Author Archives: ewadmin

Repairing cracks in concrete

Repairing Cracks in Concrete

by Brian Knight—GBI Technical Advisor

Cracks in poured concrete floors and foundation walls allow water to leak into basements and cause damage. With WEST SYSTEM® epoxy, you can, in many instances, fill the cracks from the inside and stop the water penetration without digging up your yard. WEST SYSTEM epoxy’s adhesion to concrete is excellent. It is very resistant to moisture penetration, and the tensile and compressive strength of the epoxy (about 8500 psi and 10,000 psi respectively) easily exceeds that of concrete. The following process is one method of epoxy injection that effectively seals cracks without requiring excavation outside the walls. The actual filling process takes some time, so use a slow hardener if the temperature is above 60°F. Continue reading →

Patching Cracks in Concrete Blocks

by Brian Knight—GBI Technical Advisor

Someone I know patched the cracks in the concrete block walls of her house using a different technique than the one I described in Repairing Cracks in Concrete. When it rained hard, her basement took on a lot of water through cracks in the walls. The cracks ranged in size from 1/16″ wide to some so large she could see daylight through them. Since concrete blocks are hollow, injecting WEST SYSTEM® Epoxy into the cracks would be unacceptable. So she decided to fill the cracks using epoxy thickened to a mortar-like consistency. Continue reading →

Decades of Epoxy Technology

By Tim Atkinson — Senior Chemist

Epoxyworks #4, Spring 1994

Cover Photo: The Formula 40 trimaran ADRENALIN is just one of the high-end epoxy composite structures built during Gougeon Brothers first 25 years.

Editors note: Our head chemist Tim Atkinson penned this piece on some of the history of Gougeon Brothers, Inc. on the occasion of our 25th anniversary, back in 1994.

In 1969, Meade Gougeon and his younger brother Jan founded Gougeon Brothers’ Boatworks to build iceboats. These lightweight, sail-powered vessels were built of wood laminated with epoxy. By 1973, the company was the largest builder of iceboats in the country. The company rapidly expanded its business into other boat-building efforts. Continue reading →

A Gadget for Easy Syringe Filling

by Brian Knight—GBI Technical Advisor

WEST SYSTEM® 807 Syringes are handy for injecting epoxy into hard-to-reach areas, but it’s difficult to load the syringe with thickened mixtures that won’t pour into the syringe body. With this gadget, loading non-sag mixtures is easy. It consists of a flat plastic disc with a short length of PVC pipe bonded over a hole cut in the center of the disc. Push the disc down in a container of thickened epoxy and epoxy is forced out through the hole in the disc, through the PVC tubing, and into the syringe. Continue reading →

Minimizing Amine Blush

By Tom Pawlak —GBI Technical Advisor & Tim Atkinson — Senior Chemist

I recently built a double-ended paddle for my kayak. The blades were made of thin mahogany plywood coated with epoxy. I had coated all the paddle parts with two coats of epoxy the day before, and overnight a thin oil-like film had formed on the surface of the epoxy. This is amine blush. To ensure a good bond between the blade and the shaft, I removed the blush with water, dulled the surface with an abrasive pad, and dried the surface with paper towels. I’m confident using my new kayak paddle because the mating surfaces of the shaft and blade were properly prepared prior to bonding. Continue reading →

Ticonderoga: Testing for the Toughest Deck Coverings

by William D. Bertelsen

Ticonderoga is a 220 ft. sidewheel steamboat built in 1906. She carried passengers on Lake Champlain until 1953. The Shelburne Museum wanted to replace the decks and cover them in a way that recreated the appearance and texture of the original canvas sheathing. But it was equally important that the authentic looking decks be durable enough to survive the unrelenting foot traffic inevitable for such a magnificent museum centerpiece. Continue reading →

Composites You Can Build

by Captain James R. Watson

Composites have been on the automobile motor sports racing scene for some time now. Indy cars, Formula 1, IMSA GTP (International Motor Sports Association Grand Touring Prototype), and others employ composites to the fullest limit of the imagination (and budget). Engine builders are even beginning to use composites for internal components. Autoweek, Advanced Composites and similar magazines write about composites constantly. But most of these applications involve sophisticated techniques, tooling and materials such as autoclaves and resin-impregnated materials (pre-pregs). These require aerospace-level technology not commonly available or economical for the amateur builder. Pre-pregs and other advanced composites employ adhesives that require an oven to promote curing (post cure). Continue reading →

Gelcoat Blister Repairs

by C. Joe Parker, Michael D. Arndt & Tim Atkinson — Senior Chemist 

In Epoxyworks #3 (Fall 1993), Robert Monroe discussed the idea that polyester is subject to degradation in much the same way as wood is affected by rot. Many cases of blistering are actually much more than a blister directly under the gelcoat. These blisters may be the first sign of laminate degradation. Once this degradation begins, it may be as difficult to stop and just as damaging as rot is in wood. Continue reading →

Big Shoe Repair

by The Restoration Clinic staff

The Restoration Clinic of Fort Lauderdale, Fla. completed major repairs on the Cartagena Shoes statue, a pair of seven foot by four foot shoes weighing one ton each. In Coral Gables’ Cartagena Plaza near the University of Miami, the shoes are a well-known fixture. They were smashed by a falling tree during Hurricane Andrew, and appeared to have been ruined. One shoe was broken into several large pieces, and the other was crushed. Continue reading →