Carbon Fiber sheet: properties, waterjet cutting, and design guide
Top 5 must-know things about Carbon Fiber
- Carbon fiber composite is a lightweight, high-strength laminate made of woven carbon fibers and epoxy resin.
- At SendCutSend, carbon fiber sheets are waterjet cut with ±0.009″ tolerance for clean, precise results.
- Available in six thicknesses from 0.040″ to 0.197″, shipped in just 2–4 business days.
- Stronger and stiffer than aluminum by weight, making it ideal for aerospace, automotive, drone, and performance applications.
- Cannot be bent or formed like metals—carbon fiber is best used flat or with engineered layups.
What is Carbon Fiber?
Carbon fiber composite sheet is created by laying woven carbon fibers in an epoxy resin matrix and curing them under heat and pressure. The result is a rigid laminate with exceptional stiffness, strength, and low weight, far outperforming metals on a weight-for-weight basis.
It’s used anywhere engineers need structural strength with minimal weight: from aerospace and automotive to sports equipment and robotics. At SendCutSend, carbon fiber is precision cut on industrial waterjets, making it easy to design and order custom parts in this high-performance material.
What are the key properties of Carbon Fiber?
Carbon fiber is known for its strength-to-weight ratio and dimensional stability. While aluminum is strong and ductile, carbon fiber is stiffer and lighter, but not designed to bend or stretch.
Typical properties of cured laminate include:
- Density:~0.06 lb/in³ (about half that of aluminum)
- Tensile strength: 500+ ksi (depending on fiber and layup)
- Modulus of elasticity: 20–30 Msi (very stiff)
- Thermal resistance:
Maintains properties up to ~250°F (121°C) continuous use
- Appearance: Black woven surface finish
These qualities make it ideal for lightweight, load-bearing panels, brackets, and housings.
Can Carbon Fiber be cut?
Yes, but not with traditional shop tools. Abrasive blades or saws can cut carbon fiber, but they often cause fraying, delamination, or excessive dust.
- Laser cutting is not recommended: the resin tends to burn and emit toxic fumes, and edges often char.
- CNC routing is possible, but requires careful feeds/speeds and creates hazardous dust.
- Waterjet cutting is the industry standard and the method used at SendCutSend. It avoids heat, eliminates burning, and delivers crisp, clean edges.
What edge quality issues occur when cutting Carbon Fiber?
Because carbon fiber is a layered composite, cutting methods can introduce defects if not done correctly:
- Delamination: Layers separating at the edges.
- Fiber pull-out:
- Resin burn or charring: From heat-based cutting like lasers.
With waterjet cutting, these issues are minimized. The abrasive jet slices through without heat, producing clean edges with minimal fraying. Parts arrive ready to use, though it’s best to handle edges carefully since they can be sharp.
What tolerances and minimum features are possible?
At SendCutSend, we hold ±0.009″ cutting tolerance on carbon fiber sheets.
- Minimum hole size: ~0.125″ for best results.
- Minimum web/bridge: At least 2x material thickness.
- Kerf width: Varies with abrasive stream, but generally ~0.030″.
For detailed specs, see the carbon fiber specifications section on our material page.
Can Carbon Fiber be bent or formed?
No—carbon fiber laminate cannot be bent or formed like sheet metal. Attempting to bend it will cause cracking or delamination. Complex 3D shapes must be molded during the layup process, not after curing.
For projects requiring bends, consider pairing carbon fiber flat panels with bent metal brackets (such as 5052 aluminum or 304 stainless steel) for hybrid assemblies.
What design rules help prevent cracking or delamination?
When designing for carbon fiber cutting:
- Avoid extremely thin webs—keep at least 2x thickness.
- Use rounded interior corners instead of sharp angles to reduce stress concentrations.
- Keep hole diameters ≥0.125″ to avoid fraying.
- Design parts to remain flat; do not expect bending or forming.
These practices ensure stronger, longer-lasting parts and reduce the risk of damage at cut edges.
Does Carbon Fiber degrade over time?
Carbon fiber itself does not rust or corrode, but it can degrade under certain conditions:
- UV exposure: Prolonged sunlight can yellow or weaken the resin. Protective coatings can help.
- Moisture:Epoxy resin is resistant but not completely waterproof; long-term immersion may affect performance.
- Fatigue:Repeated cyclic loads can cause cracks to propagate over time.
For indoor or occasional outdoor use, carbon fiber lasts many years. For permanent outdoor exposure, a UV-stable clear coat is recommended.
What are typical applications for Carbon Fiber?
Because of its strength and lightness, carbon fiber is common in:
- Drones and UAVs (frames, panels, brackets)
- Automotive and motorsports(interior panels, body parts, lightweight brackets)
- Aerospace (structural panels, housings)
- Robotics(arms, joints, lightweight components)
- Consumer products(sporting goods, electronics housings, performance gear)
If your project needs stiffness and weight savings, carbon fiber is often the best choice.
When should you cut Carbon Fiber yourself vs outsource?
DIY cutting of carbon fiber is possible with diamond-coated blades or carbide tools, but it comes with hazards:
- Creates fine carbon dust that requires PPE and dust collection.
- Edges may fray or delaminate without proper tooling.
- Small mistakes are costly due to material expense.
Outsourcing to SendCutSendensures:
- ±0.009″ precision with industrial waterjet cutting.
- No burning or fraying compared to laser cutting.
- Fast turnaround in 2–4 days.
For prototypes, performance parts, and production runs, outsourcing is almost always safer, faster, and more reliable.
How does SendCutSend cut Carbon Fiber?
We use abrasive waterjet cutting to process carbon fiber sheets. This method avoids the heat and burning issues of lasers while preserving the integrity of the composite.
- Clean edges with minimal delamination.
- ±0.009″ tolerance across all six available thicknesses.
- USA-sourced sheets for consistent quality.
Simply upload your design to our instant quoting system to get started.
Conclusion
Carbon fiber offers an unbeatable combination of low weight, high strength, and stiffness, making it ideal for drones, vehicles, aerospace, and robotics. While difficult to cut with DIY tools, SendCutSend makes it easy by providing precision waterjet cutting, fast turnaround, and consistent quality. If your design calls for strong, lightweight panels with a sleek black finish, carbon fiber is one of the best materials available.
