Category Archives: Techniques & Tips

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

Protective skin creams-do they affect adhesion to the surfaces we touch?

By Tom Pawlak

We recently completed adhesion testing for a boatbuilder who was concerned about surfaces being contaminated by workers who use protective skin creams. The builder wanted to be sure that residue from the protective creams did not contaminate objects touched by workers throughout the day. We tested five products: Derma Shield™, Gloves in a Bottle™, Unique Skin™, SBS 46 Protective Cream™ and SBS 40 Medicated Skin Cream™. Continue reading

Scraper

Scrapers—Versatile Tools for Working with Epoxy

By Tom Pawlak

My first experience with cabinet scrapers occurred shortly after hiring into Gougeon Brothers. Bill Slaby, a wood/epoxy technician who specialized in mold building, routinely used cabinet scrapers to remove irregularities on cured epoxy coatings. I was intrigued with how quickly he could smooth up the epoxy with his scraper and particularly how he could get the epoxy to come off the surface in a continuous thin ribbon similar to wood shavings from a sharp wood plane. Bill was passionate about the benefits of scrapers and felt they were seriously underrated tools. He liked the absolute control you have in removing epoxy Continue reading

Estimating Epoxy Amounts

Estimating Epoxy Amounts

By Bruce Niederer

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.”

The formula includes a waste factor of approximately 15%; however, more (or less) may be needed depending on the job and personal application technique. The epoxy is applied at standard room temperature, approximately 72° F. Continue reading

The Scarffer is a tool for cutting plywood

Plywood Basics

By J.R. Watson

Since so many projects in Epoxyworks incorporate plywood, we felt it might be valuable to discuss briefly the types of plywood and some construction methods best suited to it. It’s easy to understand why people like plywood and choose it for so many projects: it is readily available, comes in convenient sheets (typically 4’×8′), is pretty light for its stiffness and strength (1/8″ plywood weighs about 11 lb per 32 sq ft panel), and is a bargain when compared to the price of many composite panels. However, plywood also has its weak points. There are limits regarding shape development because plywood can be compounded (bent in two directions at once) very little. In addition, plywood contains end grain on all its edges, Continue reading

Product Highlight: 804 Reusable Mixing Stick

Reusable Mixing Sticks are practical mixing, application, filleting and cleaning tools have found many places in our workshop toolboxes, and we believe they will in yours, too. The squared, beveled end reaches into the square corners of the 805 and 806 Mixing Pots for thorough mixing of epoxy and blending of fillers. Continue reading

Comparing Surface Preparation Techniques for Paints and Primers

By Joe Parker

Before you begin a project, it is a good idea to consider all of your options. Information about products or methods you may want to use is often available on product labels, from manufacturers, or your own experience. However, many times the information you need to make good choices is just not available. Then your best option is to test. In our most recent renovation, we had to figure out what to test for and how to do it. Continue reading

Bonding to Corian™ and Wilsonart™ Laminates

By Tom Pawlak

We recently did adhesion testing to Corian and Wilsonart surfaces with WEST SYSTEM 105 Resin and 206 Hardener at the request of a composite panel manufacturer. Corian and Wilsonart are mineral filled acrylic panels that look like granite and are often used as countertop material in kitchens and offices. Cabinetmakers and contractors typically use the panels in ½” thickness for residential applications. They are quite heavy, though not nearly as heavy as actual granite. Corian and Wilsonart are similar solid surfaces in that they can both be cut with conventional tools, then wet sanded and polished to a nice shine if they are damaged during installation. They are also available in thinner forms alone, or laminated over Continue reading

Research Chemist Bruce Niederer

“If You Were Just More Flexible”

“…you’d see things my way!”

Are flexible epoxies better than stiff epoxies? How stiff is too stiff? How flexible is too flexible?

By Bruce Niederer

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