I've decided to start a new series highlighting how different super cars are built, called "Inside the stable". This weeks feature is the Wiesmann MF5 GT. Wiesmann is a boutique automaker headquartered in northwest Germany. Brothers Martin and Friedhelm Wiesmann founded the company in 1985, and set out making one of a kind hand built super cars.
Customers are able to watch their Wiesmann as it goes though any stage of the production process. The MF5 is constructed of an all aluminum monocoque chassis, consisting of only 111 parts.
The chassis is then dipped in cathode paint and bonded with stainless steel rivets and polyurethane adhesive. The engineer applies a reactive adhesive around the entire chassis. Then an adhesive designed to glue together metallic parts is applied which requires curing for 24 hours at 70 degrees Fahrenheit.
In a different section of the factory, fiberglass parts like the engine cover are built. A technician uses a paint roller to apply a layer of gel coat, which is a hard polyester resin coating, when used to provide a smooth glossy protective surface. Using a wet film thickness gauge the specialist measures the gel coat in microns for meticulousness. Another engineer uses a foam paint roller to cover the non-woven fiberglass layer in 2-3 coats of polyester resin. The engine cover is made from 5 different layers of fiberglass. An engineer then inspects it for accuracy. The dashboard is also made of fiberglass. Using a variety of hole cutting saws, an engineer then makes holes in the dash panel for the speedometer, odometer, push start function as well as the radio and AC controls.
Crucial to the rear body shell, is the mold, which is made of fiberglass. The rear body shell weighs about 440lbs, and takes 2 weeks to construct.
In another area of the workshop, the production of a windscreen for a convertible is being constructed. Two engineers place a strip of foam material wrapped in 2 layers of fiberglass into the mold, and then a technician lays down bonding glue between the foam and the windscreen mold. The workers lay down a matching component onto the fiberglass mold and add pressure to set the piece in place. Engineers then position “F” clamps to hold the composite mold in place. The windshield mold remains stationary as it cures for 24 hours at room temperature, before a heat curing treatment.
At the factory paint shop, engineers grind and sand the front body shell in preparation for fresh paint. In the next room the painter lays down the first layers of paint, while another sands and polishes the surface.
Made by hand which run throughout the car are the wire harnesses. The wire harnesses are used to relay signals or electrical power throughout the car, such as starting the engine or turning on lights, this process takes 4 days. The Wiesmann MF5 is composed of 587 wires with a total length of 3800ft.
In the upholstery section 4000 interior combinations are available for potential customers to choose from. Then an engineer places a thin cardboard piece is used to cut away the unused portions to ensure all of it is used and none is wasted.
Certain sections of the leather are placed under a stamp machine to place the company emblem on the seats. A seamstress sews pieces together double stitched and padded or quilted to match client desire. Wiesmann offers 400 types of leather to choose from. Another engineer sprays the interior frame pieces with adhesive to place leather on its corresponding section. Using a setting tool the engineer hand places leather onto the frame, while matching component for a perfect fit.
With its lightweight aluminum chassis and handmade construction, it takes two engineers bolt the transmission to the chassis. Making use of the BMW toy box, the MF5 GT borrows the BMW double wishbone suspension, performance coil springs and anti-roll bars. Wiesmann takes further use of its BMW toolbox, with a M5/M6 lifted V8 biturbo, producing 555bhp with the ability to sprint from 0-60 in 3.9 seconds. It takes 4 people to lift the rear body shell onto the back of the MF5 chassis. Another engineer attaches the driver and passenger doors on the hinges. Another technician installs the steering and wiring components, while three workers append the front body panel to the front of the chassis. The Wiesmann factory doesn’t use conveyor belts or robots; instead they employ 60 engineers who spend 350 hours on 1 car at a time, and makes 4 cars per week or 180 per year.