Bottas wheel nut still stuck on Mercedes car after pitstop issue

Mercedes will only be able to remove the wheel nut from Valtteri Bottas’s Formula 1 car upon returning to its factory after his race-ending pitstop issue in Monaco.

Bottas ran second through the opening stint of Sunday’s Monaco Grand Prix, sitting five seconds behind leader Max Verstappen when he came into the pits on Lap 30 to change tyres.

But Mercedes was unable to get the front-right tyre off Bottas’s car, leaving him stuck in the pits. Despite the team’s best efforts, it was forced to retire the car, bringing the Finnish driver’s day to an early end.

Mercedes technical director James Allison explained how the nut had become machined to the axle by the wheel gun, causing it to get stuck.

“If we don’t quite get the pitstop gun cleanly on the nut, then it can chip away at the driving faces of the nut,” Allison said.

“We call it machining the nut. It is a bit like when you take a Phillips head screwdriver, and you don’t get it squarely in the cross of the screwdriver.

“You start to round off the driving face of the screwdriver slots, and then you just simply can’t take the screw out of whatever it is you are trying to take it out of because you have no longer got the driving faces.

“A very similar thing happens with our pitstop nuts if the gun starts spinning and chipping off the driving faces of the wheel nut.

“Given the power of the gun, you can end up with no driving face and you just machine the nut down to a place where there is nothing left to grab a hold of, and that is what we had today.”

Allison revealed that Mercedes was unable to get the wheel nut off the car at all, requiring a high-power drill to make the removal back at the factory.

“We eventually didn’t get the wheel off, it is sat in our garage with the wheel still on it,” Allison said.

“It will have to be ground off, get a Dremel out and painfully slice through the remnants of the wheel nut. We will do that back at the factory.”

Read Also:

Bottas’s retirement cost Mercedes a likely podium finish in Monaco, allowing Red Bull to move into the lead of the constructors’ championship by one point after Lewis Hamilton could only finish seventh.

Mercedes team principal Toto Wolff said that there were “many factors” that contributed to the issue, refusing to put it down to a single error.

“We need to review the design, we need to review the material of our wheel nut, because the mechanics that operate the wheel nuts need to do it in a way that you can’t machine it off,” Wolff said.

“And as a matter of fact, a mechanic that did that is one of the best, and one of the fittest in terms of pitstop speed, that the team has.

“So there are always things coming together. It’s never someone’s fault, it’s always multi-faceted.”

Mercedes' wheel nut design

Wheel nut design on Valtteri Bottas' Mercedes F1 W12

Wheel nut design on Valtteri Bottas' Mercedes F1 W12

Photo by: Giorgio Piola

The wheel nut design on the Mercedes (pictured above) is not like those fitted on road cars.

Instead, it is custom built and is dome shaped. It features two vertical extensions that are captured by the wheel gun to rotate the nut on and off.

It was these extensions that were machined off during the Bottas stop and meant the gun had nothing to grab on to.

shares
comments

Related video

Leclerc driveshaft issue may be unrelated to Q3 crash - Ferrari
Previous article

Leclerc driveshaft issue may be unrelated to Q3 crash - Ferrari

Next article

The seven reasons why Monaco 2021 wasn’t a better F1 race

The seven reasons why Monaco 2021 wasn’t a better F1 race
Load comments
How getting sacked from Benetton made Mercedes' Allison Prime

How getting sacked from Benetton made Mercedes' Allison

He’s had a hand in world championship-winning Formula 1 cars for Benetton, Renault and Mercedes, and was also a cog in the Schumacher-Ferrari axis. Having recently ‘moved upstairs’ as Mercedes chief technical officer, James Allison tells Stuart Codling about his career path and why being axed by Benetton was one of the best things that ever happened to him.

Formula 1
Nov 28, 2021
The remarkable qualities that propelled Kubica’s F1 comeback Prime

The remarkable qualities that propelled Kubica’s F1 comeback

It’s easy to look at Robert Kubica’s second Formula 1 career and feel a sense of sadness that he didn’t reach the heights for which he seemed destined. But as Ben Anderson discovered, performance and results are almost meaningless in this context – something more fundamental and incredible happened…

Formula 1
Nov 27, 2021
The humbling changes Ricciardo made to deliver for McLaren Prime

The humbling changes Ricciardo made to deliver for McLaren

From being lapped by his own teammate in Monaco to winning at Monza, it’s been a tumultuous first season at McLaren for Daniel Ricciardo. But, as he tells STUART CODLING, there’s more to the story of his turnaround than having a lovely summer holiday during Formula 1's summer break...

Formula 1
Nov 26, 2021
The potential benefits of losing the F1 constructors' title Prime

The potential benefits of losing the F1 constructors' title

As the battle continues to rage over the F1 2021 drivers' championship, teams up and down the grid are turning their attentions to the prize money attributed to each position in the constructors' standings. But F1's sliding scale rules governing wind tunnel and CFD use will soften the blow for those who miss out on the top places

Formula 1
Nov 25, 2021
The invisible enemy that's made Hamilton's title charge tougher Prime

The invisible enemy that's made Hamilton's title charge tougher

After winning his past few Formula 1 titles as a canter, Lewis Hamilton currently trails Max Verstappen by eight points heading into the final double-header of 2021. Although Red Bull has been his biggest on-track challenge, Hamilton feels that he has just as much to grapple with away from the circuit

Formula 1
Nov 24, 2021
Why F1's inconvenient penalties have to stay Prime

Why F1's inconvenient penalties have to stay

OPINION: Quibbles over the length of time taken by Formula 1's stewards over decisions are entirely valid. But however inconvenient it is, there can be no questioning the importance of having clearly defined rules that everyone understands and can stick to. Recent events have shown that ambiguity could have big consequences

Formula 1
Nov 23, 2021
The mistakes Red Bull cannot afford to repeat in F1 2021's title fight climax Prime

The mistakes Red Bull cannot afford to repeat in F1 2021's title fight climax

OPINION: Red Bull has had Formula 1’s fastest package for most of 2021, but in several of the title run-in events it has wasted the RB16B’s potential. It cannot afford to do so again with Lewis Hamilton motoring back towards Max Verstappen in the drivers’ standings with two rounds remaining

Formula 1
Nov 23, 2021
Qatar Grand Prix driver ratings Prime

Qatar Grand Prix driver ratings

Qatar was a virtual unknown for most as Formula 1 made its inaugural visit to the Gulf state, and tyre management quickly emerged as an even more critical factor than normal. Perhaps then it should come as no surprise that two of the championship's elder statesmen produced standout drives

Formula 1
Nov 22, 2021