A foam rubber shoe has flexible and cushioned foam rubber for the sole or upper part of the shoe. Over time, the foam rubber can crack from frequent use and over-flexing of the shoe. If a piece of rubber rips off completely, you can repair it by gluing the piece back in place. You can also repair cracks in the surface of the rubber that come from frequent wear.
Wash the entire shoe with water and dish soap other mild soap. Use a soft brush or an old toothbrush and gently scrub the rubber areas. Rinse the shoe with clean water and a damp rag. Dry with old work towels. Allow the shoe to dry before doing any repairs.
Inspect the shoe for signs of damage. Look for cracks, loose rubber pieces and any areas where the rubber may have come off completely. If you have any rubber pieces that broke away from the shoe, find where they fit on the shoe.
Sand any areas of the shoe with loose or missing rubber pieces. Sand both sides of the rubber for the best fit. This roughs up the foam rubber, allowing the glue to bond better.
Repair missing pieces first. Apply a line of glue to the piece of rubber. Press the piece of rubber into the shoe's sole. Hold the piece against the shoe until the glue starts to dry.
Spread a line of glue between the loose flaps of rubber and the rest of the shoe. Press the two pieces together and hold in place for 60 seconds. If necessary, use a clamp to hold the two parts together while the glue dries.
Spread a line of glue inside any cracks in the foam rubber surface. Squeeze the two sides of the rubber together for two minutes. Wipe away any glue that seeps out from the crack with a damp rag.