skateboard steering devices on the bottom of the board are called the
consist of a base plate (mounted to the base of the skateboard itself),
an axle which pivots on two urethane cushions (called bushings) and a
pivot point. This construction enables the wheels (which are attached
to the axles) to swing in a predefined arc, which allows the skateboard
design allows the skater to turn the board by leaning; lean right, the
board goes right. Lean left, and you go left. A nut called the kingpin
nut controls the ease of turning. Tightening this nut compresses the urethane
bushings, stiffening the action of the truck. Tightening the kingpin nut
makes the board more stable, but makes it much harder to turn. Loosen
it, and the board becomes floppier, but much easier to turn.
Vitello narrates a video tour of the Ermico
Foundry, where Independent Trucks and others are made. Molten
aluminum is poured into a steel mould, where it cools and hardens
around the truck axle. The truck is then removed, filed, polished,
and packaged as a finished product, ready to grind.
The most popular truck of all time, and the standard for the modern skater,
was the Independent Truck. As designed and produced by the combined creativity
of NHS and the Ermico Foundry, the Independent was a wonder of clean design:
smooth, easy turning, durable and strong. Fausto Vitello, one of the founders
of Ermico and one of the originators of the Independent Truck, described
the basic truck design: "The basic skateboard truck has not changed
in probably fifty or sixty years. It was designed around the 1920's for
ballroom roller-skate dancing,which had a big boom prior to the depression.
The basic system for allowing a truck to turn is called the Chicago pivot,
and all modern trucks are derived from that. What has changed in the Chicago
Pivot truck is that we have refined the system to allow better turning,
more stability, and certain other features that skaters demand."
Tim Piumarta agreed the skateboard truck has hardly changed at all over
the years. "Trucks have barely changed at all, in fact the skateboard
truck design and geometry was lovingly lifted from roller skate base plates
going back to the 1950's and before that. Two elastomers sandwiching a
yoke which was connected to an axle and everything pivoted on one point."