Monthly Archives: March 2015

This joint style in an edge-glued, 1/8" thick HDPE strip holds tight when deflected and is great for gluing plastics.

Gluing Plastics with G/flex Epoxy

by Tom Pawlak — GBI Technical Advisor &  Jeff Wright — Vice President of Technical Services

Above: This joint style in an edge-glued, 1/8″ thick HDPE plastic strip which holds tight when deflected and is a good choice when gluing plastics.

One of our goals for G/flex® was the ability to bond to a variety of plastics. This was an ambitious goal because plastics historically have been used as mold release surfaces for epoxy, allowing the epoxy to release from the plastic when cured. While developing G/flex, we tested adhesion to a number of plastics with a variety of surface prep methods. Continue reading

Royalex Canoe Repair with G/flex Epoxy

By Bruce Newell and Stan Bradshaw

Above: Stan and Glenda Bradshaw in the Mad River Freedom 16′ Royalex canoe repaired with G/flex Epoxy in August 2007 on the Blackfoot River near Ovando, Montana a couple of miles downstream of the Roundup Bar.

The wooden gunwales of Royalex canoes can rip a hull apart if left out in bitter cold temperatures. Somewhere south of freezing, the plastic body of the canoe shrinks while the dampish wooden gunwales expand. Unless the screws affixing the inwale and outwale are backed out, they pin a shrinking hull to an expanding gunwale, and something will give. That something is always the hull. Continue reading

D-Ring Pads and G/flex Epoxy

by Tom Pawlak — GBI Technical Advisor

New Possibilities for HDPE Boats

D-ring pads are often attached to flexible surfaces with urethane adhesives to gain load-carrying capacity where there otherwise wouldn’t be any. They are used on waterproof fabric cargo bags, heavy tarpaulins, and inflatable boats. They are also sometimes used on the decks of canoes and kayaks to hold cargo in place on long trips. D-rings are not typically used on polyethylene canoes and kayaks because the urethane glues are not recommended for use on HDPE (high-density polyethylene) plastic. We experimented with gluing D-ring pads with G/flex 655 Thickened Epoxy Adhesive to HDPE plastic with that end-use in mind. Continue reading