Category Archives: Techniques & Tips

G/flex 650 and 655 Epoxies

Mixing G/Flex With Other West System Epoxies

By Jeff Wright — Vice President of Technical Services

WEST SYSTEM 105 Resin-based epoxy is a very versatile system. For years, experienced users have been blending the various products 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® 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. However, 410 Microlight can be used in other ways. Jon Staudacher in Epoxyworks 22 described how he applied a “runny” mixture of epoxy and 410 to fill the weave on a composite part and reduce the Continue reading

Moisture Exclusion Effectiveness (MEE)-comparison

Moisture Exclusion Effectiveness

By Bruce Niederer — GBI Technical Advisor

I get mad at my computer fairly often these days when it takes more than a few seconds to open a file from an obscure site on the other side of the planet. Who has that kind of time to waste? Don’t even ask about photo files. There’s no point in arguing about it—we live in an accelerated world. We hate waiting for anything. Putting the social implications of this aside, a business involved in technical applications and products cannot afford to wait for real time field test results. We need data and we need it yesterday!

The focus of this article on accelerated testing will be how we test the ability of a coating applied in a relatively thin film to resist water transmission. This test is called Moisture Exclusion Effectiveness (MEE). It is based on a method developed by the 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.

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

Understanding Flexible Properties

By Jeff Wright — Vice President of Technical Services

The Technical Staff at Gougeon Brothers, Inc. regularly discuss material properties in a variety of applications. For example, it is not uncommon for us to discuss with a customer how to use carbon fiber to stiffen a structure, such as the shaft of a kayak paddle, and then within minutes discuss with another how to bond a dimensionally unstable wood, such as oak, and ensure precautions are taken so that the relative movement of the wood will not cause a failure.

For the kayak paddle, the customer’s concern is that the epoxy will allow the stiff carbon fiber fabric to be as rigid as possible. For bonding the unstable wood, the Continue reading

Positive displacement epoxy pumps

Tools for Measuring Epoxy Quantities

303 and 305 High-Capacity Positive Displacement Pumps

 
305 Metering Pump

 

 

 

Updated Spring 2016

For measuring epoxy accurately, Gougeon Brothers, Inc. has introduced high-volume epoxy pumps that are extremely robust. These pumps dispense epoxy faster than any pump the company has previously offered.  The 303 and 305 Positive Displacement Pumps work by trapping a fixed amount of resin and hardener, then forcing (displacing) that trapped volume into the discharge pipe or system.  The mechanics of this setup mean that increases in resin viscosity due to temperature changes will not slow dispensing speeds. Positive latching lids help prevent contamination of resins and hardeners.

The new 303 Positive Displacement Pump is calibrated for WEST SYSTEM 3:1 ratio epoxies (105 Resin with 207 Special Clear Hardener or 209 Extra Slow Hardener) and is easily identified with a red base. The new 305 Positive Displacement Pump is calibrated for 5:1 ratio epoxies (105 Resin with 205 Fast Hardener or 206 Slow Hardener) and has a blue base.

Positive Displacement Pumps are also available with drum fittings.  These connect directly to WEST SYSTEM Resin and Hardener drums so there is no need to decant materials.  This setup conveniently streamlines the metering process for high-volume users, saving both time and money.

Accelerated Testing: Hot Soak Moisture Uptake

By Bruce Niederer — GBI Technical Advisor

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

Cleaning Tools

By Glenn House — Director of Product Safety and Regulatory Compliance

Cleaning tools used for applying epoxy often involves solvents that have strong odors and are flammable. A WEST SYSTEM® user suggested an alternative that does not have these problems: a solution of citrus-based hand cleaner and water. This solution will remove uncured epoxy from tools and can remove epoxy that has started to gel if the tools are allowed to soak for a few hours.
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Borate Salt Treats Decayed Wood

By Tom Pawlak — GBI Technical Advisor

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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Pot repair with epoxy

One-Shot Pot Repair

By Tom Pawlak — GBI Technical Advisor

My wife Mary and I recently went to the local building center to purchase a large planter pot for our patio. After we had agreed on a nice large terra-cotta beauty, I noticed another large pot that had a serious crack. I asked the associate for a price on it, knowing it would be easy to repair with WEST SYSTEM® epoxy. He said I would be doing him a favor if I took it away. So we came home with two pots for the price of one. Continue reading

If You Can’t Take the Heat…

By Bruce Niederer — GBI Technical Advisor

Among both professionals and amateurs in the world of composites, there are certain enduring misconceptions and rumors regarding the effects of elevated temperature on an epoxy bond. Armed with just enough misinformation to be dangerous, folks will make important decisions that can lead to costly or time-consuming mistakes that might have been avoided if they had an adequate understanding of the principles that encompass epoxy structures and temperature. By defining some commonly used terms and briefly discussing issues surrounding application, we hope to dispel some of these misconceptions. Continue reading