The Formula One car up close - wheel nuts 27 Nov 2003
The humble wheel nut may not be the most glamorous of a Formula One car's components, but it still needs to be engineered perfectly if costly pit-stop errors are to be avoided.
Unlike the majority of a Formula One car's parts, the manufacture of the wheel nut does not have to be a particularly scientific process. Machined in conventional fashion from a block of steel, Jordan have used the same simple nut design since 1997.
"A lot of the other teams seem to use these new ones that don't tend to look like wheel nuts at all," explains Jordan's chief mechanic Andrew Stevenson. "They've got all these special sockets and odd-looking fins on them, and are supposed to be more efficient for pit stops. We actually tried them, but found they didn't make any difference to us at all - apart from the fact they were 10 times more expensive."
Be it Jordan's retro classics, or the more bizarre-looking high-tech designs, a set of Formula One wheel nuts weighs around a kilogram. Jordan pay around US$60 for each nut and will get through around 250 per season. Their life expectancy does, however, vary.
"We'll always start a session with a new set, but once we get back to the factory after a race all the wheel nuts that still look to be in working order are crack-tested," says Stevenson. "If nothing is wrong with one, it'll be used in testing."
Arguably the biggest enemy of the wheel nut is the pneumatic air gun used at pit stops. The gun will often bend a nut out of shape, rendering it useless. As for the dreaded prospect of cross-threading? "We have a special thread," admits Stevenson, "but it's a trade secret..."
(The above is an edited extract from a much longer feature on the minutiae of the Formula One car, which also includes looks at the cooling fan and the fuel tank. It is available exclusively in the December issue of Formula 1 Magazine.)