Category Archives: Bonding

What you can do if you don’t want epoxy to stick

By Bruce Niederer — GBI Technical Advisor

We spend a good amount of time doing everything we can to inform our customers how best to make WEST SYSTEM® epoxy stick to wood, metal, and even plastic, or underwater with the introduction of  G/flex 650 and 655.  Still, there are many instances when you don’t want the epoxy to stick to one surface or another. This is where mold release agents come in very handy.

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Squeezing the Most Out of G/flex®

By Julie Jezowski

Are you the kind of person who just can’t get enough of a good thing? Looking for a better way to squeeze out that last little bit of G/flex 655 Thickened Epoxy Adhesive from your tube rather than resorting to pliers, a vise, or maybe even Grandma’s rolling pin? Maybe you’d like to get a fatter bead of adhesive or your tube is a bit clogged. Boy, do we have some easy and inexpensive tricks for you! 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

Flying Dutchman in need of repair

Flying Dutchman Repair

By Bill Bauer

On July 15th, 2006, a friend and I took my 1958 Flying Dutchman out for a sail in the Saginaw River. This was only the third time the boat had sailed in 30 years and the first hard sailing since my six-year-long restoration. We set both sails and made several runs in front of the Saginaw Bay Yacht Club before we hit something, maybe an old piling or maybe the freighter rudder that went missing the previous fall. 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

D-Ring Pads and G/flex Epoxy

by Tom Pawlak — GBI Technical Advisor

New Possibilities for HDPE Boats

D-ring pads are often attached to flexible surfaces with urethane adhesives to gain load-carrying capacity where there otherwise wouldn’t be any. They are used on waterproof fabric cargo bags, heavy tarpaulins, and inflatable boats. They are also sometimes used on the decks of canoes and kayaks to hold cargo in place on long trips. D-rings are not typically used on polyethylene canoes and kayaks because the urethane glues are not recommended for use on HDPE (high-density polyethylene) plastic. We experimented with gluing D-ring pads with G/flex 655 Thickened Epoxy Adhesive to HDPE plastic with that end-use in mind. Continue reading

Mixing G/Flex with Other WEST SYSTEM Epoxies

by Jeff Wright — Vice President of Technical Services

Above: Mixing G/flex with other WEST SYSTEM Epoxies increases the versatility of these epoxy systems.

WEST SYSTEM 105 Resin-based epoxy is a very versatile system. For years, experienced users have been mixing and blending the various product combinations in countless ways. For example, users may blend 205 Fast Hardener and 206 Slow Hardener to make a hardener with a modified cure speed. Different uses of 410 Microlight® Fairing Filler provide a further example. Many customers assume that the only use of 410 is to make a fairing compound—it is added to thicken epoxy to a peanut butter consistency to create a light, easily-sanded filler. Continue reading