Post here all non technical related topics about Formula One. This includes race results, discussions, testing analysis etc. TV coverage and other personal questions should be in Off topic chat.
From McLaren F1 website because I can't link to it:
THE WHEEL RIM
A Formula 1 wheel is a piece of art, its flanks a blend of curves matched with a look of solidarity. Unlike many parts on a racing car, it’s relatively easy to understand the job done by a wheel, but the sort of wheel rims fitted to a Team McLaren Mercedes Formula 1 car are nothing like those on a typical road car.
Both are round, but there the similarities end. While weight on a road car wheel doesn’t make much of a difference, every single gram that can be saved on a Formula One car’s wheel is vital as strength and durability are balanced against lightness.
Each wheel is retained by a central wheel nut and receives its drive from the hub assembly via six drive pegs. There are 12 spokes, in six pairs, allowing hot air from the brakes to be ventilated through the wheel. Great gains have been made in this area over the days when cars ran with five solid spokes on the wheel rim.
The brake calliper sits within three or four millimetres of the inside of the rim, with the brake disc sited inside this. At the outside edge of the wheel rim, the surface has been shot-blasted to make it more abrasive at the point at which it meets the tyre bead so that they can grip better.
“The first thing that needs to be understood about a Formula 1 wheel is that there are dimensional requirement,” explains Head of Race Engineering Steve Hallam. “All wheels have to be 13 inches in diameter. A front wheel and tyre assembly has to lie between 305mm and 355mm. A rear wheel and tyre is 365 to 380mm. The diameter of a dry tyre can’t exceed 660mm, with a wet tyre allowed to be 10mm larger.”
There’s a further factor for the team to consider – the shape of Michelin’s new tyres for the season. Once this is known, the rim width can be finalised to bring the wheel and tyre within the rules. This is why a team’s wheels seldom arrive more than a few days before they need to be packed for transit to the opening grand prix.
Team McLaren Mercedes’ wheels are accurately machined from magnesium, a metal that’s chosen for its low density, by the Formula 1 team’s Official Supplier, Enkei.
Thoughts of using aluminium are dispelled, because, although it would be stronger, it would be too heavy. Carbon was once considered as a possible material, but this was banned, and all Formula 1 wheels must be metal under FIA regulations.
Monitoring the life of a wheel is vital, and this is why each of them is crack tested after 200km. It’s rare, though, that any wheel is used for more than 150km. Indeed, if a race is a two-stopper, they won’t do any more than 100km before being removed from the car.
Providing a wheel passes the crack test, its life could be as much as 3000km, but this depends, according to its weight and the material out of which it’s built.
Once again, radically different from the sort of life you would expect from a road car wheel rim, but this is just yet another reason why Formula 1 is such as fascinating and highly-specialised sport.
Technical Specification
Dimensions: Front 305-355mm; rear 365-380mm
Material: Magnesium
Number used per season: Up to 200 wheel rims are taken to each of the 16 grands prix in the Formula 1 season
this propertis r singnifiant but instead dilation and conduction of heat it`s very important. anyway i must to study about this subjest.. well the magnesium it`s ultra lights material.
For an unsprung component in a racing machine, less mass is paramount. It has a very direct influence on performance.
These wheels are built as light as possible, with many measures to ensure integrity. They are constantly tested by what is called "non-destructive testing" using such measures as X-rays, dyglo penetrant inspection, and ultrasonic methods. A suspect piece is rejected flat out.
As an example, in the last race of the 2004 NASCAR season, Kurt Busch (the points leader) had a wheel fail, and it almost cost him the title. This wheel was later found to have been used many times before, and fatigued.
So in serious racing, these wheels are constantly inspected for integrity, and even then, retired after a certain number of cycles, because the chance of failure carries tremendous risk. Not only safety, but the race results.
Dave totaly agree with u but in Formula1 they use the same rims for many times? i was thinking that after a weekend they change the rims, or maybe like u say they r constantly tested by "non-destructive testing" and ultra sonic methods. 10x
I have no idea how many times they will use a rim before it is retired. But I am willing to bet that for the last three races of the season, both Alonso and Kimi went out on rims that were brand new, each time.
There are testing methods to determine if a part is suspect. They also randomly choose rims and test them to destruction, and apply statistical analysis to guess how many times a rim is used before the odds start to look bad. But these are highly stressed, important parts of the car, and if a team used to be willing to use a qualifying engine, and a race engine each event, then it may be asumed they were willing to use new rims too.
All part of the huge budget in F1.
DaveKillens wrote:I have no idea how many times they will use a rim before it is retired. But I am willing to bet that for the last three races of the season, both Alonso and Kimi went out on rims that were brand new, each time...
Mclaren wrote:Monitoring the life of a wheel is vital, and this is why each of them is crack tested after 200km. It’s rare, though, that any wheel is used for more than 150km. Indeed, if a race is a two-stopper, they won’t do any more than 100km before being removed from the car.
Providing a wheel passes the crack test, its life could be as much as 3000km, but this depends, according to its weight and the material out of which it’s built.
I believe Magnesiun burns very well(white hot) when lit on fire. Its surprising that the amount of heat generated by the brakes does not set the rims on fire despite the tight fit between the two.
I have seen the brakes catching fire (BAR) but I cannot recall anyone burninng their magnesium wheels.
magnesium burns only if it's in a pure form. for the rims they use magnesium alloys - from what i've read somewhere else. don't know what are the other materials in those alloys. someone could help here.
they used magnesium for building F1 cars long time ago because it was light. but in case of an accident the car burned for sure.
When magnesium does burn, it is a wicked hot combustion. It's almost impossible to extinguish, and burns with a great amount of heat. But it's not that easy to get on fire, and as well, the rims sit out on the four corners of the car.
ranger wrote:is anyone talking about rims here? if not i'm not going to finish my post
1. Yes, all of the people are talking about rims.
2. Good!
...
Since 1955 and tragedy in Le Mans thickness of elements made of Magnesium must be at least 3mm by FIA regulations. Mercedes car that crashed and burned had bodywork made of thin Magnesium and it burned instantly. Magnesium alloy rims burn too. http://www.ewilkins.com/wilko/lemans.htm
FYI Water heaters have a rod of magnesium in the core, or at least used to.
When we were teens we extracted one, and cut off about 4 inches slowly with a hacksaw, that was 1.5 in diameter or so.
We threw it a in a fireplace, waited 30 minutes, and forgot about it.
A few minutes later, there was white light that made the rest of the log fire invisible, heat we felt from 15 feet away, and noise like an air hose blasting a puddle out of the way.
Before I do anything I ask myself “Would an idiot do that?” And if the answer is yes, I do not do that thing. - Dwight Schrute
if not i'm not going to finish my post
