Epoxies Have A Wide Acceptance In

Cooler temperatures slow the curing time and warmer temperatures will accelerate it.Most epoxies are formulated for use in moderate weather conditions, between 50 and 90 degrees Fahrenheit.The gap filling capability is no excuse for poor workmanship, but if a mistake is made, epoxy can be very forgiving. For safety and environmental reasons, spray the solvent into a container for proper disposal.Epoxy cures through an exothermic polymerization, or heat producing chemical reaction in which there is very little moisture loss, resulting in less than 0.Quick-sets are usually 1:1 by volume, so that equal amounts are squeezed from hypodermic-like syringes and mixed to a uniform color and consistency.00 per gallon, epoxies can be expensive, and because of limited shelf life, don't buy larger quantities than can be used in the recommended time frame.At as much as $50. Epoxy is a two part adhesive consisting of a resin and a hardener, and is primarily divided into two classes: quick-set and slow-set. This can be used to advantage by refrigerating the mixture to prolong pot life, or by warming the mixture to speed up the cure. Having been associated with the marine industry myself and with the use of epoxies for many years, I have developed a good working relationship with epoxies, and I use them quite often in place of other adhesives, especially when high strength and moisture resistance are factors.Epoxies have a wide acceptance in the marine industry, but they haven't caught on in the wood shop as well as they should. Some hardeners will harden from exposure to air, and water in either resin or hardener is a definite taboo.Probably the greatest advantage in using epoxy is the ability to join dissimilar materials. In an emergency repair, I have even used copper wool as reinforcement, along with the cabocil, allowing a boat owner to get to his home port before making the permanent repair.Care must be taken to avoid excessive heat and contamination of the product with water. The adhesion factor is as great on metal as it is on wood, but some non-porous materials need to be roughed up to enhance the bond.Storage instructions must be followed also.. The viscosity can be altered very easily by the addition of fillers such as sawdust, wood flour, talc, or colloidal silica. Too much or too little hardener can result in a gooey mess that never will cure. If using a spray gun, spray plenty of solvent through the gun to assure the complete flushing of the equipment.Slow-sets allow more open or working time, and can take up to 24 hours to cure. They can be anything from 1:1 to as much as 16:1, depending on curing time, viscosity, ultimate strength and intended use. As a matter of fact, too much clamping pressure can force the epoxy out of the joint resulting in a lean or starved joint. They don't take as much clamping pressure as other adhesives, and I have had success with only contact pressure.Depending on the use, application can be by roller, spray gun, trowel, or putty knife. The advantages are superior strength, water resistance and gap filling capability. They are further divided within these categories by the mixing ratios, which are designed by the manufacturer. Some are thin enough to be injected into joints with a hypodermic syringe. When using epoxy that is approaching the limits of it's shelf life, the resin and the hardener should be stirred thoroughly prior to mixing together. Stir the hardener to restore the consistency.Each manufacturer has his own specifications for mixing and using epoxy, and the instructions need to be followed.