Fiberglass Reinforcement Guide: Mat, Cloth & 1708 Biaxial

Fiberglass Reinforcement Guide: Mat, Cloth & 1708 Biaxial

When it comes to fiberglass projects, choosing the right reinforcement is key to achieving the perfect balance of strength, finish, and ease of application. At True Composites, we offer multiple fiberglass materials, each with unique benefits. Let’s explore the differences between Chopped Strand Mat, Fiberglass Cloth, and 1708 Biaxial so you can select the best one for your next project.

1. Chopped Strand Mat (CSM)

Key Properties:

·     Made from randomly oriented fiberglass strands held together with a binder.

·     Builds thickness quickly and conforms easily to curves and corners.

·     Provides a smooth surface for gelcoat or paint.

Best Uses:

·     Ideal for molds, boat hull repairs, and creating a solid base layer.

·     Perfect for adding bulk between layers of other fabrics.

Recommendation:

If you need fast build-up and strong adhesion, our Fiberglass Chopped Strand Mat is your go-to choice.

***Compatible with polyester and vinyl ester resin. It is NOT compatible with epoxy resin.

2. Fiberglass Cloth

Key Properties:

·     Woven for uniform strength and smooth finishes.

·     Lightweight yet strong; moderate drape for shaped surfaces.

·     Provides a neat, professional appearance.

Best Uses:

·     Excellent for visible surfaces like surfboards, canoes, or automotive panels.

·     Perfect for small repairs and applications where appearance matters.

Recommendation:

Choose fiberglass cloth when smooth finish, strength-to-weight ratio, and appearance are your top priorities. See our Fiberglass Cloth options.

3. 1708 Biaxial

What It Is:

·     A stitched fabric combining biaxial cloth (fibers at ±45°) with a mat backing.

·     Offers the directional strength of cloth and the bonding/bulk benefits of mat — in one layer.

Key Properties:

·     Strong in multiple directions for structural integrity.

·     Builds thickness faster than cloth alone.

·     Excellent secondary bonding from the mat layer.

Best Uses:

·     Ideal for transoms, stringers, decks, and other high-strength repairs.

·     Reduces layup time by combining layers.

Recommendation:

For structural reinforcement with fewer layup steps, go with our1708 Biaxial Fiberglass Cloth.

Final Thoughts

While mat, cloth, and 1708 share the same fiberglass foundation, each serves a different purpose:

·     Mat → quick build-up & bonding

·     Cloth → smooth, lightweight finish

·     1708 → structural strength + bulk in one step

Choosing the right one will ensure your repair or build has the durability, finish, and performance you expect.