7-1/2 oz Fiberglass Fabric Overview

Commonly referred to as "boat cloth", this plain weave is an industry favorite for waterproofing and protecting various marine applications, like boats and personal watercraft. It offers nice handling and just one or two layers will get the job done quickly and easily.

Like other plain weaves, it delivers uniform strength in both horizontal and vertical directions, with warp and fill yarns at 0 and 90 degrees, respectively.

Features

• Popular fabric for boats and other marine recreational vehicles
• Uniform horizontal and vertical strength
• Cures transparent
• If requested, this fabric can be certified to meet the requirements of: AMS-3824 Style 2532; ASTM D 4029-09 Style 2532 and MIL-Y-1140

Tips

• Orient this fabric so that yarns run parallel to expected loads.
• During lay-up, add layers at alternating 45-degree angles to maximize strength.
• Use with epoxy resin, polyester resin, or vinyl ester resin to produce composite parts of excellent strength, low weight, and great cosmetics.

Specifications

Guarantee

Fibre Glast is committed to ensuring that every roll of fabric we handle is First Quality and manufactured to the highest standards, so that you can expect the same properties and handling characteristics every time you order.

Click here for more information on our First Quality Guarantee.

Why Choose 7-1/2 oz Fiberglass Fabric?

 
Medium-weight plain weaves, between six and ten ounces per square yard, are perhaps the most versatile fiberglass fabrics available. Typically called boat cloths, they are inexpensive, strong, and easily formed.

They retain enough flexibility to drape over most contours and they contribute significantly to the strength of the part. The 6, 7.5, and 10 oz fabrics are the most popular in the Fibre Glast fiberglass lineup, and the 7-1/2 oz is an industry favorite in this range. 

With a 50/50 fabric-to-resin ratio, the resin will weigh the same as the fabric. For a boat used near sandy shores, the 7.5 ounce fabric is an excellent choice, saving weight per layer compared to the 10 oz alternative.

If the shore is rocky, the 10 ounce fabric (#245/#271) might be a better choice for long-term durability despite the extra weight. Fiberglass is the all-purpose reinforcement choice in composites, and is perfect for everyday projects and parts. To maximize strength properties of fiberglass, it should be used with an epoxy resin. 

What Are the Best Applications for 7-1/2 oz Fiberglass Fabric?

The 7-1/2 oz fabric is also commonly combined with layers of mat when building molds, or used to protect the core in moldless construction. For marine use, no fewer than two layers should be considered. Woven Fiberglass Tape (#217 series) is matched to the #243 and #245 fabrics, so use tape at seams and edges where the wider fabric meets at joints.

How Should 7-1/2 oz Fiberglass Fabric Be Used for Best Results? 

Use squeegees, brushes, and rollers to saturate the reinforcement with resin and work air from the laminate. To increase the pliability of any fabric, cut it off the roll on a bias of 45 degrees. Even the coarsest fabric will drape better over contours when cut this way. 

38" Wide: #243 (cut-to-length min 10), #243-F (1 yd), #243-A (3 yd), #243-B (5 yd)

50" Wide: #244 (cut-to-length min 10), #244-F (1 yd), #244-A (3 yd), #244-B (5 yd)