Understanding Epoxy and Heat Deflection Temperature
Above: The test apparatus holds five of the test samples shown below in a bath of heated oil while a three-point load is applied to the sample. It is used to determine heat deflection under load (HDUL) temperature and the effects of high temperatures on cured epoxy.
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 epoxy application, we hope to dispel some of these misconceptions about epoxy and heat.
Tips for Sign Builders & Everyone Else
Above: Bonding fasteners in high-density urethane (HDU) foam calls for drilling an oversized hole slightly shallower than the fastener length and setting the fastener in an annulus of thickened epoxy.
Many of our readers who are familiar with WEST SYSTEM® Epoxy products for building and repair already know the benefits of fastener bonding techniques. WEST SYSTEM Epoxy has been used in other industries for many years as well, and these folks apply knowledge and techniques developed in the marine and aerospace industries in their work. A good example is the sign industry, a huge industry in the U.S. with companies ranging from mom & pop garage operations to multimillion-dollar corporations. Continue reading
Above: Our study of adding pigments to epoxy.
We often get asked ‘What can I use to color my epoxy?’ The intended application is as varied as our customers. Often it’s simply to make it easier to paint over or to provide a color indicator between layers. Sometimes it’s to match a particular colored material in a repair. Maybe it’s for an art or craft project. The point is, people are often looking for a color other than the black 423 Graphite, 501 White or 503 Gray Pigments offered in the WEST SYSTEM® product line. What are some options for adding pigments to epoxy? And what are the pigment’s effects on the performance of the epoxy? Continue reading
Above: We mixed and applied a third coat thickened with 406 Colloidal Silica Filler to create the texture for the non-skid finish on the deck.
This racing season onboard Triple Threat has been filled with the usual mix of tedium, laughs, and excitement. It’s a good thing when the exciting part is due to close racing and fast downwind surfing-it’s a bad thing if the excitement occurs when the foredeck crew nearly goes overboard because the deck is wet and the non-skid finish has the texture of a Slip n’ Slide! I’m happy to report no instances of skidding off the foredeck this year, as there had been in years past, because this year the non-skid finish was brand new. Continue reading
Above: Surprisingly, much of the damaged balsa core on TRIPLE THREAT was well bonded to the glass skin, as it was to this section of skin around the chainplate. The bad core that didn’t come out with the glass skin was removed with a chisel.
I love my boat. I love to spend time with it-sailing it, working on it, improving it.
I think I need my head examined. Continue reading
For a Community Sailing Program
Above: Optimist prams built by the SBCSA in the Gougeon boatshop, sailing before the Liberty Bridge on the Saginaw River.
Cover Photo: A new fleet of Optimist prams was built to serve the Saginaw Bay Community Sailing Association
The Saginaw Bay Community Sailing Association (SBCSA) was founded in 1995 by a group of local sailboat racers who shared a vision of a grassroots organization to provide area youngsters and adults a low-cost introduction to sailing. We began that first season with three Transfusion 547’s purchased for the association by Gougeon Brothers, Inc. (GBI) and a half dozen used Optimist prams donated by the Saginaw Bay Yacht Racing Association. Continue reading
Above: The layout of an Optimist pram provides an example of how to go about estimating epoxy amounts.
This formula will help you estimate the amount of mixed epoxy needed to wet out fiberglass cloth (assuming a resin-to-fiber ratio of 50:50) and apply three rolled epoxy coats to fill the weave of the cloth, i.e. “fill coats.” Continue reading
“…you’d see things my way!”
Are flexible epoxies better than stiff epoxies? How stiff is too stiff? How flexible is too flexible?
Read the title of this article again. Could a statement be more confrontational? I sure didn’t think so when my ex-wife laid it on me! The issue of “flexible” vs. “stiff” epoxies seems to have become a battleground in a continuing debate among adhesive manufacturers, wooden boat builders, restorers and repair yards. Who’s right and who’s wrong? Is it even a “right or wrong” argument? Continue reading
If your kids are like mine, they manage to break stuff you didn’t even think could be broken—constantly. As parents, we can either get inventive at repairing things we know little or nothing about, or we can get second jobs and pay someone else to fix everything. I like the first option better. Continue reading
The beauty of a wooden boat is undeniable. It doesn’t matter whether it’s sail or power. When I see one, my response is both cerebral and primal, and I know I’m not alone. I began racing sailboats in the late 1970’s and, without exception, it has always been aboard FRP production boats. In 1980, I was invited to crew on my first long distance race, hosted by the Buffalo Yacht Club near the northern end of Lake Erie. Continue reading