Tag Archives: adhesion

Common Errors in Fiberglass Laminate Repair

By Jeff Wright — Vice President of Technical Services

While most of our customers are successful when using WEST SYSTEM Epoxy to repair a damaged fiberglass laminate, we have become familiar with some common errors that are easily preventable. These mistakes are made by both professionals and amateurs. The information discussed in this article is available in our Fiberglass Boat Repair Manual and WEST SYSTEM User Manual, and on the WEST SYSTEM website. Continue reading

Repairing a Keel with G/flex Epoxy

By Don Gutzmer – GBI Technical Advisor

The advantage of repairing a keel with G/flex Epoxy is that it is a toughened system that has a tensile elongation of more than 30 percent, which would prevent cracks from reappearing in the fairing compound. A local boat owner called our technical line and asked about repairing his cast-iron wing keel with WEST SYSTEM® Epoxy. He asked if a technical advisor would be willing to take a look at the cracks on his keel and recommend the best way to repair it. After looking at the boat I gave the customer a callback and recommended using G/flex® Epoxy. He asked if I knew of anyone in the area that could do the repair. I told him that I would be willing to take on the job and thought it would be a good opportunity to write an article about repairing a keel with G/flex Epoxy. Continue reading

adhesion testing equipment

Will It Stick?

Epoxy Adhesion Testing with NewWood and Granite

By Mike Barnard

Many times each day we get questions about epoxy sticking to various substrates. Most questions are about something that we have already tested, so we check our large database and advise on how best to adhere to the surface in question. Other times, the request is unique and we are unsure if WEST SYSTEM® Epoxy will stick to it or not. In the event we do not have any experience bonding to a material, we recommend testing the adhesion. Many times, this means gluing a wood block to the surface, then pulling the block off once the epoxy is cured.  The test method we use is much more quantitative than that because it measures how much force it takes to remove the epoxy. Continue reading

White oak samples for testing

Letters to the Editor – White Oak

By Bruce Niederer — GBI Technical Advisor

My article, White Oak Redux (Epoxyworks 34), generated two responses we wanted to share. We consider ourselves students as well as tech advisors and so we’re always open to learning something from others. Our readers are generally pretty savvy people, and when they take the time to write us a thoughtful letter, we feel compelled to share what we learn from them with the rest of our readers. Continue reading

Bond Lines in Adhesive Bonded Structures

Understanding Bond Line Stresses in Composites

By Jeff Wright — Vice President of Technical Services

This article will discuss some of the engineering aspects to consider when designing or repairing an adhesive bonded composite structure, particularly bond line stresses. Fiberglass reinforced plastic and other composites influence the design of many products manufactured today. Boat hulls, sports equipment and airplanes can easily take new, complex shapes when composites are used in place of traditional materials. Reinforcing structures also benefit from the versatility of composite materials when prefabricated components are bonded with a high-strength adhesive. Continue reading

White Oak Redux

White Oak Redux

by Bruce Niederer and Bill Bertelsen

Building stuff, especially boats, with wood is much like a religious calling; once you hear the call, there’s no turning back. Those who’ve heard the call will not suffer fools willingly, so when I decided to conduct some white oak adhesion and shear testing and report the results in Epoxyworks 31, skeptics and believers alike took to the internet wooden boat forums-and had no problem speaking their minds! Having healed from the pummeling I took in some quarters, I’m back again to report the promised follow-up test results. Continue reading

Shop Floor Testing Methods

Shop Floor Tests

By Jeff Wright — Vice President of Technical Services

Boatbuilders or advanced hobbyists often want to learn more about the characteristics of the fiberglass laminate they’ve just created. But sending samples to a professional testing laboratory can be expensive and impractical. Fortunately, you can do these simple shop floor test that will yield reasonably accurate results. Continue reading

So Stands the Mighty Oak

Testing Epoxy’s Adhesion to White Oak

By Bruce Niederer — GBI Technical Advisor

People have been building boats using white oak for centuries, sacrificing blood, sweat, and tears to engineer wonderful and enduring vessels of all shapes and sizes.

Oak was often used because of its desirable properties and behavior. It is dense, strong, rot-resistant, holds fasteners well, and can be steam bent. In the days before glues and adhesives, oak planking was used because it would swell considerably which resulted in tight and sound hulls, meaning little leaking and dry interiors. Of course, time marches inexorably forward, and eventually, builders began using adhesives to augment or, in some cases, replace mechanical fasteners.

We’ve been debating the issue of gluing oak ever since. Continue reading

Six10 Epoxy Adhesive

Understanding Six10 Epoxy Adhesive Properties

By Jeff Wright — Vice President of Technical Services

WEST SYSTEM® Six10 is a two-part, pre-thickened epoxy adhesive formulated with properties that make it perfect for many adhesive applications. Compared to other ready-to-dispense adhesives, its particular physical properties make it ideal for stitch and glue boat construction, fiberglass laminate repair and general bonding. This new formulation has a good balance between the elongation and toughness of G/flex® and the strength and stiffness of our 105 Resin-based epoxies. You can use it with as many materials as possible including wood, metals and composites. The long working time with fast thru-cure and unique shear thinning are additional characteristics formulated into Six10 that contribute to its ease of use. Continue reading

WEST SYSTEM Launches G/Flex Epoxy

by Tom Pawlak — GBI Technical Advisor

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. Continue reading