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Campy Carbon crankset(6 posts)

Campy Carbon cranksetTom C
Sep 11, 2001 4:47 PM
If you go to the rumors page of Campy only via the Branford Bike website you can see pictures of the Carbon crank said to be 135 grams lighter than the all metal Record and in stores by November. Ya interested Doug?
re: Campy Carbon cranksetmackgoo
Sep 11, 2001 10:49 PM
I'll be lookin.
Typical Campy good looks...Cima
Sep 12, 2001 5:11 AM
But only time will tell how well they hold up. Personally, I'm more interested in how rigid the 180mm length of this crank will be compared to the alloy model.

Thanks for the information!!

CC
oops, missed your post - did anotherDog
Sep 12, 2001 5:22 AM
Yup, they look cool, and 135 grams off!
more info...alansutton
Sep 12, 2001 10:17 AM
High-end aluminum cranks are made entirely of forged aluminum and are finished considerably after the forging process. This finishing is typically done by hand where excess rough aluminum is ground away and the surfaced is polished and later anodized. The new Record composite arms are made of three materials, aluminum, carbon and the matrix. In the center of the Record arms is a forged aluminum core. A core is used because aluminum is a more suitable material for pedal threads, spindle and chainring holes. This core is left rough after forging for better for matrix bonding. Around this core is the carbon fibers which are made solid by a thermoplastic matrix. The matrix is the polymer "glue" which fills the voids between the fibers. There are two types of matrices, thermoset or thermoplastic. Thermoset hardens with heat, thermoplastic becomes plastic (softens, liquifies). Thermoplastic tends to be tougher but tend to have problems bonding to the aluminum. What's interesting is that Campy used a thermoplastic matrix as opposted to a thermoset matrix used by FSA. I doubt Campy was able to solve the bonding issues so I'll bet they found a clever way to "mechanically" join the core with the matrix.
Thermosets are hardened through chemical reaction, no?JS
Sep 12, 2001 12:35 PM
typically a "hardener" is added in much the same way fiberglass resin is hardened. This Chemical reaction produces heat which hardens the resin/matrix. The reason companies now use aluminum skeletons under the carbon is to control the critical BB spindle to pedal spindle distances and alignments. Fluctuations in this are what killed earlier efforts of all carbon cranksets.