Choosing glues can be confusing. If you are trying to sort what type of glue to use for a specific application, these here are some typical glues used in woodworking and around the home.
Epoxy (polyepoxide)
is a thermosetting polymer formed from the reaction of a resin with a hardener which must be mixed immediately before use. Epoxies are exceptional adhesives for wood, metal, glass, stone, and some plastics. They are better in heat and chemical resistance than other common adhesives and can be made flexible or rigid, transparent or opaque/colored, fast setting or slow setting. The best solvent for epoxy is acetone but you need to get it cleaned up before it cures. If epoxy gets on a surface that acetone will attack, try isopropyl alcohol.
You may think “Why not just use Super Glue?” Well, the price of epoxy is typically about one quarter of that Super Glue, so for large jobs epoxy may make more sense. Be sure to read the instructions and applications carefully when choosing an epoxy for your project.
Contact Cement
is a strong adhesive made of neoprene and synthetic rubber. Since it bonds almost instantly, it often eliminates the need to clamp the materials. Contact cement can be used with plastic, rubber, glass, leather, metal and veneer. On the negative side, contact cement can be susceptible to deterioration, and may not be as effective when a powerful bond is required for a long period of time.
Clean and dry all surfaces before applying contact cement – any dirt or residue may affect adhesion, reducing its effectiveness. Avoid skin contact by using a brush or roller to coat both surfaces before pressing them together. Stray cement can be removed with nail polish remover.
Spray Adhesive
is glue delivered in droplet form. It is strong-bonding, fast-drying glue that you just spray on. Great for paper, cardboard, fabric, cushion foam, plastic, metal, and wood. There is even a version that will bond material to Styrofoam.
When choosing a spray adhesive, note its tack (how quickly it bonds), and whether the bond is permanent, semi-permanent, or temporary. High tack means that the adhesive will grip nearly instantly, while low-tack adhesive can be easily repositioned. Permanent spray adhesive is perfect for applications like veneer. On the other hand, with a temporary adhesive spray you can tack a drawing directly to your project rather than having to trace it. Cut right through the paper and then peel off the drawing.
Model / Hobby Cement
forms a strong bond on acrylics and polystyrenes and can be used on most plastics. It is usually sold in tubes and dries clear and hard. Clamp the parts for about 10 minutes. Full curing time is about 24 hours. Excess glue may be removed with acetone or nail polish remover.
Spend some time looking at labels to be sure you are choosing the right glue for your project. And always be sure to keep adhesives out of reach of children.
