Guides / Cost
How Carbon Fiber CNC Cutting Is Priced, Line by Line
Carbon Fiber Machining editorial team · October 19, 2026
Key points
- A quote for a routed carbon part is plate cost plus machine time plus setup plus finishing. Plate is often half the price.
- Sheet use matters: shops buy whole sheets and nest parts on them, and offcuts are rarely reusable.
- Machine time follows total cut length and thickness. Holes, countersinks and tight fits add time and inspection.
- Setup and programming are paid once, so the price per part drops quickly from about 10 pieces.
The price of a CNC-cut carbon fiber part comes from four things: the plate, the machine time, the setup and the finishing. On most small parts the plate is the biggest single cost, often around half of the quote. Machine time follows the total cut length and the thickness. Setup and programming are paid once per order, so they dominate on prototypes and fade on batches.
Knowing how a shop builds the number lets you read a quote, compare two of them and change the drawing where it saves money.
The plate: often half the price
Shops buy carbon plate in standard sheets and cut your parts from them. The price per sheet depends on:
- Fibre and resin system. Commercial 3K twill plate costs a fraction of aerospace prepreg plate with full certification.
- Thickness. Price rises roughly with the number of plies.
- Face finish. Gloss, matte and peel ply are similar. A guaranteed cosmetic grade with no visible flaws costs more.
- Construction. Woven, UD, quasi-isotropic and forged carbon all price differently.
Ask for the plate grade on the quote. Two quotes that differ a lot often differ in the plate, not in the machining.
Sheet use and nesting
A shop cannot sell you half a sheet unless it has another job for the other half. It nests your parts on a sheet to use as much of it as possible, and the waste is part of your price. Offcuts are rarely reused, because the next job needs a different thickness or finish.
| Order | Parts per sheet | Sheet use | Effect on price per part |
|---|---|---|---|
| 5 brackets, 120 x 80 mm | 5 on a part sheet | Low | Waste dominates |
| 200 brackets, 120 x 80 mm | About 20 per 500 x 500 mm sheet | High | Material cost per part drops |
| Odd shape with large voids | Poor nest | Medium | Ask if the shape can change |
Hypothetical figures to show the effect, not a quote.
Parts that nest tightly, with straight edges that can share a cut line or shapes that interlock, waste less plate.
Machine time: cut length, thickness and holes
Router time is roughly the total length of every outline, cutout and hole, divided by the feed rate, plus time for tool changes and moves. Feed drops as plate gets thicker, because the cutter must clear more material and stay sharp. Diamond-coated tools are expensive and the shop prices their wear into each job.
Holes add more than their cut length suggests. Each hole needs a drill or a helical interpolation, with backing on the exit side to prevent delamination, which we explain in drilling carbon fiber without delamination. Countersinks need a separate tool and depth control. Fits for bearings or dowels need a finishing pass and measurement.
Tolerances and inspection
Every tolerance tighter than the shop’s normal process adds time:
- ±0.1 mm on a routed profile is normal and costs nothing extra.
- ±0.05 mm needs better fixturing and a finishing pass on the features that carry it.
- Fits like H8 on a bearing seat need PCD tools and gauge checks.
- A thickness tolerance tighter than the plate maker’s means sorting or grinding sheets.
Call tight tolerances only where the part needs them. The design rules list the values that keep parts at normal cost.
Edge and surface finish
A routed edge is clean but sharp. Options that add handling time:
- Sanded edges, to remove sharpness and loose fibres.
- Chamfers, by a chamfer tool on the router or by hand.
- Sealed edges, with thin epoxy or lacquer, for parts that see moisture or fuel.
- Cosmetic face protection, film on the A side and extra care in handling and packing.
Say which you need. If the drawing is silent, shops quote as routed and lightly deburred.
Setup, programming and quantity
Before the first part, the shop imports your DXF, programs the tool paths, picks tools and sets up the hold-down. On a simple part this is a small block of time. On a part with pockets, countersinks and tight fits it is larger. Either way it is paid once per order.
| Quantity | Setup share of price | What changes |
|---|---|---|
| 1 to 5 | Most of the price | Prototype pricing |
| 10 to 50 | Falls quickly | Better nest, setup spread out |
| 100 and up | Small | Material and machine time dominate |
Typical pattern, not a quote. Actual numbers depend on the part.
Repeat orders also cost less to set up, because the program and fixture exist. Mention annual volume in the RFQ even if the first order is small.
Worked example (hypothetical)
A drone maker wants 400 arms per quarter: 4 mm 3K twill plate, 220 x 32 mm, six 3 mm holes, two slots, motor holes at ±0.05 mm, edges sanded, gloss side up.
A shop builds the quote like this:
- Plate: about 30 arms nest on one sheet. 400 arms need 14 sheets including setup waste.
- Machine time: outline, slots and holes per arm, at the feed for 4 mm plate. The motor holes get a finishing pass.
- Setup: programming, a vacuum fixture and the first-article check, spread over 400 parts.
- Finishing: edge sanding and protective film on the gloss face.
If the buyer changes the slot ends from square to round, relaxes non-motor holes to ±0.1 mm and orders 1,200 per year in three releases, the price per arm drops on every line except the plate.
Reading two quotes side by side
When two quotes differ, check in this order: plate grade and thickness, edge finish included or not, tolerances accepted as drawn or with exceptions, and packaging. Most gaps are explained there, not by the hourly rate. Our buyer’s guide to carbon fiber machining covers what else to check before you choose.
To get comparable quotes from shops that cut carbon every day, send your RFQ once and we match it with up to three of them. More on how flat parts are cut is on the sheet and plate cutting page, and our guide to preparing a DXF for carbon cutting shows how to avoid quote delays.
Frequently asked questions
Why is carbon fiber cutting more expensive than aluminium cutting?
The plate costs more per square metre, the tools are diamond-coated or PCD and still wear faster, and the shop needs dust extraction and more careful handling. Cutting speeds on a router can be similar, but the consumables and material push the price up.
Is it cheaper to supply my own carbon plate?
Sometimes. If you already buy plate in volume, sending it to the shop removes its material margin. You then carry the risk of scrap and the shop may ask for extra sheet to cover setup. For small orders it is usually simpler to let the shop buy the plate.
How can I lower the price of a carbon part?
Use a standard plate thickness and weave, relax tolerances that do not matter, use inside radii of 1.5 mm or more, keep holes at least the plate thickness in diameter and order in batches rather than one at a time.
Need a quote for a carbon part?
Send the DXF or STEP file. We match you with up to 3 shops that cut carbon fiber every day and reply within 24 business hours.
Get matched with a carbon shop