Bottas finished second through the first stint of the Monaco Grand Prix on Sunday and was five seconds behind leader Max Verstappen when he pitted on lap 30 to change tires.
But Mercedes could not get the right front tire off the car from Bottas, so it got stuck in the pits. Despite the team’s best efforts, the car had to be abandoned, ending the Finnish Drivers Day prematurely.
Mercedes technical director James Allison explained how the nut was milled to the axle by the wheel cannon and it got stuck.
“If we don’t get the pitstop gun on the nut completely clean, it can chip off the nut’s drive surfaces,” Allison said.
“We call it the editing of the mother. It’s a bit like using a Phillips screwdriver and you don’t get it right into the screwdriver’s cross.
“You start to round off the driving surfaces of the screwdriver slots, and then you simply can’t take the screw out anymore because you no longer have the driving surfaces.
“A very similar thing happens to our pitstop nuts when the gun begins to spin and the wheel nut drive surfaces chipped.
“Given the power of the gun, you can end up with no face and just work the nut so that there’s nothing left to grasp, and we had that today.”
Allison revealed that Mercedes could not remove the wheel nut from the car at all and a heavy-duty drill was required to remove it at the factory.
“We didn’t get the bike after all, it’s still in our garage with the bike on,” Allison said.
“It has to be sanded down, taken out a Dremel and painfully cut through the remains of the wheel nut. We do that in the factory. “
Also read:
Bottas ‘resignation cost Mercedes a likely Monaco podium, which allowed Red Bull to move one point to the top of the constructors’ championship after Lewis Hamilton finished only seventh.
Mercedes team principal Toto Wolff said there were “many factors” that contributed to the problem and refused to attribute it to a single mistake.
“We have to check the design, we have to check the material of our wheel nuts because the mechanics who operate the wheel nuts have to do this in such a way that you cannot work them off,” said Wolff.
“In fact, a mechanic who did it is one of the best and, in terms of pit stop speed, one of the fittest the team has.
“Something always comes together. It’s never anyone’s fault, it’s always complex. “
Mercedes wheel nut design
Wheel nut design on the Mercedes F1 W12 by Valtteri Bottas
Photo by: Giorgio Piola
The design of the wheel nuts on the Mercedes (pictured above) is not like that of road vehicles.
Instead, it’s custom-made and dome-shaped. It has two vertical extensions that are gripped by the wheel gun to turn the nut on and off.
It was these extensions that were processed during the Bottas stop and meant that the weapon had nothing to grip.
The post Valtteri Bottas’ wheel nut is still stuck to the Mercedes F1 car first appeared on monter-une-startup.
