car company had developed
a cost-effective way to turn theory into reality.
Hayes presented a 15-minute dissertation on the virtues of unitized body
construction -- what we call today unibody or unit body construction. He
explained to his fellow engineers how, by making the car smaller and
lighter, it was possible to overcome the two main disadvantages of
combined body and frame construction: excessive cost and body
vibration.
Hayes then dropped a bomb by announcing that the following week his
company was going to put on sale 3000 vehicles with unitized bodies. The
car was called the Ruler Frameless.
As Hayes had promised, the vehicles appeared on the market without
framing. Instead, body members were fashioned into tubular form to give
metal the rigidity it needed to do without a frame. The engine and
suspension members rested on a platform.
Here are some highlights in body evolution:
Books on automobiles
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