Choosing Adhesives, Glues & Epoxies

The best choice for home craft projects especially for young children. This glue is relatively inexpensive, and sets reasonable quickly. The glue will bond paper, fabric, cardboard, leather, cork and wood. It is ideal for children because it is not toxic nor is it flammable and it can be removed with soap and water from hands and other objects. It is packaged in plastic squeeze bottles of various sizes.

Note: Only inexperienced wood workers use white glue as an adhesive for wood. For wood working projects carpenter’s wood glue should be used.

Carpenters wood glue or woodworkers glue is often confused with white glue. Carpenters wood glue is the choice adhesive for most woodworking projects, especially furniture construction and repair when bonding is required. To distinguish it from white glue, carpenters wood glue is usually a pale yellow in color. It sets faster than white glue, has superior resistance to water and heat. Carpenters wood glue also sands much easier than white glue. It is not toxic nor is it flammable. In most cases the materials should be clamped while the glue cures.

Super glue is an instant setting adhesive that comes in a small tube. It has superior bonding strength and will bond most non-porous materials to themselves and others. Common applications and materials include bonding metals, ceramics, plastics, rubber, and synthetics. It has the disadvantage that it will bond skin together and hence must be used with caution. It is not a recommended adhesive for children. It should also be noted that its life, once the tube is opened is very limited.

Epoxy has a number of advantages as an adhesive. It is a very strong and permanent adhesive. It has the ability to fill voids. It is highly solvent and water resistant and can withstand impact including dropping bonded items. Most epoxies will set in about 5 minutes. The primary negative to epoxy is that it is a two part adhesive a resin and hardener. Some variation in the quality of the bond can occur if the resin and hardener are not mixed in the correct proportions. Many manufacturers have attempted to overcome this problem by creating dispensers that control the quantities being dispensed. Epoxy is both toxic and flammable prior to curing. Once cured, epoxy is no longer toxic. Common applications include the bonding of steel, wood, aluminum, stone, glass, brick, concrete and ceramics.

Polyurethane glue has a lot of the same qualities as epoxy without the disadvantage of requiring the mixing of a resin and hardener. It is recommended that materials be clamped during curing which occurs in approximately four hours (Note: Check the manufacturers cure time on the packaging as some polyurethane glues have cure times as long as 24 hours). Most polyurethane glues can be sanded, painted and stained although when used on wood the stain absorption will be different than the wood absorption. Polyurethane glues will bond wood, glass, ceramics, metal, stone and most rigid plastics. Polyurethane glue does expand when curing to fill voids. Wet polyurethane glue requires the use of acetone or mineral spirits for clean-up.

Additional information on when and how to use polyurethane glue.

Plastic glue also referred to as plastic cement’s primary application is plastic model toys. However, the product can be used to bond most items made from polystyrene or ABS plastics. Plastic glue is toxic and flammable. Plastic glue is designed to be put on one part only. Clamping the parts in place until the plastic glue cures is recommended. Plastic glue is generally sold in small tubes. Unused portions of glue, left in the tubes has a very limited life.

Contact cement does not adhere to anything but itself. The application of contact cement requires that both surfaces be coated with adhesive. The contact cement is left to dry and then the two surfaces are put together. Contact cements prime application is to bond laminates to wood such as in the manufacture of countertops. However, contact cement can also be used to bond foams, and metal to wood. The bonding is almost instantaneous which makes the use of the product difficult. Clamping is not required. However the use of a roller or other pressure on the surface of the bonded materials to eliminate air pockets is almost mandatory. Both flammable and non-flammable contact cements are available.

Resorcinol glue is similar to epoxy in the fact that it is a two part adhesive requiring the mixing of a resin and a hardener. The primary application for resorcinol glue is for exterior use where the bonding of wood materials must be water and weatherproof.

Silicone rubber adhesive is available in a squeeze tube or a cartridge that can be placed in a caulking gun. Silicone rubber adhesive is an excellent adhesive for exterior applications because it has very good bonding strength, is weatherproof and remains flexible in high and low temperatures. It is used as a bonding agent for automotive windshields. One of the biggest disadvantages of silicone rubber adhesive is that once the tube or cartridge is opened its usable life is very limited.

Plastic resin glue is the replacement for the hide glue used by furniture manufactures for many years. Plastic resin glue is manufactured as a powder and must be mixed with water to create an adhesive. Plastic resin glue primary application is in woodworking and a completed joint is stronger than the wood itself. The advantage of the product is that it will not stain the lumber and is very resistant to moisture. The plastic resin glue will not rot and is not susceptible to bacteria growth.

Construction adhesive takes its name because it is the primary choice when bonding of construction materials is required. The advantages of construction adhesive are that it bonds most materials used in construction to themselves and to each other. Common materials include molding, paneling, foam insulation, chair rails, cork, baseboards, plaster, ceramic and porcelain tile, natural stones such as marble and granite, masonry, and drywall. Construction adhesive is latex based so that it cleans up with water and as it is latex it is very low odor, making it an excellent adhesive for indoor construction applications. Construction adhesive does not require clamping and yet provides the ability to adjust the position of the materials to be bonded over a 15 minute period. It is sold in cartridges that fit standard caulking guns. Construction adhesive can be used on both horizontal and vertical surfaces.