Why Are We Messing Around With Carbon Fiber?


Paul Crosby, the owner of Crosby Composites, leads the London-based company that’s been involved with motorsports for 20 years. They’re synonymous with elite quality – their work steeped in low volume, EXTREMELY high quality carbon fiber parts for Formula 1, the World Rally Championship and touring cars.

In fact, one of the coolest projects Paul’s team has been working on is the astounding RML-built Mercedes-Benz SLR Mclaren 722 GT. A 680Hp, completely reengineered version of the road-going SLR McLaren, Crosby Composites supplies all the new body components including: the wide wings, prominent side skirts, large rear diffuser and the huge hood. All obvious indicators of outstanding racetrack performance and extensive aerodynamic development.

Paul started the company after leaving the race world as an incredibly well-respected racecar engineer and has just recently returned to doing it in his spare time.

“When we got a call from Oakley asking about our capabilities to machine carbon fiber and heard what they wanted to do, we initially thought they were completely crazy. It turns out they are crazy, but we love it!”

Carbon is cut on 5-axis CNC vertical machining centers, otherwise known as milling machines. The end-mills are diamond-tipped and can cut insanely small.

How small? Try 0.5mm in diameter – about the size of lead in modern day mechanical pencils.

They spin fast – at up to 10,000 rpm during cutting. That’s roughly 3-to-5 times the rpm produced by a piston aircraft engine. Truly elite speed.

The end result is a unique “milled” aesthetic produced by cutting through the woven layers. It’s a funky effect, creating a topographical map of the layers themselves.

The extreme care that goes into choosing the cutter size, implementing the proper speed and the absence of coolant makes milling carbon fiber drastically different from milling metals. Simply stated: ensuring a smooth finish is a taxing, precise process.

Now, there are a lot of companies that could make great carbon fiber parts. Trouble is, most of them don’t have the cost-intensive machining equipment to actually do it.

Crosby Composites does. So why are we talking to the owner of a motorsports production company that specialized in elite parts?

Because we can.

What is carbon fiber?


Newbear Lesniewski


February 19, 2009

Related Photos