Mercedes has finally removed the wheel nut from Valtteri Bottas’ car, two days after it caused his retirement from the Monaco Grand Prix.
Bottas’ scheduled pit stop during last Sunday’s race saw him pull in from second place, however he was kept in his pit box when the front right tyre could not be removed.
Mercedes later discovered that the wheel nut machined onto the axle, which meant it couldn’t be removed.
The car was brought back to Brackley from Monaco, where it was removed at 9:59 AM on Tuesday morning.
Speaking in Mercedes’ post weekend F1 debrief, the team’s Motorsport Strategy Director James Vowles provided further insight into the failure.
“What happened is we came on slightly angled, so when the socket was now connected to the nut, it slightly angled relative to it and as a result of that, now instead of distributing the load across all of the nut it was across a small section and that tore the metal clean off and in fact all of the metal was now removed from the nut,” he said.
“As a result of that, the nut was in place and we were unable to remove it. That’s a brief overview of what happened. Clearly, it’s a circumstance that cost Valtteri dearly and cost the team dearly and one that we are going to put steps in place to mitigate.”
The DNF marked Bottas’ second non-finish in the opening five races of the 2021 F1 season, and he now currently sits 58 points behind championship leader Max Verstappen.
Vowles added that Mercedes understood in Monaco that it would take specialist equipment to remove the wheel nut, which gave it further time to understand what had happened.
“We did certain steps in Monaco to try and remove it, some during the pit stop, also some just afterwards,” Vowles said.
“Ultimately there we concluded that to remove that nut we were going to need some fairly heavy equipment and specialist equipment and that would be better done here in the factory.
“More so, it allows us an opportunity to do an autopsy on it to understand really how that nut was worn and gather some clues to allow us to do a better job going forward in the future.
“As a result of that we left the wheel on the car and packaged the car back into the truck to bring it back here directly.”
“What happened is we came on slightly angled, so when the socket was now connected to the nut, it slightly angled relative to it and as a result of that,…….
But the left wheel would have been just as angled and that side had no problem?
Yes multiple causes really, but underlying it is whether the margins/probability between a fast pitstop and machining off a wheel nut is perhaps too high? It’s a well-known issue by the commentary of David Coultard, etc but this is the first time I remember it being unrecoverable in the box.