Category Archives: Epoxy Products

WEST SYSTEM Launches G/Flex Epoxy

By Tom Pawlak

G/flex Epoxy is a toughened, resilient two-part epoxy engineered for a superior grip to metals, plastics, glass, masonry, fiberglass, and wet and difficult-to-bond woods. Introduced in June 2007, G/flex Epoxy is currently available in two consistencies: G/flex 650 Epoxy, a liquid epoxy, and G/flex 655 Epoxy Adhesive, a pre-thickened epoxy. Both have a 1:1 mix ratio.

G/flex Epoxy gives you 46 minute pot life and a long open or working time of 75 minutes at room temperature. It will reach an initial cure in 3–4 hours and a workable cure in 7–10 hours. Wait 24 hours before subjecting joints to high loads. Continue reading

Tools for Measuring Epoxy Quantities

320 Small Batch Epoxy Scale

WEST SYSTEM® recently introduced a new scale configured especially for measuring epoxy in very small amounts. The new 320 Small Batch Epoxy Scale accurately measures the correct ratio of resin and hardener for batches smaller than one 300 Mini Pump stroke. It allows for the accurate dispensing of epoxy resin and hardener in a range from 4.4 fl oz down to just a few drops of mixed product.
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Accelerated Testing: Hot Soak Moisture Uptake

By Bruce Niederer

We are constantly testing our products to fully understand and characterize them, and this is important both for ourselves and for our customers. A test method will usually produce results in a timely fashion, but there are times we must use an accelerated test method so we can get the results before we take that last lonely boat ride across the river Styx. This article describes some of the accelerated testing we do here.

WEST SYSTEM® epoxy is often used to provide a moisture barrier for applications that are in frequent or constant contact with water. In order to know how effective our epoxy is at resisting moisture, we have to be able to measure how much water it will Continue reading

Borate Salt Treats Decayed Wood

By Tom Pawlak

Sodium borate is used in a number of commonly used household products from laundry detergent to hand soap. It is also used to treat wood against insect and fungal attack. Sodium borate is refined from borax, a natural mineral, which is mined throughout the world. One of the largest deposits is in the Southwestern United States. (Think 20-Mule Team Borax™, Death Valley Days radio and TV shows).
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Comparing Cost and Weight of Flat Panels

By Jeff Wright

We compared the cost and weight of four panel types:

• Epoxy coated XL Plywood Boat Panel

• Epoxy coated Okoume Marine Plywood

• Epoxy/fiberglass/balsa cored composite

• Epoxy/fiberglass/core cell foam composite       

Many WEST SYSTEM® customers appreciate the benefits of cored composite construction. They understand that it creates a part that is lightweight, strong, and stiff. We often receive calls from these customers inquiring about using a composite panel when building or repairing something that would normally be made of plywood. Such projects may include a Continue reading

Effect of Surface Treatment on Adhesion to Metals

By Brian Knight

We have performed tens of thousands of adhesion tests over the years and many of these tests were done on metal surfaces. Below is a summary of tests done on a variety of metal surfaces and done with a variety of surface preparations. As you look at the chart, notice the surface preparation that gives the highest number.

All the tests shown below were performed using a PATTI (pneumatic adhesive tensile test instrument) meter. We chose this test method as our default adhesion Continue reading

WEST SYSTEM Epoxy vs. Polyester for Fiberglass Boat Repair

By Tom Pawlak

Even though we’ve been promoting the use of WEST SYSTEM® epoxy for repairing fiberglass boats (boats made with polyester resin) in our manuals and Epoxyworks for many years, we continue to receive inquiries asking whether it is appropriate to use epoxy for polyester boat repair. Because of the misinformation still prevalent in marinas, local yacht clubs and on the Internet, we felt it was time to restate the case for epoxy. Continue reading

Chopped Strand Mat

Chopped Strand Mat and Epoxy

By Tom Pawlak

Chopped strand mat, in fabric form, is sold on the roll and in small folded packages. It is made up of 1″-2″ long fiberglass strands that are randomly oriented and typically held together with a styrene-soluble binder that acts like glue connecting the fibers. The binder is designed to dissolve upon contact with styrene in polyester resin or vinylester resin. Once dissolved, the fabric softens, allowing it to drape around curved shapes. It comes in a variety Continue reading

G/5 Adhesive Tips

By Tom Pawlak

Many of us at Gougeon Brothers experiment with WEST SYSTEM® products on personal projects at home as well as at work. We often push products and techniques beyond the limits recommended in our literature. Sometimes the experiment fails, sometimes we discover something very useful. Continue reading

Testing large fasteners

Testing Large Bonded-In Fasteners

by Brian Knight

Epoxyworks 19

Cover Photo: The 154’7″ Bruce King-designed Scheherazade resting on her massive keel at Hodgdon Yachts in East Boothbay, Maine.

Scheherazade is a 154′ 7″ Bruce King designed ketch under construction at Hodgdon Yachts, in East Boothbay, Maine. Scheherazade is 60% larger than Antonisa, the last Bruce King/Hodgdon Yacht collaboration, and is the largest sailboat under construction in the United States. We first looked at Scheherazade in EPOXYWORKS 17, Spring 2001, before she was rolled and set on her 153,000 lb ballast keel. On a March, 2002 visit, Scheherazade was resting on her massive keel (cover), while far above, surrounded by multiple levels of staging, work continued on her interior and deck (below). Continue reading