Having had carbon fiber bikes out in the market for over a decade now, you would imagine that the search for the perfect combination of carbon weave, tube shapes and wall thickness would have been reached by now. Surprisingly though, it is still just the beginning of a carbon era in the performance sports.
The objective of this research was to have a better understanding of carbon fiber and more specifically what to take into consideration when trying to use it for bicycle frame manufacturing.
In august of 2009, my partner and I completed two carbon fiber bike frames after months of research and manufacturing. The frames have been tested and ridden plenty to know that we were succesful. In the future we will be revisiting our techniques to optimize our designs.
The research consisted of
- Finding an appropriate resin and carbon fiber type
- Testing the resin and carbon fiber together to adquire useful material properties
- Building jigs and mandrels to lay up the carbon fiber
- Manufacturing metal inserts needed for merging bike frame with the rest of the hardware
- Manufacturing the bike frame
- The frame was built in the following method:
- Carbon fiber "socks" were layed on round pipes used as mandrels, treated heat shrink was used to compress the resin and fibers
- The carbon fiber tubes were pulled off using a hydraulic jack
- The tubes were then cut and coped to length
- In a jig that held all the pieces in place, the tube joints were wrapped with carbon fiber. We used a vaccuum bagging system for this portion
- Carved foam was then used to create fillets at the joints
