How Carbon Fibre Is Made: From Raw Material to Your Sunglasses
Carbon fibre is often described as a "wonder material," but how is it actually made? The process is fascinating — a complex transformation from a plastic-like precursor into one of the strongest materials on Earth. Here's the journey from raw material to the sunglasses on your face.
Step 1: The Precursor Fibre
Most carbon fibre starts as polyacrylonitrile (PAN), a type of acrylic material. PAN fibres are spun into thin strands — each one about 5-10 micrometres in diameter (a tenth the width of a human hair).
Step 2: Stabilisation
The PAN fibres are heated to 200-300°C in air for 30-120 minutes. This process, called oxidative stabilisation, rearranges the molecular structure of the fibres, converting them from a linear chain to a more thermally stable ladder structure. The fibres change from white to brown/black during this stage.
Step 3: Carbonisation
The stabilised fibres are heated to 1,000-3,000°C in an inert atmosphere (usually nitrogen). At these extreme temperatures, the non-carbon atoms (hydrogen, oxygen, nitrogen) are expelled, leaving behind a fibre that is 90-95% pure carbon. The atoms are arranged in crystal-like structures aligned along the fibre axis — this is what gives carbon fibre its extraordinary strength.
Step 4: Surface Treatment and Sizing
The raw carbon fibres undergo surface treatment (usually oxidation) to improve bonding with resin. A thin sizing (protective coating) is applied to prevent damage during handling and weaving.
Step 5: Weaving
Individual carbon fibres are bundled into tows (typically 3,000-12,000 fibres per tow) and woven into fabric. The weave pattern — plain, twill, or satin — affects both the appearance and the mechanical properties of the final product. The distinctive cross-hatch pattern you see on carbon fibre products is usually a 2x2 twill weave.
Step 6: Moulding and Curing
For sunglasses, the woven carbon fibre fabric is layered into precision moulds with a carefully calculated resin system. The layup — the number of layers and their orientations — determines the final properties of the frame. The mould is then heated under pressure to cure the resin, bonding everything into a solid composite.
Step 7: Finishing
Each frame is removed from the mould and goes through extensive finishing:
- Trimming excess material
- Sanding and smoothing edges
- Drilling and fitting hinge mechanisms
- Surface polishing or clear coating
- Quality inspection for structural integrity and dimensional accuracy
The Result
What emerges is a frame that's stronger than steel, lighter than aluminium, and resistant to corrosion, heat, and impact. The Voyager Black weighs just 22 grams — a testament to the remarkable properties that this complex manufacturing process achieves.
Understanding how it's made gives you a deeper appreciation for why it outperforms every other frame material. If you'd like to explore those properties in detail, our article on what makes carbon fibre the ultimate sunglasses material covers the strength, weight, and durability advantages head to head.
Every time you pick up a pair of carbon fibre sunglasses, you're holding the result of one of the most sophisticated material transformations in modern manufacturing. Explore the ShadyMate Voyager range to experience it yourself.
