Mercedes McLaren SLR Production

Production of the Mercedes-Benz SLR McLaren at the McLaren Technology Centre in Woking, England, utlises both the advanced production systems of Mercedes and the sports car manufacturing expertise of McLaren.

Around 140 highly qualified staff manufacture up to 500 units of the Gran Turismo at the McLaren Technology Centre, McLaren’s HQ, each year. During the vehicle’s seven-year lifespan, the plant is intended to produce 3,500 cars. In total, the McLaren Technology Centre measures approximately 22,500 square metres, 4000 of which are utilised for SLR production. The centre also houses the Team McLaren Mercedes’ Formula 1 activities. Three of the seven production wings in the building complex are dedicated to the painting and final assembly of the SLR. The remaining four production wings are occupied by Team McLaren Mercedes Formula 1, McLaren Electronic Systems, McLaren Marketing and McLaren Applied Technologies.

The 460-kW/626-hp V8 engine comes from Mercedes-AMG GmbH in Affalterbach, while the specialists from McLaren Composites in Portsmouth deliver the carbon fiber body-in-white. The McLaren Technology Centre is the hub of production where all components are brought together and assembled and where final stages of production and testing take place.

The bodies-in-white are shipped to Woking from Portsmouth, around 100 km away. In the paint shop, which is located opposite the final assembly hall, the carbon fiber surface is painted by means of a special process. The final assembly of the SLR is mostly done by hand and takes place at nine stations along an 80m production line. Each step is carried out in keeping with the standards and processes of the ‘Mercedes-Benz Production System’, which was adapted to take into account the special circumstances of the SLR. Before moving on to the next station, each vehicle must pass a ‘quality gate’, to ensure high and consistent standards. Following

the assembly process, each vehicle undergoes a final test on the rolling test rig as well as driving tests used to fine-tune the chassis.



The production process for the SLR was thoroughly tested and optimized even before series production was launched. To prepare the employees for the special requirements associated with this particular series production run, the production technicians made the SLR prototypes as well.



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Mercedes McLaren SLR Production

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At the McLaren Technology Centre, advanced materials from the aerospace and F1 are used for the first time in the series production of the body and chassis. The SLR’s doors, bonnet and complete BIW are made from carbon-fibre composites (CFCs). Previously, CFC components were built by hand in a time-consuming process. In order to achieve a high degree of automation, McLaren worked with the Mercedes-Benz Technology Center in Sindelfingen to divide the production process into a ‘preform’ stage and a resin saturation stage followed by the hardening phase. Traditional textile processes such as stitching, knitting, weaving and braiding were adapted for the production of high-performance CFC fibers.



The longitudinal members of the front body structure consist of a central cross member and the encircling moulded part or internal web. The cross member comprises several layers of carbon fiber stitched together by a machine. After the form has been cut to shape, the web blank is inserted into a braided polystyrene core. This core element is then clamped into a specially developed braiding machine that produces the longitudinal member from 25,000 ultra-fine carbon filaments unwound simultaneously from 48 reels. This process allows the fibers to be braided around the core at a precisely defined angle to create the desired contour. Several layers are overlapped in certain areas, depending on the thickness required.



In an additional process, a computer-controlled tufting machine (as used in the textiles industry) joins the cross member to the braid of the longitudinal member. The braid core is removed and the preform of the longitudinal member is cut to the correct size. The preform is then injected with resin. A cycle time of just 12 minutes is required to manufacture the complex fiber structure of the longitudinal members using a braiding machine. This illustrates the potential production capacity that this innovative manufacturing technology offers for the future.



The rear shelf structure of the SLR further illustrates the new production techniques used for carbon-fibre processing. Despite being a very complex shape with several apertures, it is automatically manufactured as a single component. To achieve this, Mercedes-Benz and its partners adapted the Sheet Molding Compound (SMC) method to create ‘Advanced SMC’. The key advantage is that the carbon fibre mats are no longer manufactured by hand but by machine. Here, a handling system positions individual CFC layers at precalculated angles and in preset positions which correspond to the principal shape of the component, thereby creating the blank. Under heat this blank is then pressed, and in the process it takes on the precisely calculated form of the rear shelf. No subsequent reworking is therefore required

McLaren Composites also manufactures over 50 carbon fibre components for the car. The entire floor assembly, including all support members and securing elements, is made from one piece. The core of the carbon fibre composite roof frame structure (also manufactured as a single piece) is automatically filled with foam before the resin injection, creating a crash-resistant sandwich structure. High-strength bonding and riveting techniques ensure a reliable connection between the individual components of the chassis and the bodyshell. The aluminum engine mounts are bolted to the carbon fibre composite bulkhead and also bonded in place. The carbon structure includes integral mountings for the aluminum and steel rear axle.

Miscellany

Definitions

Designer or stylist? What’s the difference?

Terminology

Some of the vast car design jargon is explained here.

Car Design Terminology & Jargon

Car Design Definitions

What’s the Difference?

Car, automotive and transport design are virtually the same thing, with only slight differences existing between them. Automotive design usually, but not exclusively, refers to cars or automobiles but can incorporate any type of self-propelled vehicle (hence auto-motive). ‘Car design’ is self explanatory whilst ‘transport design’ tends to refer to a more general field incorporating types of vehicles – such as trucks or rolling stock (trains) – where perhaps more functional design is required

Designer or Stylist?

To some, there is very little difference between the terms ‘designer’ and ‘stylist’; to others though, the difference is enormous. Traditionally, a stylist is someone who is concerned solely with the visual appearance of a vehicle – how good it looks. Rarely though, do people nowadays have the opportunity to shy away from the genuine concerns about function and purpose that lie behind every aspect of a vehicle. To style an object or vehicle is one thing but you’ll only get points for something that can be used. Physical interfaces, such as handles and switches, are a great example of how functional items must tread the fine line between aesthetics and purpose. With an ageing clientele, brands like Mercedes-Benz will ensure that even their sportiest models have door handles that can be used by people with limited dexterity.

Useful Links

Legislation

One of the most significant issues affecting motor vehicle production is a vehicle’s ability to meet existing and future legislation. International vehicles such as the Ford Mondeo and Transit or the VW Passat will be designed to meet virtually all global laws whereas more regional vehicles, such as those for India or Russia, will often be designed to much lower legal specifications.



In this section we look at some of the key legislation affecting the majority of vehicles on our roads. We will also look more specifically at how the requirements in EU and US law vary.

Basic Considerations

Common principles in legislation, the basics that have to be considered first.

European Legislation

This section looks at those pieces of automotive legislation specific to the European Union. This is especially significant with respect to emmisions and recycling.

US Legislation

Looking at laws specifically for the US, it is also relevant for other countries in the Americas.

Disability Legislation

Something that has yet to take affect on the wider automotive industry, there are many considerations for vehicle design when considering users with disablities.

US Automotive Legislation

Within the United States, all new cars are subject to Federal Motor Vehicle Safety Standards (FMVSS). These are issued, amended and enforced by the National Highway Traffic Safety Administration (NHTSA). The first FMVSS was issued in 1967 and related to seat belts. Since then they have drafted legislation covering most aspects of vehicle manufacture, predominantly from a safety perspective.

Legislation governing fuel economy and emissions is jointly regulated by the NHTSA and Environment Protection Agency (EPA) through the Corporate Average Fuel Economy (CAFE) system.

The NHTSA administers the following laws relevant to automotive design:

Motor Vehicle Safety

Highway Safety

PART C – Information, Standards, and Requirements

All of these laws form part of the Title 49 US Code. They are documented in Subtitle VI – Motor Vehicle and Driver Programs, broken down as follows:

• Part A: General
  
  Chapter 301 Motor Vehicle Safety
  
  Chapter 303 National Driver Register
  
  Chapter 305 National Motor Vehicle Title Information System
  
  
  

• Part B: Commercial
  
  Chapter 311 Commercial Motor Vehicle Safety
  
  Chapter 313 Commercial Motor Vehicle Operators
  
  Chapter 315 Motor Carrier Safety
  
  Chapter 317 Participation in International Registration Plan and International Fuel Tax Agreement
  
  
  

• Part C: Information, Standards and Requirements
  
  
  
  Chapter 321 General
  
  Chapter 323 Consumer Information
  
  Chapter 325 Bumper Standards
  
  Chapter 327 Odeometers
  
  Chapter 329 Automobile Fuel Economy
  
  Chapter 331 Theft Prevention

Federal Motor Vehicle Safety Standards and Regulations

Useful Links

Legislation

One of the most significant issues affecting motor vehicle production is a vehicle’s ability to meet existing and future legislation. International vehicles such as the Ford Mondeo and Transit or the VW Passat will be designed to meet virtually all global laws whereas more regional vehicles, such as those for India or Russia, will often be designed to much lower legal specifications.



In this section we look at some of the key legislation affecting the majority of vehicles on our roads. We will also look more specifically at how the requirements in EU and US law vary.

Basic Considerations

Common principles in legislation, the basics that have to be considered first.

European Legislation

This section looks at those pieces of automotive legislation specific to the European Union. This is especially significant with respect to emmisions and recycling.

US Legislation

Looking at laws specifically for the US, it is also relevant for other countries in the Americas.

Disability Legislation

Something that has yet to take affect on the wider automotive industry, there are many considerations for vehicle design when considering users with disablities.

Useful Links

European Automotive Legislation

EC Directives Applying to Motor Vehicles