Tag Archives: Tom Pawlak

Improved Mold Strongbacks

by Tom Pawlak — GBI Technical Advisor

Above: Three 8″ plywood supports isolate the mold from the mold strongback.

Back in the 1980s, Gougeon Brothers, Inc. was one of the largest producers of wind turbine blades in the US. The blades were built of wood veneer and epoxy, and varied in length from 10′ to 70′. They were built in halves and vacuum laminated in female molds built with WEST SYSTEM® Brand Epoxy. Tolerances were tight, and every aspect of the tooling was critical, from molding to assembly. If something wasn’t right when the two halves were glued together, there wasn’t much you could do to make it right later. Continue reading →

Repair Your Non-Skid Surface

With a flexible non-skid mold

by Tom Pawlak — GBI Technical Advisor

If the patterned non-skid on your production-built fiberglass boat needs repair, you may be interested to know that flexible molds are available for making professional-looking repairs. Continue reading →

WEST SYSTEM Epoxy vs. Polyester

for Fiberglass Boat Repair

by Tom Pawlak — GBI Technical Advisor

Above: Epoxy vs. polyester in a typical fiberglass boat repair cross-section.

Even though we’ve been promoting the use of WEST SYSTEM® Epoxy for repairing fiberglass boats (boats made with polyester resin) in our manuals and Epoxyworks for many years, we continue to receive inquiries asking whether it is appropriate to use epoxy for polyester boat repair. Because of the misinformation still prevalent in marinas, local yacht clubs and on the Internet, we felt it was time to restate the case for epoxy. Continue reading →

Epoxy’s Adhesion to Wood

Woods of the World Epoxy Adhesion Testing

by Tom Pawlak — GBI Technical Advisor

Above: Epoxy’s adhesion to wood is the focus of this study of dozens of wood varieties from Africa and the Philippines.

We recently purchased a 154-piece wood sampler from Eisenbrand Inc., Torrance, California. The 3″ × 6″ × ½” specimens originated from points all around the world. Each specimen was provided with its common name, scientific name, and country of origin. There were several specimens we’d never heard of in this study of epoxy’s adhesion to wood. Continue reading →

Chopped Strand Mat and Epoxy

by Tom Pawlak — GBI Technical Advisor

Above: Wet-out chopped strand mat and woven fabric test samples are prepared for moisture uptake testing.

Chopped strand mat, in fabric form, is sold on the roll and in small folded packages. It is made up of 1″-2″ long fiberglass strands that are randomly oriented and typically held together with a styrene-soluble binder that acts like glue connecting the fibers. The binder is designed to dissolve upon contact with styrene in polyester resin or vinylester resin. Once dissolved, the fabric softens, allowing it to drape around curved shapes. It comes in a variety of weights between .75 oz to 3 oz per square foot. The most popular weights are .75 oz and 1.5 oz. Continue reading →

Epoxy Adhesion Over Stains

by Tom Pawlak — GBI Technical Advisor

Above: Testing of epoxy adhesion over stains was done with a number of different stains.

We have occasionally reported results of adhesion testing of WEST SYSTEM® epoxy to wood coated with various stains. In “Varnish Over Epoxy,” we touched on the topic of wood stains under epoxy and warned that some oil-based stains would cause an adhesion problem for WEST SYSTEM Epoxy. Since then, we have done some additional adhesion testing of epoxy over a number of stains. Continue reading →

A Better Way to Prepare Fiberglass Laminates

by Tom Pawlak — GBI Technical Advisor

Above: The Rapid Strip Brush™ is a great tool when you want to prepare fiberglass laminates for epoxy adhesion.

During a recent inspirational hardware store visit, I discovered a rotary wire brush made by Norton™ called the Rapid Strip Brush™. It is used with an electric drill and produces results comparable to bead blasting or a needle scaler. The package says it can be used to abrade metal, masonry, and fiberglass. I immediately thought of a fiberglass application that I wanted to try it on. Continue reading →

Furniture Repair with G/5

A good method for particleboard furniture repair

by Tom Pawlak — GBI Technical Advisor

Above: Particleboard furniture repair can be tricky when screws strip out. G/5 Five Minute Epoxy Adhesive offers an easy solution to fixing inexpensive furniture when this happens.

I recently broke the leg off an old workshop table. The tabletop was made of particleboard covered with Formica®. The screws holding the leg in place had pulled out and taken chunks of particleboard with them. Continue reading →

Repairing a Cracked Plaster Ceiling

by Tom Pawlak — GBI Technical Advisor

Above: Tom’s approach to repairing cracked plaster involves Drilling into the lath and injecting thickened WEST SYSTEM Epoxy.

A 100-year-old friend called in tears because her living room ceiling had cracked and she was afraid that the plaster was going to fall. I did my best to calm her and offered to come over and take a quick look. Continue reading →

Testing DCPD Blend Laminates

By Tom Pawlak — GBI Technical Advisor

Above: A DCPD blend laminate repaired with WEST SYSTEM Epoxy is tested to failure. The laminate required gross deformation before it failed, meaning epoxy is an appropriate repair material for the type of laminates common on jet skis and snowmobiles.

Gougeon Brothers recently did R&D testing on DCPD blend laminates for a manufacturer who wanted to know if WEST SYSTEM® Epoxy could effectively repair them. DCPD blend laminates are injection-molded parts made with fiberglass and dicyclopentadiene (DCPD) blended polyester resin that included an internal mold release agent. The hoods and decks for many jet skis and snowmobiles are made with this material.

Continue reading →