Things You'll Need
Foam manufacturer’s instructions
Hot glue gun
Light upholstery foam
Craft foam glue
Foam adhesive spray
Protective mask, goggles and gloves
Depending on its density, upholstery foam can be used in a variety of projects. Lighter, more porous upholstery foams are a good choice for home craft projects like kids' Halloween costumes. Stronger, denser upholstery foams are needed to make furniture. Your choice of foam glue depends on the type of project and the type of foam you're using. In general, craft glues are appropriate for lighter foams while a stronger epoxy glue is necessary for dense furniture foams.
Check the foam's packaging for any specific adhesives that the foam requires. Some foam will not stick together with certain types of glue, and some glue can damage certain types of foam. If the foam doesn't have manufacturer's instructions, test some small pieces with the glue you plan to use.
Use a hot glue gun on light upholstery foam for projects that don't need to be durable, such as wall hangings or costumes. Hot glue holds foam to foam, or you can use it to glue foam to other materials like wood and fabric.
Put the glue gun on the lowest setting because very hot glue will melt the foam. Hot glue sets quickly, so have ready the pieces you want to glue. Apply the glue evenly to both surfaces. If you're gluing fabric to foam, apply glue to the foam only. Press the two pieces together and let them sit for at least 30 minutes until the glue cools completely.
Use craft glue for foam on projects that need to be more durable. Available at craft stores, craft glue is similar to white paper glue, but it is runnier and stickier. It works on foam, wood, fabrics and plastics. spread the craft glue sparingly over both surfaces you want to stick together and let them sit for at least two minutes to allow the glue to get tacky, and then press them together for five to 10 minutes more. Do not use too much glue or it will soak into the foam and make it stiff.
Apply foam adhesive spray on dense foam used in upholstery projects. Be sure to use a protective mask and goggles on your face and gloves for your hands because this kind of glue is toxic. Spread newspaper under the pieces of foam you're gluing, and work in a well-ventilated place.
Spray both surfaces of the foam. Apply the glue evenly and press the foam together as quickly as possible. Spray foam adhesive becomes tacky within a few seconds, so it is ready to glue right away. If you're gluing fabric to foam, spray only the surface of the foam and smooth the fabric over the glue.
Press the foam together evenly for five minutes, until the glue sets. For large pieces, pinch the foam together along the glue seam. Hold each pinch for two seconds. Move back and forth along the seam with two-second pinches for five minutes until the foam bonds.
Always read the warnings on the package of glue you choose to use. Some glues are toxic and must be handled carefully.