Carbon Fiber Tow RFQ Checklist in one minute.
A complete carbon fiber tow RFQ states the tow size, fiber grade, sizing compatibility, downstream process, bobbin or spool requirement, trial and production quantity, destination and final application. Terms such as 12K, T700 or epoxy sizing describe different parts of the specification and should not be treated as interchangeable.
Technical review: 2026-07-22
What the terms mean.
Carbon fiber tow is a continuous bundle of carbon filaments supplied on a package for weaving, braiding, filament winding, pultrusion, prepreg conversion or chopping. The K value identifies approximate filament count; grade and sizing must be confirmed separately from tow size.
Key differences for material selection.
| RFQ field | Example | Why the supplier needs it |
|---|---|---|
| Tow size | 3K / 12K / 24K / 50K | Defines the approximate filament-count class and handling range |
| Fiber grade | T300 / T700 / project-defined | Controls the product family and applicable manufacturer data |
| Sizing | Epoxy-compatible / process-specific | Supports resin and downstream-process review |
| Package | Bobbin or spool format and target weight | Supports creel, handling, packing and quotation review |
| Process | Weaving / winding / pultrusion / prepreg | Connects the fiber package and sizing to the intended conversion route |
| Commercial scope | Trial and production quantity, destination | Supports availability, compliance and shipping review |
How engineers and buyers should choose.
Start with the downstream process and equipment rather than choosing tow size from K value alone.
Attach the required manufacturer grade or property document when a named grade is mandatory.
State the resin family and any sizing restriction; do not assume all epoxy-compatible sizings behave identically.
Confirm package dimensions, net package weight and creel limitations before the production quotation.
Separate the representative trial quantity from the expected production quantity.
Provide end use, end user and destination when compliance review is required.
Where this comparison matters.
Typical values to confirm.
| Specification | Typical options |
|---|---|
| Tow size | 1K / 3K / 6K / 12K / 24K / 48K / 50K by confirmed source |
| Grade | Order-specific; final values follow the selected manufacturer and batch documents |
| Sizing | Resin- and process-specific confirmation required |
| Package | Bobbin / spool / carton / pallet by confirmed order |
| Compliance | Destination and final application reviewed before supply where required |
Product pages to compare next.
Details needed before quotation.
Clear RFQ information helps avoid wrong material selection and repeated emails.
Common technical questions.
Is 12K T700 enough information for a carbon fiber tow quotation?
No. It identifies a tow-size class and grade family, but the exact manufacturer grade, sizing, package format, quantity, destination and downstream process still need confirmation.
Can one carbon fiber tow be used for weaving, pultrusion and filament winding?
A grade may be offered for more than one process, but sizing, package, spreading, fuzz control and equipment compatibility should be reviewed for the actual conversion route.
Should a buyer request a trial bobbin before production?
A representative trial is sensible when changing tow size, grade, sizing, source or equipment settings. Production approval remains based on the customer's process validation and selected batch documentation.
Does a larger K value mean stronger carbon fiber?
No. The K value is an approximate filament count. Strength and modulus are controlled by the selected fiber grade and manufacturer data, while final laminate performance also depends on processing and design.
Sources reviewed for this guide.
These references support the general process guidance. Final material approval must use the selected product, resin and process documentation.