Custom framebuilding is often associated with steel and titanium, but every carbon frame, wheel, handlebar, or other part made with carbon-fiber sheet requires intensive hands-on work, whether the frame is a custom model from a small builder like Crumpton, or a production model from Giant or Trek.
The individual plies of carbon are often cut from a sheet by a computer-controlled machine, but that’s about the only automated process throughout production: A carbon-fiber composite frame or part must be assembled in a mold precisely according to the layup schedule, a process that has yet to be automated. In smaller facilities, one person may lay up an entire frame. In larger ones, workers will create a layup for a specific portion of a frame, like a bottom bracket area, then pass the part along to other workers to lay up around tubes, and place in the final mold for curing.
Even the post-cure process—where a frame is broken out of the mold, cleaned up, and painted—requires close attention. Expert workers examine the frame or part for problems like wrinkles in the carbon, or spots where the layers aren’t smoothly compacted, which could cause a failure.