When you must bond Styrofoam to wood, you are actually bonding a plastic material to a wood material, as Styrofoam is a plastic product. Because Styrofoam is plastic, remember that using an adhesive that contains solvents may create toxic fumes. Styrofoam is also a nonporous material, which means that it will not absorb adhesive. Select a strong adhesive and give it ample time to set before you test the bond.
Apply a thin layer of glue to the wood where you wish to attach the Styrofoam. Spread the glue out into a thin coat with a paintbrush, if necessary.
Affix the Styrofoam piece onto the wood over the glue. Adjust the Styrofoam on the wood until you have it in the position you desire.
Attach the c-clamp over the Styrofoam and wood to hold the two items together securely. Use more than one c-clamp if the pieces are large. Space the clamps six to eight inches apart and tighten them enough to hold the Styrofoam in place without marring the surfaces of the Styrofoam or the wood.
Leave the c-clamps in place while the glue sets--at least two hours for best results. Remove the c-clamps after the glue dries completely.
Tug gently on the Styrofoam to ensure that the bond is secure.