Skateboarding. It's amazing where those wheels can take you. Into a "360," or balancing on a railing, 50 feet above the ground. But, for a few, it takes them deep in thought, in search of a better design. Talking with skateboard designer Tim Piumarta from NHS, Inc., Santa Cruz, CA, you realize it's much more than just a board and wheels. It's a high-level competition.
Skateboard designer Tim Piumarta.
The skateboard truck, defined by exploratorium.edu
as "consist(ing) 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," is vital to the success of the skateboard in its design. "You have to look at it from the curves going on," Piumarta says. "They also remind you of hand shaping in the early days of design, very round, original tooling, carved in wood by hand most of the time. When you're talking about a truck, you want to make sure it has strength, turn-ability, reliability, and consistency in design and in materials. You can't have a truck that lands a trick and lands in two."
As far as the wheels, there are two kinds. "Hard wheel, that's skateboarding for the park, street skating, doing an 'Ollie' slide down a hard rail launch off a set of stairs or out in a skateboard park," says Piumarta. "Soft wheel is categorized as just cruising. Just going down the street to the corner store or somewhere else."
Hard wheels on a skateboard enable one to do tricks like an ‘Ollie’.
The top level of both is achieved with a durometer. A skateboard wheel is placed to the bottom of this handheld device. "You put a skateboard wheel on a block (on a moving base) so, as you press rubber down, the wheel comes up and hits a point of a durometer," Piumarta says. "Then press it until it lifts four kgs into the air, which will tell you if it's too hard or too soft. To make the urethane for the surface of the wheel, you make sure there is no moisture in the mixing materials to get it to the right temperature in viscosity, then pump them in accurate meters to deliver certain grams into a cup … and make sure the ratio is right," he says.
When it comes to skateboard decks—what you put you're feet on—it starts with material from maple trees. "You boil it, bake it, dry it, and make veneer from it in cold or hot presses," says Piumarta. Do a CNC cut for male and female molds and squeeze the veneers and glues in the mold face. You can get 10 molds in each press and, depending on whether you're using a hot press or cold press, you press the rectangle and let it cure for a couple of weeks to get the moisture out of the maple. Then cut it with a CNC, though some use hand templates and shaper machines. Then after the shapes have been cut, bull nose the round of each edge. Trimmers cut the skateboard that way and then hand-sand it.
The truck provides the turning capabilities of the skateboard.
So now you know it's not just adding wheels to a board. But, even though it can be a lot of work and patience, Piumarta still loves the feel of being around the sport he loves and once was a professional athlete in. "Skateboards have been around for 40 or 50 years and I think people will keep on wanting to be a part of it," he says. "There will always be new people who want to discover how much fun it is."
Eric Butterman is an independent writer.
Skateboards have been around for 40 or 50 years and I think people will keep on wanting to be a part of it.
Tim Piumarta, skateboard designer, NHS, Inc.
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