Should I use carbon fiber prepreg or dry woven fabric, and which weight, weave and thickness?
Use dry woven fabric when you wet it out yourself with epoxy, polyester or vinyl ester resin[1]. Use prepreg when you want the resin already in the cloth at a fixed ratio, so every ply comes out the same. Zbrehon’s prepreg is carbon fiber in an epoxy matrix, made by the two-step film method, and is described as simple to handle and easy to store[2].
Which dry fabric weights are standard?
All standard fabrics are 1000 mm wide[3], in plain or twill weave.
- 1K: 100 g/m²[4][5]. The thinnest option, for very light skins.
- 3K: 200, 220 and 240 g/m²[6][7][8]. The usual choice for visible carbon surfaces.
- 12K: 400 and 480 g/m²[9][10]. Builds thickness faster in fewer plies.
Which prepreg grades are standard?
Every standard prepreg grade has a resin content of 42%[11]. The fiber weight sets the ply thickness:
| Fiber weight | Total prepreg weight | Thickness | Plain / twill code |
|---|---|---|---|
| 200 g/m² (3K) | 345 g/m² | 0.2 mm | P200R4224T / T200R4224T[12] |
| 220 g/m² (3K) | 380 g/m² | 0.28 mm | P220R4224T / T220R4224T[13] |
| 240 g/m² (3K) | 414 g/m² | 0.32 mm | P240R4224T / T240R4224T[14] |
| 280 g/m² (3K) | 482 g/m² | 0.34 mm | P280R4224T / T280R4224T[15] |
| 400 g/m² (12K) | 690 g/m² | 0.48 mm | P400R4224T / T400R4224T[16] |
To estimate a laminate, divide the target thickness by the ply thickness. For example, about 1 mm needs five plies of the 0.2 mm grade, or two plies of the 0.48 mm grade plus a thin face ply.
Plain or twill?
Both are listed at every weight. Plain weave holds its shape well on flat panels. Twill drapes more easily over curves and gives the diagonal pattern most buyers expect on visible carbon parts. If appearance matters, ask for a sample of each.
What to put in your inquiry
- Dry fabric or prepreg, and the model code.
- Your resin system and cure method if you buy dry fabric.
- Quantity in square meters, and whether you need samples first.
See the woven fabric and prepreg pages for the full tables, or send your list through the quote form.
Sources
- Carbon fiber woven fabric is woven from 1K, 3K, 6K, 12K or 24K carbon fiber, in plain, twill or satin weave. It is compatible with epoxy, polyester and vinyl…
- Carbon fiber prepreg is carbon fiber in an epoxy resin matrix, made by the two-step film method. It is an intermediate for producing composite parts, with…
- CY03P-200: Model: CY03P-200; Tow: 3K; Weave: Plain; Weight (g/m²): 200; Width (mm): 1000
- CP120: Model: CP120; Tow: 1K; Weave: Plain; Weight (g/m²): 100; Width (mm): 1000
- CT120: Model: CT120; Tow: 1K; Weave: Twill; Weight (g/m²): 100; Width (mm): 1000
- CY03T-200: Model: CY03T-200; Tow: 3K; Weave: Twill; Weight (g/m²): 200; Width (mm): 1000
- CY03T-220: Model: CY03T-220; Tow: 3K; Weave: Twill; Weight (g/m²): 220; Width (mm): 1000
- CY03T-240: Model: CY03T-240; Tow: 3K; Weave: Twill; Weight (g/m²): 240; Width (mm): 1000
- CY03P-400: Model: CY03P-400; Tow: 12K; Weave: Plain; Weight (g/m²): 400; Width (mm): 1000
- CY03P-480: Model: CY03P-480; Tow: 12K; Weave: Plain; Weight (g/m²): 480; Width (mm): 1000
- P200R4224T: Model: P200R4224T; Tow: 3K; Weave: Plain; Fiber weight (g/m²): 200; Resin content: 42%; Total weight (g/m²): 345; Thickness (mm): 0.2
- T200R4224T: Model: T200R4224T; Tow: 3K; Weave: Twill; Fiber weight (g/m²): 200; Resin content: 42%; Total weight (g/m²): 345; Thickness (mm): 0.2
- P220R4224T: Model: P220R4224T; Tow: 3K; Weave: Plain; Fiber weight (g/m²): 220; Resin content: 42%; Total weight (g/m²): 380; Thickness (mm): 0.28
- P240R4224T: Model: P240R4224T; Tow: 3K; Weave: Plain; Fiber weight (g/m²): 240; Resin content: 42%; Total weight (g/m²): 414; Thickness (mm): 0.32
- T280R4224T: Model: T280R4224T; Tow: 3K; Weave: Twill; Fiber weight (g/m²): 280; Resin content: 42%; Total weight (g/m²): 482; Thickness (mm): 0.34
- P400R4224T: Model: P400R4224T; Tow: 12K; Weave: Plain; Fiber weight (g/m²): 400; Resin content: 42%; Total weight (g/m²): 690; Thickness (mm): 0.48