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The Smooth Ride
Ever since the invention of the wheel, man has searched for a
smoother ride. In the 8th century, iron chains suspended a riding
platform from the wheels. The swaying and rocking motion was so unstable
and it must have caused sea sickness! The clanking chains only made the
riding experience worse.
Superior technology wins wars. Mike Loades, a British expert in
ancient armor, has uncovered bits and pieces of an ancient British
chariot with an innovative suspension system. The platform rode on a
wooden arch suspended by “Y” leather straps. It was so stable a warrior
could launch arrows or javelins with deadly accuracy. This gave a
decided edge over the unstable and rough Roman and Greek chariots with
rigid axles.
A suspension system is nothing more than a means to keep the wheels
in firm contact with the road and give the passengers a smooth ride. All
types of springs, torsion bars, bushings, kingpins, and dampers have
been tried. Automobiles have swayed and bounced through many designs on
the road to today’s computer controlled ride.
Automobile inventions frequently arise from tragedy. Henry Leland
demanded an electric starter for his Cadillac after a back firing hand
crank killed a friend. Safety glass became standard after many maiming
lacerations. As cars gained weight and went faster, the early steering
and control systems proved inadequate.
William Brush took a curve too fast in his brother’s 1904 Crestmobile.
The right front wheel hit a rut and began a nasty shimmy. The elliptic
leaf spring and solid axle transmitted the force across the entire car
and he overturned in a cow pasture. Shaking off the grass, and who knows
what else, he muttered a desire for a more stable vehicle. Two years
later, his 1906 Brush Two-Seat Runabout sported a novel suspension
system with front coil springs AND a rudimentary shock absorber bolted
to a flexible hickory axle.

Brush used oil impregnated wooden axles on four coil springs to achieve
a smoother ride. The 10 hp car also had a brake pedal that released the
clutch when depressed and engaged it when it was released! That created
a “Whole lota’ of shakin’ going on!”
The coil spring had been patented in Britain fifty years earlier, but
was rarely used in automobiles. The leaf spring was a proven carry-over
from the wagon, and the metals of the 1900s were difficult to forge into
a consistent coil. A leaf spring attached easily and could be “beefed
up” by simply stacking more curved slats. While reliable, this
“sandwich” was bulky and squeaked incessantly. Some had rubber blocks –
early shock absorbers – on top to prevent it from striking the frame.
Since leaf springs were so common, the Leaf Spring Institute was formed
to maintain quality automotive standards. Henry Ford – always trying
something different – turned the leaf springs transversely in the 1908
Model T.
As cars became more sophisticated, owners demanded a smooth and safe
ride. Auto builders quickly scrapped the rigid front axle for an
independent front wheel suspension. Major changes swept the auto
industry during the mid-1930s. Cars now rode on front coil springs,
hydraulic shock absorbers, and improved bushings. The 1938 Buick floated
on rear coils as well. The 1935 Hudson touted “Axleflex” – a system of
“up and over” independent springing for each front wheel. Two years
earlier the Hudson had contracted with the now legendary Monroe company
to build the first original equipment tubular shock system.
Earlier in 1933, Czecho-Slovakian engineer Dr. Ferdinand Porsche
invented a torsion bar type spring that twisted a transverse steel rod
inside a tubular cross member. Each rod had a bell crank and steering
knuckle on the end. Another bell crank and shock absorber was above the
axle. That same year a German engineer offered a tubular frame with
truly independent suspension. The power axle flexed, similar to the
later VW swing axle. An obscure automobile, the 1907 Pilian, tried a
similar system using two universal joints at each end of the rear wheel
shafts. This system became very unstable over a bumpy road. When one
wheel momentarily left the road, the wheel camber changed abruptly.
Some type of shock absorber has been around since the infancy of the
motor car. One early designer simply crammed an inner tube in the leaf
springs! M. Houdaille, a French engineer, developed a hydraulic shock
absorber in 1908. His lever-action design cushioned many of the early
automobiles. The 1932 Packard had a unique Delco-Remy driver adjusted
system. A cable device on the dash changed the shock fluid level and
varied the ride firmness. Gradually, the piston shock absorber became
the industry standard. Jim O’Clair’s January 2005 article in Hemmings
Motor News is an excellent reference source for restoration of these
obsolete parts.
The control arm, so common in our AACA cars, has largely been
replaced by MacPherson struts and rack-and-pinion steering. MacPherson,
a General Motors engineer developed this compact system in the 1960s.
Now shocks hiss instead of drip as computer controlled airbags stabilize
most cars. Polyurethane and polygraphite bushings have replaced the
rubber. Everything is sealed – no more “grease jobs” with the oil
change! What will be next? Maybe we will be floating on magnets!
See you next month!
Bob
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